Anthropology

Human Evolution

Timeline/Beginnings Brief Summary Summary/Conclusions

Comprehensive Summary With Links

Topics

• Darwin's theory of evolution was different from Lamarck's.
• Solving genetics problems using Punnett Squares.   
• Sickle-cell anemia/Tay-Sachs disease/Malaria/TB
• States where teaching evolutionary theory is under attack
• 5 Typical Characteristics Of Primates 
• To Be Or Not To Be A Chimp, That Is The Assignment And Question
• Evidence Which Shows That Australopithecus Africanus Was Bipedal
• Fossil Skeleton From Africa Predates Lucy
• Oldest creature on the human branch of the primate family tree Ardi predates Lucy.
• The Behavior Of Our Ape Relatives, Known As Peaceful Vegetarians
• The "Hobbits" Of Indonesia
• A skull that rewrites the history of man
• 5 things forensic anthropolgists try to determine from human remains/procedures

In Darwin's theory, natural selection plays the key role. Organisms vary through random mutations--slight changes from their parents. The environment determines which are most likely to survive.

In Lamarck's theory, changes in phenotype are inherited. This is now known to be (largely) incorrect.

Natural history series exploring the Galapagos Islands, which lie 1,000 kilometres off the coast of South America.

In the early 16th century, the first person in recorded history to set foot on Galapagos, the Bishop of Panama, deemed it a hellish place. He found no water and two of his men and ten of his horses perished.

Through time, this forbidding archipelago became the haunt of pirates and whalers, but as more people came to Galapagos, they began to see it in a whole new light.

In 1835, Charles Darwin's brush with these islands became the catalyst for a revolution that would transform our understanding of life on Earth.

From flightless cormorants hunting underwater to giant tortoises courting on the rim of an active volcano, a look at the hidden side of Galapagos, revealing why it is such a fascinating showcase for evolution.

1.  Three places Darwin visited during the voyage of H. M. S. Beagle

a. Most notably, the Galapagos Islands
         (Isabella, Santiago, Pinto, San Christobal, Florean)    

b. Valparaiso

c. Tahiti

2.  Five different kinds of animals that Darwin observed during the voyage

a. Giant tortoises

b. Conolophus – Land Iguana            Amblyrhynchus – Marine Iguana

c. Thirteen species of finches (‘Darwin’s finches’)

d. Sea Lions, Fur Seals

e. Penguins

3.  How Darwin's theory of evolution was different from Lamarck's.

   Lamarck posited that acquired characteristics could be inherited and species could evolve thereby.  Therefore, he reasoned that individuals who developed in their lifetimes characteristics helpful to survival could pass said characteristics to future generations. Darwin, on the other hand, was of the view that evolution of species occurred through change via the mechanism of natural selection and prospective reproductive success.

http://www.nzetc.org/tm/scholarly/tei-DarJour-_N66499.html

Postscript:

Professor Huld,

       I felt compelled to thank you again for the add; not to curry your favor but indeed to express profound thanks inasmuch as this is probably the last formal course at a formal educational institution I’ll ever take; and among the most important. While I had bought at discount a library-discarded 1993 Anthropology by Embers text, though meaning to read same never quite got to it. I am astounded by the substantial amount of time involved in the evolutionary process, not that I ever stopped to think about it, and one must come away with the sense of ‘and all that…..for this’. This course should be required curriculum along with psychology, sociology, etc., but probably won’t be owing to what is, as it should be, a very humbling educational experience for any member of the human race.

Regards,

             Al Peia

Solving genetics problems using Punnett Squares.   Check out  the Punnett Square website.

1.  Chinchillas are small, furry South American rodents.  They were originally brought to the United States from Chile in 1918 and raised for their fur, and have become increasingly popular as cage pets.  They come in a variety of colors, but the most common is gray.  In chinchillas, black fur is dominant to gray.  If one parent is gray, and the other is black heterozygous, what is the probability in their offspring of:

being homozygous dominant?      ____0____%

being heterozygous?                   ____50____%

being homozygous recessive?      ___50_____%

having black fur?                        ____50____%

2. Bambi, a rock music groupie, just had a child.  She isn't sure who the father is.  Bambi is blood type A and the baby is type O.  Use your knowledge of genetics to help Bambi, and indicate whether each of the following men COULD be the father.  If he could be the father, put down Yes.  If not, just say No, which is perhaps what Bambi should have done.

Jim, the vocalist and front man (type A homozygous)   __no____

Ray, keyboardist (type B heterozygous)                      ___yes___

Robby, the guitarist (type O)                                     ___yes___

John, the drummer (type AB)                                    ___no___

3. If both parents are blood type AB, which blood type(s) CANNOT occur in their children? Type O

I. The sickle-cell anemia website.

http://www.ygyh.org/sickle/whatisit.htm

1. About how many people die of sickle-cell anemia each year? Approximately 100,000 per year

USA for Sickle Cell Anemia: 500 per year, 41 per month, 9 per week, 1 per day, 0 per hour, 0 per minute, 0 per second.

2. List three places outside of Africa where sickle-cell anemia is fairly common

a. Mediterranean

b. Middle East / Arabia

c. South Asia, Southwest Asia, India

(also Latin America and the Caribbean )

3. About how many people are infected with malaria every year, and what does this have to do with sickle-cell anemia?

Each year more than 200 million people develop malaria. More than one million people die from malaria each year.

Sickle-cell anemia grants resistance from malaria. malaria infects the red blood cells, and sickle cells provide some immunity from this.

‘The presence of the parasite reduces oxygen tension in the cell -- when oxygen is reduced the cell will sickle. Because sickle cells are removed from the circulation, selective sickling of infected sickle trait red cells would reduce the parasite burden in people with sickle trait. These people would be more likely to survive acute malarial infections.’ http://www.answerbag.com/q_view/487972

II. The Tay-Sachs disease website

http://www.ygyh.org/tay/whatisit.htm

1. The three types of Tay-Sachs disease are:

a. Infantile/early onset

b. Juvenile

c. Adult/late onset

2. Tay-Sachs disease is fairly common among Ashkenazic (East European) Jews and:

 French Canadians, Louisiana Cajuns, and American Jews

3. Tay-Sachs disease might be an adaptation to TB (prevalence in urban environments).

The following is for my prospective reference:

http://www.mayoclinic.org/tay-sachs-disease/symptoms.html There are three forms of Tay-Sachs disease, categorized by the types of symptoms and the age when the symptoms first appear. The most common form appears when the child is 3 to 6 months old, with the disease progressing rapidly to death by age 4 or 5. At birth, the infant appears healthy and develops normally for the first few months of life, but as the buildup of ganglioside GM2 begins to affect nerves, symptoms appear.

Initially, symptoms may include:

• Seizures
• Noticeable behavior changes, such as the infant stops smiling, crawling or rolling over and loses the ability to grasp or reach out
• Increased startle reaction
• Decreased eye contact
• Listlessness
• Increasing irritability
• Slow body growth with increasing head size
• Delayed mental and social skills

As the disease progresses, these symptoms become more dominant:

• Feeding difficulties
• Abnormal body tone
• Loss of motor skills
• Blindness
• Deafness
• Loss of intellectual skills

Much rarer are the forms of Tay-Sachs that develop later in life and are due to low levels of the hex A enzyme, rather than the complete deficiency of hex A in the infantile form. Children with juvenile hex A deficiency develop symptoms between ages 2 and 5, and usually die by age 15. A milder form of hex A deficiency can develop anywhere from age 5 to the early 30s. Symptoms include slurred speech, an unsteady gait, tremors and, sometimes, mental illness.

Malaria is not caused by a mosquito but by a parasite in the mosquito. The malaria parasite needs the mosquito to reproduce and spread. The gametocyte is the developmental stage of the parasite that can be transmitted from people to the mosquito. In the mosquito's stomach the gametes are released and fertilisation takes place. The parasite develops further until the final stage (the sporozoite) in the salivary gland. The sporozoite can be transmitted with the saliva to a person if he/she is bitten by this mosquito. There the parasite reproduces rapidly and the person becomes ill.

1.  The National Center for Science Education lists 5 states where the teaching of evolutionary theory is under attack

a. Florida

b. Kansas

c. Tennessee

d. Arkansas

e. Louisiana WY, ME, OH, OK, NH, FL, AL, ND, GA, MS, TN, WV, KY

2. Edward Humes' "Monkey Girl" website list common misconceptions about evolutionary theory.  MONKEY GIRL: Evolution Facts and Myths

• Myth: Evolutionary theory holds that life on Earth, including humans, arose by luck or random chance.
• Fact: Evolution is mindless, but never random. Variations (in height, strength, intelligence, disease resistance, etc.) occur naturally among members of every species, from jalapeños to humans. Variations that help individuals survive (and reproduce) become concentrated in later generations, gradually transforming a species. Variations that pose a disadvantage are weeded out of the gene pool through the death of individuals or the extinction of whole species. This “natural selection” is evolution’s main engine.
• Myth: Evolutionary theory states that man evolved from monkeys.
• Fact: Evolutionary theory states that man and monkeys share a common ancestor that was neither man nor monkey, but possessed qualities passed on to each. Every species on Earth has an ancestor in common with every other species – some dating back millions of years, some hundreds of millions, others dating back billions of years. One implication of common ancestry is that there are far more extinct species than living ones; evidence in the fossil record and in living DNA suggests that more than 99 percent of creatures that have lived on Earth are now extinct.
• Myth: Belief in evolution requires atheism or leads to it.
• Fact: Most scientists accept the validity of evolutionary theory AND believe in God. Charles Darwin was trained to be a preacher and wrote that evolution and belief in God were completely compatible (with evolution contradicting only biblical literalism). It is true that Darwin grew to doubt the existence of God, but not because of evolution. He lost his faith when his young daughter, Annie, died.
• Myth: Evolutionary theory asserts that life arose from nonliving chemicals in Earth’s primordial environment — a process called abiogenesis, popularly referred to as “from goo to you.”
• Fact: Evolutionary theory has nothing to do with the beginning of life. It explains how life forms change over time, and does not attempt to explain how life began in the first place. Thus, evolutionary theory has nothing to do with creation but only change.
• Myth: There is more factual evidence to support the biblical account of creation than evolution.
• Fact: There is more scientific evidence, laboratory testing and direct observation to support evolutionary theory than virtually any other scientific theory, including gravitational theory* and the big bang theory. No credible evidence has yet falsified the theory of evolution, while new discoveries Darwin never dreamt of, such as the unraveling of the human genome, have supported his theory. On the other hand, there is no evidence outside of the Bible itself to support the Genesis creation and flood stories, and considerable evidence of inaccuracies and contradictions in Genesis’s description of the physical universe (such as a flat and motionless earth at the center of the universe). This is why many theologians, as well as the doctrines of mainstream churches and synagogues, avoid literal readings of Genesis in favor of metaphorical interpretations.
• Myth: Intelligent Design is a scientific theory that has detected scientific evidence of God. It is a legitimate scientific rival for the theory of evolution.
• Fact: Intelligent Design is a non-biblical form of creationism that avoids overtly religious references but posits an unnamed master “designer” by claming certain features in biology — particularly DNA and the complex molecular “machines” inside living cells — appear to have been designed, in the same way humans design software and complex devices. Because it posits a supernatural process — an intelligent designer fashioning life and the universe — it falls outside what is conventionally considered the realm of science, which is generally defined as the search for natural explanations for natural phenomena. This is why evolution is a scientific idea, while Intelligent Design is seen by many as a religious idea.
• Myth: the modern Intelligent Design movement was conceived by scientists to further human knowledge and understanding.
• Fact: The modern Intelligent Design movement was conceived by a lawyer in order to overthrow evolutionary theory and bring God “back” to public school classrooms.
• Myth: The teaching of evolution in public schools has undermined belief in God.
• Fact: Only one fifth of Americans believe humans evolved from earlier species.
• Fact: Sixty-four percent of Americans are creationists (meaning they believe humans were created directly by God, as in the biblical Genesis).
• Fact: About half of Americans believe God created the Earth and all life less than ten thousand years ago.
• Fact: A majority of Americans — including President Bush — believes evolution, intelligent design, and creationism should all be taught in public schools equally.
• Fact: The more educated a person is, the more likely that person will accept the validity of evolution and reject creationism (65 percent of Americans who attended graduate school believe evolutionary theory is scientific and well-supported by the evidence; 52 percent of those with bachelor’ degrees accept evolution; 20 percent of Americans with high school educations or less believe evolutionary theory is well supported by the facts).
• Fact: 98 percent of scientists in the nation and world accept scientific evidence that the earth is four billion years old and that primitive life first appeared on the planet three billion years ago.
• Fact: A majority of Americans who reject evolutionary theory as invalid have no clear or accurate understanding of what it is they are rejecting.

*There is, of course, no doubt that gravity exists, but the understanding of how and why it effects space and time is surprisingly incomplete when it comes to laboratory evidence. For instance, the existence of gravitational waves is predicted by gravitational theory, but despite determined efforts by physicists for many years, such waves have never been directly detected. Evolution, on the other hand, has been observed directly in the laboratory and in nature innumerable times.

5 TYPICAL CHARACTERISTICS OF PRIMATES 

a. Most primates see in color, all in 3 dimensions, and have depth perception (stereoscopic vision)-their eyes facing forward.

b. They are prehensile; that is, they have the ability to grasp objects with their hands (and in some instances with their feet).

c. Most primate species give birth to one offspring at a time.

d. A relatively bigger, more complex brain, particularly the neocortex enabling more complex thought processes.

e. They are social animals.

THE PRIMATE GALLERY WEBSITE, AND EXAMPLES OF:

1. a prosimian – Crowned Lemur of Madagascar

2. a New World monkey - The Andrean titi monkey (Callicebus oenanthe)

3. an Old World monkey - Rhesus monkey

4. an ape - Western Lowland Gorilla

5. a hominin - So, roughly speaking, a Hominin is what we used to call a Hominid; a creature that paleoanthropologists have agreed is human or a human ancestor. These include all of the Homo species (Homo sapiens, H. ergaster, H. rudolfensis), all of the Australopithecines (Australopithicus africanus, A. boisei, etc.) and other ancient forms like Paranthropus and Ardipithecus. http://archaeology.about.com/od/hterms/g/hominin.htm

To Be or Not To Be a Chimp, that is the Assignment and Question

http://moodle.lattc.edu/mod/resource/view.php?r=47978

5 similarities to chimp life

1. I get up in the morning and get something to eat.
2. I find hunting for food better alone.
3. I would consider a rest/nap to maximize performance and rejuvenate.
4. I like eating fruit and particularly like to eat meat.
5. After the expenditure of energy I ultimately rest.

5 differences from chimp life

1. I like cats.
2. I’m predominately a meat-eater who prefers the meat of larger animals; ie.; cows, etc..
3. I think the so-called dominance hierarchy a sham, a fraud, and comprised predominantly by incompetent fools and frauds.
4. I make time to learn new things because I’m much smarter than chiumps.
5. I exercise formally in addition to that derived from normal activities.

EVIDENCE WHICH SHOWS THAT AUSTRALOPITHECUS AFRICANUS WAS BIPEDAL

1) The position of the foramen magnum(*) convinced Dart that this was a bipedal human ancestor, which he named Australopithecus africanus (African southern ape).

2) The pelvis is more human than apelike, and is strong evidence that africanus was bipedal (Brace et al. 1979), although it may not have had the strong striding gait of modern humans (Burenhult 1993).

3) An abundance of the younger species A. afarensis (4 to 2.8 Ma) and A. africanus (3 to 2 Ma) fossils also show clear signs of habitual bipedalism, including a bicondylar angle, an anteriorly placed foramen magnum, laterally flaring iliac blades, longer femoral necks and heads, and the presence of a lumbar curve. Though A. afarensis seems to have originated in Ethiopia and A. africanus is found only in South Africa, both of these species lived in open habitats, possibly wooded savanna areas near a lake

EVIDENCE WHICH SHOWS THAT AUSTRALOPITHECUS AFRICANUS WAS BIPEDAL

Taung 1, "Taung Child", Australopithecus africanus
Discovered by Raymond Dart in 1924 at Taung in South Africa (Dart 1925). The find consisted of a full face, teeth and jaws, and an endocranial cast of the brain. It is between 2 and 3 million years old, but it and most other South African fossils are found in cave deposits that are difficult to date. The teeth of this skull showed it to be from an infant about 5 or 6 years old (it is now believed that australopithecines matured faster than humans, and that the Taung child was about 3). The brain size was 410 cc, and would have been around 440 cc as an adult. The large rounded brain, canine teeth which were small and not apelike, and the position of the foramen magnum(*) convinced Dart that this was a bipedal human ancestor, which he named Australopithecus africanus (African southern ape). Although the discovery became famous, Dart's interpretation was rejected by the scientific community until the mid-1940's, following the discovery of other similar fossils.

(*) Anatomical digression: the foramen magnum is the hole in the skull through which the spinal cord passes. In apes, it is towards the back of the skull, because of their quadrupedal posture. In humans it is at the bottom of the skull because our head is balanced on top of a vertical column. In australopithecines it is also placed forward from the ape position, although not always as far forward as in humans.

TM 1512, Australopithecus africanus (was Plesianthropus transvaalensis)
Discovered by Robert Broom in 1936 at Sterkfontein in South Africa (Broom 1936). The second australopithecine fossil found, it consisted of parts of the face, upper jaw and braincase.

Sts 5, "Mrs Ples", Australopithecus africanus
Discovered by Robert Broom in 1947 at Sterkfontein in South Africa. It is a very well preserved cranium of an adult. It has usually been thought to be female, but there has been a recent claim that it is male. It is the best specimen of africanus. It is about 2.5 million years old, with a brain size of about 485 cc. (It has recently been claimed that the fossils Sts 5 and Sts 14 (see next entry) were from the same individual)

Sts 14, Australopithecus africanus
Discovered by Robert Broom and J.T. Robinson in 1947 at Sterkfontein (Broom and Robinson 1947). Estimated age is about 2.5 million years. This find consisted of a nearly complete vertebral column, pelvis, some rib fragments, and part of a femur of a very small adult. The pelvis is more human than apelike, and is strong evidence that africanus was bipedal (Brace et al. 1979), although it may not have had the strong striding gait of modern humans (Burenhult 1993).

Additionally:

An abundance of the younger species A. afarensis (4 to 2.8 Ma) and A. africanus (3 to 2 Ma) fossils also show clear signs of habitual bipedalism, including a bicondylar angle, an anteriorly placed foramen magnum, laterally flaring iliac blades, longer femoral necks and heads, and the presence of a lumbar curve. Though A. afarensis seems to have originated in Ethiopia and A. africanus is found only in South Africa, both of these species lived in open habitats, possibly wooded savanna areas near a lake^8-10.

The following is for my prospective reference:

Prominent Hominid Fossils

Sahelanthropus tchadensis Ardipithecus ramidus Australopithecus anamensis Australopithecus afarensis Kenyanthropus platyops Australopithecus africanus Australopithecus garhi Australopithecus aethiopicus Australopithecus robustus

Australopithecus boisei Homo habilis Homo georgicus Homo erectus Homo ergaster Homo antecessor Homo heidelbergensis Homo neanderthalensis Homo floresiensis Homo sapiens

This list includes fossils that are important for either their scientific or historic interest, or because they are often mentioned by creationists. One sometimes reads that all hominid fossils could fit in a coffin, or on a table, or a billiard table. That is a misleading image, as there are now thousands of hominid fossils. They are however mostly fragmentary, often consisting of single bones or isolated teeth. Complete skulls and skeletons are rare.

The list is sorted by species, going from older to more recent species. Within each species, finds are sorted by the order of their discovery. Each species has a type specimen which was used to define it.

Each entry will consist of a specimen number if known (or the site name, if many fossils were found in one place), any nicknames in quotes, and a species name. The species name will be followed by a '?' if suspect. If the fossil was originally placed in a different species, that name will also be given.

The following terminology is used. A skull refers to all the bones of the head. A cranium is a skull minus the lower jaw. A braincase is the cranium minus the face and upper jaw. A skullcap is the top portion of the braincase.

Abbreviations: ER East (Lake) Rudolf, Kenya
 WT West (Lake) Turkana, Kenya
 KP Kanapoi, Kenya
 SK Swartkrans, South Africa
 Sts,Stw Sterkfontein, South Africa
 TM Transvaal Museum, South Africa
 OH Olduvai Hominid, Tanzania
 AL Afar Locality, Ethiopia
 ARA-VP Aramis Vertebrate Paleontology, Ethiopia
 BOU-VP Bouri Vertebrate Paleontology, Ethiopia
 TM Toros-Menalla, Chad

TM 266-01-060-1, "Toumai", Sahelanthropus tchadensis
Discovered by Ahounta Djimdoumalbaye in 2001 in Chad, in the southern Sahara desert. Estimated age is between 6 and 7 million years. This is a mostly complete cranium with a small brain (between 320 and 380 cc). (Brunet et al. 2002, Wood 2002) It has many primitive apelike features, such as the small brainsize, along with others, such as the brow ridges and small canine teeth, which are characteristic of later hominids.

"ARA-VP, Sites 1, 6 & 7", Ardipithecus ramidus
Discovered by a team led by Tim White, Berhane Asfaw and Gen Suwa (1994) in 1992 and 1993 at Aramis in Ethiopia. Estimated age is 4.4 million years. The find consisted of fossils from 17 individuals. Most remains are teeth, but there is also a partial lower jaw of a child, a partial cranium base, and partial arm bone from 2 individuals.
ARA-VP-6/1 consists of 10 teeth from a single individual.
ARA-VP-7/2 consists of parts of all three bones from the left arm of a single individual, with a mixture of hominid and ape features.

KP 271, "Kanapoi Hominid", Australopithecus anamensis
Discovered by Bryan Patterson in 1965 at Kanapoi in Kenya (Patterson and Howells 1967). This is a lower left humerus which is about 4.0 million years old. (Creationist arguments)

KP 29281, Australopithecus anamensis
Discovered by Peter Nzube in 1994 at Kanapoi in Kenya (Leakey et al. 1995). This is a lower jaw with all its teeth which is about 4.0 million years old.

KP 29285, Australopithecus anamensis
Discovered by Kamoya Kimeu in 1994 at Kanapoi in Kenya. This is a tibia, missing the middle portion of the bone, which is about 4.1 million years old. It is the oldest known evidence for hominid bipedalism.

AL 129-1, Australopithecus afarensis
Discovered by Donald Johanson in 1973 at Hadar in Ethiopia (Johanson and Edey 1981; Johanson and Taieb 1976). Estimated age is about 3.4 million years. This find consisted of portions of both legs, including a complete right knee joint which is almost a miniature of a human knee, but apparently belongs to an adult.

AL 288-1, "Lucy", Australopithecus afarensis
Discovered by Donald Johanson and Tom Gray in 1974 at Hadar in Ethiopia (Johanson and Edey 1981; Johanson and Taieb 1976). Its age is about 3.2 million years. Lucy was an adult female of about 25 years. About 40% of her skeleton was found, and her pelvis, femur (the upper leg bone) and tibia show her to have been bipedal. She was about 107 cm (3'6") tall (small for her species) and about 28 kg (62 lbs) in weight. (Creationist arguments)

AL 333 Site, "The First Family", Australopithecus afarensis?
Discovered in 1975 by Donald Johanson's team at Hadar in Ethiopia (Johanson and Edey 1981). Its age is about 3.2 million years. This find consisted of remains of at least 13 individuals of all ages. The size of these specimens varies considerably. Scientists debate whether the specimens belong to one species, two or even three. Johanson believes they belong to a single species in which males were considerably larger than females. Others believe that the larger specimens belong to a primitive species of Homo.

"Laetoli footprints", Australopithecus afarensis?
Discovered in 1978 by Paul Abell at Laetoli in Tanzania. Estimated age is 3.7 million years. The trail consists of the fossilized footprints of two or three bipedal hominids. Their size and stride length indicate that they were about 140 cm (4'8") and 120 cm (4'0") tall. Many scientists claim that the footprints are effectively identical to those of modern humans (Tattersall 1993; Feder and Park 1989), while others claim the big toes diverged slightly (like apes) and that the toe lengths are longer than humans but shorter than in apes (Burenhult 1993). The prints are tentatively assigned to A. afarensis, because no other hominid species is known from that time, although some scientists disagree with that classification. (Creationist arguments)

AL 444-2, Australopithecus afarensis
Discovered by Bill Kimbel and Yoel Rak in 1991 at Hadar in Ethiopia (Kimbel et al. 1994). Estimated age is 3 million years. This is a 70% complete skull of a large adult male, easily the most complete afarensis skull known, with a brain size of 550 cc. According to its finders, it strengthens the case that all the First Family fossils were members of the same species, because the differences between AL 444-2 and the smaller skulls in the collection are consistent with other sexually dimorphic hominoids.

KNM-WT 40000, Kenyanthropus platyops
Discovered by Justus Erus in 1999 at Lomekwi in Kenya (Leakey et al. 2001, Lieberman 2001). Estimated age is about 3.5 million years. This is a mostly complete, but heavily distorted, cranium with a large, flat face and small teeth. The brain size is similar to that of australopithecines. This fossil has considerable similarities with, and is possibly related to, the habiline fossil ER 1470.

Taung 1, "Taung Child", Australopithecus africanus
Discovered by Raymond Dart in 1924 at Taung in South Africa (Dart 1925). The find consisted of a full face, teeth and jaws, and an endocranial cast of the brain. It is between 2 and 3 million years old, but it and most other South African fossils are found in cave deposits that are difficult to date. The teeth of this skull showed it to be from an infant about 5 or 6 years old (it is now believed that australopithecines matured faster than humans, and that the Taung child was about 3). The brain size was 410 cc, and would have been around 440 cc as an adult. The large rounded brain, canine teeth which were small and not apelike, and the position of the foramen magnum(*) convinced Dart that this was a bipedal human ancestor, which he named Australopithecus africanus (African southern ape). Although the discovery became famous, Dart's interpretation was rejected by the scientific community until the mid-1940's, following the discovery of other similar fossils.

(*) Anatomical digression: the foramen magnum is the hole in the skull through which the spinal cord passes. In apes, it is towards the back of the skull, because of their quadrupedal posture. In humans it is at the bottom of the skull because our head is balanced on top of a vertical column. In australopithecines it is also placed forward from the ape position, although not always as far forward as in humans.

TM 1512, Australopithecus africanus (was Plesianthropus transvaalensis)
Discovered by Robert Broom in 1936 at Sterkfontein in South Africa (Broom 1936). The second australopithecine fossil found, it consisted of parts of the face, upper jaw and braincase.

Sts 5, "Mrs Ples", Australopithecus africanus
Discovered by Robert Broom in 1947 at Sterkfontein in South Africa. It is a very well preserved cranium of an adult. It has usually been thought to be female, but there has been a recent claim that it is male. It is the best specimen of africanus. It is about 2.5 million years old, with a brain size of about 485 cc. (It has recently been claimed that the fossils Sts 5 and Sts 14 (see next entry) were from the same individual)

Sts 14, Australopithecus africanus
Discovered by Robert Broom and J.T. Robinson in 1947 at Sterkfontein (Broom and Robinson 1947). Estimated age is about 2.5 million years. This find consisted of a nearly complete vertebral column, pelvis, some rib fragments, and part of a femur of a very small adult. The pelvis is more human than apelike, and is strong evidence that africanus was bipedal (Brace et al. 1979), although it may not have had the strong striding gait of modern humans (Burenhult 1993).

BOU-VP-12/130, Australopithecus garhi
Discovered by Yohannes Haile-Selassie in 1997 at Bouri in Ethiopia (Asfaw et al. 1999). This is a partial skull including an upper jaw with teeth which is about 2.5 million years old.

Stw 573, "Little Foot", Australopithecus
Discovered by Ron Clarke between 1994 and 1997 at Sterkfontein in South Africa. Estimated age is 3.3 million years. This fossil consists, so far, of many bones from the foot, leg, hand and arm, and a complete skull. More bones are thought to be still embedded in rock. (Clarke and Tobias 1995, Clarke 1998, Clarke 1999)

(An increasing number of scientists are placing the following three species, aethiopicus, robustus and boisei, in the genus Paranthropus)

KNM-WT 17000, "The Black Skull", Australopithecus aethiopicus
Discovered by Alan Walker in 1985 near West Turkana in Kenya. Estimated age is 2.5 million years. This find is an intact, almost complete cranium. The brain size is very small for a hominid, about 410 cc, and the skull has a puzzling mixture of primitive and advanced features. (Leakey and Lewin 1992)

TM 1517, Australopithecus robustus (was Paranthropus robustus)
Discovered by a schoolboy, Gert Terblanche, in 1938 at Kromdraai in South Africa (Broom 1938). It consisted of skull fragments, including five teeth, and a few skeletal fragments. This was the first specimen of robustus.

SK 48, Australopithecus robustus (was Paranthropus crassidens)
Discovered by Mr. Fourie in 1950 at Swartkrans in South Africa (Johanson and Edgar 1996). It is a cranium, probably belonging to an adult female, and 1.5-2.0 million years old. It is the most complete skull of robustus.

DNH 7, "Eurydice", Australopithecus robustus
Discovered by André Keyser in 1994 at the Drimolen cave in South Africa. Estimated age is between 1.5 and 2.0 million years. This is an almost complete skull and lower jaw of a female, one of the most complete hominid skulls ever found, and the first significant fossil of a female robustus. A fossil of a male robustus lower jaw, nicknamed Orpheus (DNH 8), was found a few inches away from it. (Keyser 2000)

OH 5, "Zinjanthropus", "Nutcracker Man", Australopithecus boisei
Discovered by Mary Leakey in 1959 at Olduvai Gorge in Tanzania (Leakey 1959). Estimated age is 1.8 million years. It is an almost complete cranium, with a brain size is about 530 cc. This was the first specimen of this species. Louis Leakey briefly considered this a human ancestor, but the claim was dropped when Homo habilis was found soon afterwards.

KNM-ER 406, Australopithecus boisei
Discovered by Richard Leakey in 1969 near Lake Turkana in Kenya. This find was a complete, intact cranium lacking only the teeth (Lewin 1987). Estimated age is about 1.7 million years. The brain size is about 510 cc. (see also ER 3733)

KNM-ER 732, Australopithecus boisei
Discovered by Richard Leakey in 1970 near Lake Turkana in Kenya. The cranium is similar to that of OH 5, but is smaller and has other differences such as the lack of a sagittal crest. The estimated age is about 1.7 million years. The brain size is about 500 cc. Most experts believe this is a case of sexual dimorphism, with the female being smaller than the male.

KGA10-525, Australopithecus boisei
Discovered by A. Amzaye in 1993 at Konso in Ethiopia (Suwa et al. 1997). This fossil consists of much of a skull, including a lower jaw. The estimated age is 1.4 million years. The brain size is estimated to be about 545 cc. Although it has many features specific to boisei, it also lies outside the previously known range of variation of that species in many ways, suggesting that boisei (and maybe other hominid species) may have been more variable than is often thought (Delson 1997).

Homo habilis
Discovered by the Leakeys in the early 1960's at Olduvai Gorge in Tanzania. A number of fragmentary specimens were found (Leakey et al. 1964).

· OH 7, "Jonny's Child", found by Jonathon Leakey in 1960 (Leakey 1961), consisted of a lower jaw and two cranial fragments of a child, and a few hand bones. Estimated age is 1.8 million years, and the brain size was about 680 cc.

· OH 8: found in 1960, consisted of a set of foot bones, complete except for the back of the heel and the toes. Estimated age is about 1.8 million years. They have a mixture of human and ape traits, but are consistent with bipedal locomotion. (Aiello and Dean 1990)

· OH 13, "Cindy": found in 1963, consisted of a lower jaw and teeth, bits of the upper jaw and a cranial fragment. Estimated age is 1.6 million years, and the brain size was about 650 cc.

· OH 16, "George": found in 1963, consisted of teeth and some very fragmentary parts of the skull. (George was unfortunately trampled by Masai cattle before he was found, and much of the skull was lost.) Estimated age is 1.7 million years, and the brain size was about 640 cc.

OH 24, "Twiggy", Homo habilis
Discovered by Peter Nzube in 1968 at Olduvai Gorge in Tanzania. It consisted of an fairly complete but very badly crushed cranium and seven teeth. It is about 1.85 million years old and has a brain size of about 590 cc.

KNM-ER 1470, Homo habilis (or Homo rudolfensis?)
Discovered by Bernard Ngeneo in 1972 at Koobi Fora in Kenya (Leakey 1973). Estimated age is 1.9 million years. This is the most complete habilis skull known. Its brain size is 750 cc, large for habilis. It was originally dated at nearly 3 million years old, a figure that caused much confusion as at the time it was older than any known australopithecines, from whom habilis had supposedly descended. A lively debate over the dating of 1470 ensued (Lewin 1987; Johanson and Edey 1981; Lubenow 1992). The skull is surprisingly modern in some respects. The braincase is much larger and less robust than any australopithecine skull, and is also without the large brow ridges typical of Homo erectus. It is however very large and robust in the face. A number of leg bones were found within a couple of kilometers, and are thought to probably belong to the same species. The most complete, KNM-ER 1481, consisted of a complete left femur, both ends of a left tibia and the lower end of a left fibula (the smaller of the two lower leg bones). These are quite similar to the bones of modern humans. (Creationist arguments)

KNM-ER 1805, "The Mystery Skull", Homo habilis??
Discovered by Paul Abell in 1973 at Koobi Fora in Kenya (Leakey 1974). Estimated age is 1.85 million years. This find consisted of much of a heavily built cranium containing many teeth. Its brain size is about 600 cc. Some features, such as the sagittal crest, are typical of A. boisei, but the teeth are too small for that species. (Willis 1989; Day 1986) Various workers have assigned it to almost every conceivable species, but many studies have attributed it to Homo habilis (e.g. Wood 1991). A recent cladistic study has placed it outside of Homo and most similar to robust australopithecines, though different from any named species. (Prat 2002)

KNM-ER 1813, Homo habilis
Discovered by Kamoya Kimeu in 1973 at Koobi Fora in Kenya (Leakey 1974). Estimated age is 1.8-1.9 million years. The brain size is 510 cc, which is very small for habilis, but the fossil is an adult specimen, probably of a female. Apart from its extremely small size, ER 1813 is surprisingly modern, with a rounded skull, no sagittal crest, modest eyebrow ridges, and a small amount of nasal prominence.

Stw 53, Homo habilis?
Discovered by Alun Hughes in 1976 at Sterkfontein in South Africa (Hughes and Tobias 1977). Estimated age is 1.5 to 2 million years. It consisted of a number of cranium fragments including teeth. Many stone tools were found in the same layer.

OH 62, "Dik-dik hominid", Homo habilis
Discovered by Tim White in 1986 at Olduvai Gorge in Tanzania (Johanson and Shreeve 1989; Johanson et al. 1987). Estimated age is 1.8 million years. The find consisted of portions of skull, arm, leg bones and teeth. Almost all the features of the skull closely resemble habilis fossils such as OH 24, ER 1813 and ER 1470, rather than the australopithecines. But the estimated height is very small, maybe about 105 cm (3'5"), and the arms are very long in proportion to the legs. These are australopithecine traits, and in fact the skeletal bones are very similar to those of Lucy. This find is significant because it is the only fossil in which limb bones have been securely assigned to habilis. Because of the small size, this was almost certainly a female. As with the australopithecines, males would have been considerably larger.

OH 65, Homo habilis
Discovered in 1995 at Olduvai Gorge in Tanzania. This fossil consisted of a complete upper jaw and part of the lower face, dated at 1.8 million years. Because of its similarities to the fossil ER 1470, its finders have suggested that OH 65 may lead to a reclassification of the habiline fossils. (Blumenschine et al. 2003, Tobias 2003)

Trinil 2, "Java Man", "Pithecanthropus I", Homo erectus (was Pithecanthropus erectus)
Discovered by Eugene Dubois in 1891 near Trinil on the Indonesian island of Java. Its age is uncertain, but thought to be about 700,000 years. This find consisted of a flat, very thick skullcap, and a few teeth (which may belong to orang-utans). The following year a femur was found about 12 meters away (Theunissen 1989). The brain size is about 940 cc. The femur is fully modern, and many scientists now believe that it belongs to a modern human. (Creationist arguments)

"Peking Man", Homo erectus (was Sinanthropus pekinensis)
Between 1929 and 1937, 14 partial craniums, 11 lower jaws, many teeth, some skeletal bones and large numbers of stone tools were discovered in the Lower Cave at Locality 1 of the Peking Man site at Zhoukoudian (formerly Choukoutien), near Beijing (formerly Peking), in China. Their age is estimated to be between 500,000 and 300,000 years old. (A number of fossils of modern humans were also discovered in the Upper Cave at the same site in 1933.) The most complete fossils, all of which were braincases or skullcaps, are:

· Skull III, discovered at Locus E in 1929 is an adolescent or juvenile with a brain size of 915 cc.

· Skull II, discovered at Locus D in 1929 but only recognized in 1930, is an adult or adolescent with a brain size of 1030 cc.

· Skulls X, XI and XII (sometimes called LI, LII and LIII) were discovered at Locus L in 1936. They are thought to belong to an adult man, an adult woman and a young adult, with brain sizes of 1225 cc, 1015 cc and 1030 cc respectively. (Weidenreich 1937)

· Skull V: two cranial fragments were discovered in 1966 which fit with (casts of) two other fragments found in 1934 and 1936 to form much of a skullcap with a brain size of 1140 cc. These pieces were found at a higher level, and appear to be more modern than the other skullcaps. (Jia and Huang 1990) (Creationist arguments)

Most of the study on these fossils was done by Davidson Black until his death in 1934. Franz Weidenreich replaced him and studied the fossils until leaving China in 1941. The original fossils disappeared in 1941 while being shipped to the United States for safety during World War II, but excellent casts and descriptions remain. Since the war, other erectus fossils have been found at this site and others in China.

Sangiran 2, "Pithecanthropus II", Homo erectus
Discovered by G.H.R. von Koenigswald in 1937 at Sangiran on the Indonesian island of Java. This fossil is a braincase that is very similar to the first Java Man skull cap, but more complete and smaller, with a brain size of only about 815 cc.

OH 9, "Chellean Man", Homo erectus
Discovered by Louis Leakey in 1960 at Olduvai Gorge in Tanzania (Leakey 1961). Estimated age is 1.5 million years. It consisted of a partial braincase with massive browridges and a brain size of 1065 cc.

OH 12, "Pinhead", Homo erectus
Discovered by Margaret Cropper in 1962 at Olduvai Gorge in Tanzania. It is similar to but less complete than OH 9, and smaller, with an estimated brain size of only 750 cc. It is estimated to be between 800,000 and 1200,000 years old. Anton (2004) has found a few more pieces of this skull, but it remains very fragmentary.

Sangiran 17, "Pithecanthropus VIII", Homo erectus
Discovered by Sastrohamidjojo Sartono in 1969 at Sangiran on Java. This consists of a fairly complete cranium, with a brain size of about 1000 cc. It is the most complete erectus fossil from Java. This skull is very robust, with a slightly projecting face and huge flaring cheekbones. It has been thought to be about 800,000 years old, but a recent dating has given a much older figure of nearly 1.7 million years. If the older date is correct, it means Homo erectus migrated out of Africa much earlier than previously thought.

KNM-ER 3733, Homo erectus (or Homo ergaster)
Discovered by Bernard Ngeneo in 1975 at Koobi Fora in Kenya. Estimated age is 1.7 million years. This superb find consisted of an almost complete cranium. The brain size is about 850 cc, and the whole skull is similar to the Peking Man fossils. The discovery of this fossil in the same stratum as ER 406 (A. boisei) delivered the coup de grace to the single species hypothesis: the idea that there has never been more than one hominid species at any point in history. (Leakey and Walker 1976)

KNM-WT 15000, "Turkana Boy", Homo erectus (or Homo ergaster)
Discovered by Kamoya Kimeu in 1984 at Nariokotome near Lake Turkana in Kenya (Brown et al. 1985; Leakey and Lewin 1992; Walker and Leakey 1993; Walker and Shipman 1996). This is an almost complete skeleton of an 11 or 12 year old boy, the only major omissions being the hands and feet. (Some scientists believe erectus matured faster than modern humans, and that he was really about 9 years old (Leakey and Lewin 1992).) It is the most complete known specimen of erectus, and also one of the oldest, at 1.6 million years. The brain size was 880 cc, and it is estimated that it would have been 910 cc at adulthood. The boy was 160 cm (5'3") tall, and would have been about 185 cm (6'1") as an adult. This is surprisingly tall, indicating that many erectus may have been as large as modern humans. Except for the skull, the skeleton is very similar to that of modern boys, although there are a number of small differences. The most striking is that the holes in his vertebrae, through which the spinal cord goes, have only about half the cross-sectional area found in modern humans. One suggested explanation for this is that the boy lacked the fine motor control we have in the thorax to control speech, implying that he wasn't nearly as fluent a speaker as modern humans are (Walker and Shipman 1996).

D2700, Homo georgicus
Discovered in 2001 at Dmanisi in Georgia. Estimated age is 1.8 million years. It consisted of a mostly complete skull, including a lower jaw (D2735) belonging to the same individual. (Vekua et al. 2002, Balter and Gibbons 2002) At around 600 cc, this is the smallest and most primitive hominid skull ever discovered outside of Africa. This skull and two others discovered nearby form a near-perfect transition between H. habilis and ergaster.

ATD6-69, Homo antecessor?
Discovered at Atapuerca in Spain. This is a partial face of a child who was probably about 10 to 11.5 years old. This fossil is over 780,000 years old. (Bermudez de Castro et al. 1997)

"Heidelberg Man", "Mauer Jaw", Homo sapiens (archaic) (also Homo heidelbergensis)
Discovered by gravel pit workers in 1907 near Heidelberg in Germany. Estimated age is between 400,000 and 700,000 years. This find consisted of a lower jaw with a receding chin and all its teeth. The jaw is extremely large and robust, like that of Homo erectus, but the teeth are at the small end of the erectus range. It is often classified as Homo heidelbergensis, but has also sometimes been considered to be a European Homo erectus.

"Rhodesian Man", "Kabwe", Homo sapiens (archaic) (was Homo rhodesiensis)
Discovered by a laborer in 1921 at Broken Hill in Northern Rhodesia (now Kabwe in Zambia) (Woodward 1921). This was a complete cranium that was very robust, with large brow ridges and a receding forehead. Estimated age is between 200,000 and 125,000 years. The brain size was about 1280 cc. (Creationist arguments)

Arago XXI, " Tautavel Man", Homo sapiens (archaic) (also Homo heidelbergensis)
Discovered at Arago in southern France in 1971 by Henry de Lumley. Estimated age is 400,000 years. The fossil consists of a fairly complete face, with 5 molar teeth and part of the braincase. The brain size was about 1150 cc. The skull contains a mixture of features from archaic Homo sapiens and Homo erectus, to which it is sometimes assigned.

Petralona 1, Homo sapiens (archaic)
Discovered by villagers at Petralona in Greece in 1960. Estimated age is 250,000-500,000 years. It could alternatively be considered to be a late Homo erectus, and also has some Neandertal characteristics. The brain size is 1220 cc, high for erectus but low for sapiens, and the face is large with particularly wide jaws. (Day 1986)

Atapuerca 5, Homo sapiens (archaic)
Discovered in the Sima de los Huesos ("Pit of Bones") at the Atapuerca cave site in northern Spain in 1992 and 1993 by Juan-Luis Arsuaga. It is about 300,000 years old, with a brain size of 1125 cc. The face is broad with a huge nasal opening, and resembles Neandertals in some traits but not in others. This is the most complete pre-modern skull in the entire hominid fossil record. (Arsuaga et al. 1993; Johanson and Edgar 1996)

Feldhofer, Neanderthal 1, Homo sapiens neanderthalensis
Discovered by Johann Fuhlrott in 1856 in a small cave at Feldhofer in the Neander Valley in Germany. The find consisted of a skullcap, thigh bones, part of a pelvis, some ribs, and some arm and shoulder bones. The lower left arm had been broken in life, and as a result the bones of the left arm were smaller than those of the right. Fuhlrott recognized it as a primitive human, but the German establishment headed by Rudolf Virchow rejected this view, incorrectly claiming that it was a pathological modern human. (Trinkaus and Shipman 1992) In 1999, the original site was rediscovered, and more bones from the same specimen were recovered. (Creationist arguments)

(There were actually two earlier Neandertal finds. A partial cranium of a 2.5 year old child found in 1829 in Belgium was not recognized until 1936. An adult cranium found on Gibraltar in 1848 gathered dust in a museum until it was recognized as a Neandertal in 1864.)

"Spy 1 and 2", Homo sapiens neanderthalensis
Discovered by Marcel de Puydt and Max Lohest in 1886 at the Grotto of Spy (pronounced Spee) d'Orneau in Belgium. Estimated age is about 60,000 years. This find consisted of two almost complete skeletons. The excellent descriptions of the skeletons established that they were very old, and largely discredited the idea that the Neandertal physique was a pathological condition, but also erroneously concluded that Neandertal Man walked with bent knees.

"Krapina Site", Homo sapiens neanderthalensis
Discovered by Dragutin Gorjanovic-Kramberger in 1899 near Krapina in Croatia. This site yielded significant remains from two to three dozen individuals, and teeth and jaw fragments from dozens more. When Gorjanovic published on his finds in 1906, it confirmed for once and for all that Neandertals were not pathological modern humans.

"Old Man", Homo sapiens neanderthalensis
Discovered by Amedee and Jean Bouyssonie in 1908 near La-Chapelle-aux-Saints in France. It is about 50,000 years old, with a brain size of 1620 cc. This nearly complete skeleton was reconstructed by Marcellin Boule, who wrote a definitive and highly influential paper on it which managed to be totally wrong in many of its conclusions. It exaggerated the apelike characteristics of the fossil, popularizing the stereotype, which would last for decades, of a stooping ape-man shuffling along on bent knees. This specimen was between about 30 and 40 when he died, but had a healed broken rib, severe arthritis of the hip, lower neck, back and shoulders, and had lost most of his molar teeth. The fact that he survived as long as he did indicates that Neandertals must have had a complex social structure.

"Shanidar Site", Homo sapiens neanderthalensis
Ralph Solecki discovered 9 Neandertal skeletons between 1953 and 1960 at the Shanidar cave in Iraq. They are thought to be between 70,000 and 40,000 years old. One of them, Shanidar 4, had apparently been buried with offerings of flowers (although this interpretation has been disputed). In 1971 Solecki wrote a book, "Shanidar, the First Flower People", reversing the earlier stereotypes of semi-human brutes. Another skeleton, Shanidar 1, was partially blind, one-armed and crippled. His survival also is evidence of a complex social structure.

"Saint-Cesaire Neandertal", Homo sapiens neanderthalensis
Discovered by Francois Leveque in 1979 near the village of Saint-Cesaire in France. It consisted of a badly crushed skeleton. The skull was mostly complete, with only the back of the cranium missing. It is dated at about 35,000 years old, and is one of the latest Neandertals known. This find was of special interest because it was found with tools that had previously been assumed to belong to the Cro-Magnon culture, instead of the usual Neandertal tool kit.

LB1, "Hobbit", Homo floresiensis
Discovered by an Australian/Indonesian team in 2003 at the Liang Bua cave on the Indonesian island of Flores. This find consisted of an almost complete skull and a partial skeleton consisting of leg bones, parts of the pelvis, hands and feet, and some other fragments. LB1 was an adult, probably female, about 1 meter (3'3") tall with an extremely small brain size of 417cc. The skull has human-like teeth with a receding forehead and no chin. The fossil is 18,000 years old and was found with stone tools. This species is thought to be a dwarf form of Homo erectus. (Brown et al. 2004, Morwood et al. 2004, Lahr and Foley 2004)

"Cro-Magnon Man", Homo sapiens sapiens (modern)
Discovered by workmen in 1868 at Cro-Magnon in France. Estimated age is 30,000 years. The site yielded skeletons of 5 buried individuals, along with stone tools, carved reindeer antlers, ivory pendants, and shells. The Cro-Magnons lived in Europe between 35,000 and 10,000 years ago. They are virtually identical to modern man, being tall and muscular and slightly more robust than most modern humans. They were skilled hunters, toolmakers and artists famous for the cave art at places such as Lascaux, Chauvet, and Altamira.

Summary

There are a number of clear trends (which were neither continuous nor uniform) from early australopithecines to recent humans: increasing brain size, increasing body size, increasing use of and sophistication in tools, decreasing tooth size, decreasing skeletal robustness. There are no clear dividing lines between some of the later gracile australopithecines and some of the early Homo, between erectus and archaic sapiens, or archaic sapiens and modern sapiens.

Despite this, there is little consensus on what our family tree is. Everyone accepts that the robust australopithecines (aethiopicus, robustus and boisei) are not ancestral to us, being a side branch that left no descendants. Whether H. habilis is descended from A. afarensis, africanus, both of them, or neither of them, is still a matter of debate. It is possible that none of the known australopithecines is our ancestor.

A number of new genera and species have been discovered within the last decade (Ar. ramidus, Au. amanensis, Au. bahrelghazali, Au. garhi, Orrorin, Kenyanthropus, Sahelanthropus) and no consensus has yet formed on how they are related to each other or to humans. It is generally accepted that Homo erectus is descended from Homo habilis (or, at least, some of the fossils often assigned to habilis), but the relationship between erectus, sapiens and the Neandertals is still unclear. Neandertal affinities can be detected in some specimens of both archaic and modern sapiens.

Fossil and Geologic Evidence: Fossil Evidence

"Lucy", a 3.2 Ma A. afarensis specimen that exhibits definitive bipedal morphology. Redrawn after Johanson and Edey 1981¹¹

Homo ergaster, specimen KNM ET 15000, is a nearly complete skeleton and exhibits many hallmarks of bipedalism, such as the bicondylar angle and longer legs relative to the arms.

The fossil records can help anthropologists determine the origins of bipedalism, which in turn allows us to understand which species might be direct ancestors to modern humans. One of the most abundant sources for early bipedalism is found in Australopithecus afarensis, a species that lived between 4 and 2.8 million years ago (Ma). The most famous fossil in the world, Lucy, is a member of the A. afarensis species and has provided a great deal of information on early bipedalism. For example, A. afarensis fossils clearly show hip and knee morphology distinctive to habitual bipedalism.

A. afarensis also left behind a 27 meter long set of footprints known as the Laetoli Tracks in Tanzania. Approximately 3.6 Ma, three A. afarensis individuals walked through a muddy layer of volcanic ash that perfectly preserved their foot prints as the ash cemented²⁰. From the Laetoli tracks it is clear that A. afarensis walked with an upright posture, with a strong heal strike and following through to the ball of the foot, with the big toe making last contact with the ground and pushing off. Interestingly, the prints provide evidence of a slight gap between the big toe and the rest of the toes. This gap suggests that even though the big toe was not divergent, it was not yet directly parallel with the rest of the toes like that seen in modern humans.^8-10,21-23

Though australopithecines are among the earliest hominins to have used habitual bipedalism, earlier hominins dating as far back as 7 million years also provide exciting evidence for early bipedalism. The oldest known hominin to definitively exhibit morphological (i.e. physical) adaptations for bipedal behavior is the extinct species Orrorin tugenensis that dates to 6 Ma. A femur and tibia recovered in Kenya assigned to O. tugenensis exhibits a bicondylar angle seen in habitual bipeds.^24-26 However, a recently discovered fossil specimen known as Sahelanthropus tchadensis from Chad, dating to approximately 7 Ma, shows a more inferiorly positioned foramen magnum consistent with bipedalism, rather than a more dorsal placement seen in modern quadrupeds.^27,28 There is no post-cranial material associated with Sahelanthropus, but if proven to be bipedal, Sahelanthropus may substantiate the hypothesis that the evolution of habitually bipedal hominins was initiated by climate trends beginning in the late Miocene (i.e., a geologic epoch that dates between 23 and 5.3 Ma). Analyses of fauna recovered from the same locations that these fossils were found suggests S. tchadensis and O. tugenensis lived on a lake margin, near the edge of woodland and more open country.

About 2 million years younger than O. tugenensis is a hominin known as known as Ardipithecus ramidus that dates to approximately 4.4 Ma. As with S. tchadensis, there is no post-cranial material associated with Ard. ramidus, and bipedalism has been determined based its more inferiorly positioned foramen magnum^8,10.

The oldest evidence of bipedalism in australopithecines is found in the species A. anamensis (4.2 to 3.9 Ma). Found in Kenya, A. anamensis most likely lived in a wooded savanna. Fossils evidence for this species includes a preserved tibia that exhibits bipedal characteristics such as such as a right angle between the shaft and the proximal surface, and proximal articular condyles of nearly equal size. An abundance of the younger species A. afarensis (4 to 2.8 Ma) and A. africanus (3 to 2 Ma) fossils also show clear signs of habitual bipedalism, including a bicondylar angle, an anteriorly placed foramen magnum, laterally flaring iliac blades, longer femoral necks and heads, and the presence of a lumbar curve. Though A. afarensis seems to have originated in Ethiopia and A. africanus is found only in South Africa, both of these species lived in open habitats, possibly wooded savanna areas near a lake^8-10.

Paranthropines are larger and more robust than australopithecines, but have similar post-cranial morphology, including bipedal adaptations similar to Australopithecus. The oldest paranthropine was found in Ethiopia and is known as P. aethiopicus (2.6 - 2.5 Ma). Although mostly cranial material has been recovered for this species, a newly discovered calcaneus that may be associated with this species appears adapted for bipedalism. The younger paranthropine species, P. robustus (1.75 to 1.5 Ma) and P. boisei (2.5 to 1 Ma), exhibit the same bipedal adaptations as A. africanus, which include an inferiorly oriented foramen magnum, modern human-like talus, longer femoral neck, and bicondylar angle. In addition, the hand anatomy of P. robustus implies a grip capable of tool use, while the radius of both P. robustus and P. boisei implies Paranthropus retained the ability to effectively climb trees. Paleoecological studies suggest these species were living in open woodland or savanna habitats^8-10.

All species included in the genus Homo are habitually bipedal and show evidence of tool use, beginning with the species H. habilis (i.e., "Handy Man") that dates between approximately 2.6 to 1.6 million years ago to the modern species H. sapiens that dates between approximately 190,000 years ago to the present^8-10.

Fossil Skeleton From Africa Predates Lucy

By JOHN NOBLE WILFORD

Published: October 1, 2009

Lucy, meet Ardi.

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Tim White, 2008, from the October 2 issue of Science

A fairly complete skeleton of Ardipithecus ramidus, which replaced Lucy as the earliest known skeleton from the human branch of the primate family tree. More Photos »

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Ardi, short for Ardipithecus ramidus, is the newest fossil skeleton out of Africa to take its place in the gallery of human origins. At an age of 4.4 million years, it lived well before and was much more primitive than the famous 3.2-million-year-old Lucy, of the species Australopithecus afarensis.

Since finding fragments of the older hominid in 1992, an international team of scientists has been searching for more specimens and on Thursday presented a fairly complete skeleton and their first full analysis. By replacing Lucy as the earliest known skeleton from the human branch of the primate family tree, the scientists said, Ardi opened a window to “the early evolutionary steps that our ancestors took after we diverged from our common ancestor with chimpanzees.”

The older hominid was already so different from chimps that it suggested “no modern ape is a realistic proxy for characterizing early hominid evolution,” they wrote.

The Ardipithecus specimen, an adult female, probably stood four feet tall and weighed about 120 pounds, almost a foot taller and twice the weight of Lucy. Its brain was no larger than a modern chimp’s. It retained an agility for tree-climbing but already walked upright on two legs, a transforming innovation in hominids, though not as efficiently as Lucy’s kin.

Ardi’s feet had yet to develop the arch-like structure that came later with Lucy and on to humans. The hands were more like those of extinct apes. And its very long arms and short legs resembled the proportions of extinct apes, or even monkeys.

Tim D. White of the University of California, Berkeley, a leader of the team, said in an interview this week that the genus Ardipithecus appeared to resolve many uncertainties about “the initial stage of evolutionary adaptation” after the hominid lineage split from that of the chimpanzees. No fossil trace of the last common ancestor, which lived some time before six million years ago, according to genetic studies, has yet come to light.

The other two significant stages occurred with the rise of Australopithecus, which lived from about four million to one million years ago, and then the emergence of Homo, our own genus, before two million years ago. The ancestral relationship of Ardipithecus to Australopithecus has not been determined, but Lucy’s australopithecine kin are generally recognized as the ancestral group from which Homo evolved.

Scientists not involved in the new research hailed its importance, placing the Ardi skeleton on a pedestal alongside notable figures of hominid evolution like Lucy and the 1.6-million-year-old Turkana Boy from Kenya, an almost complete specimen of Homo erectus with anatomy remarkably similar to modern Homo sapiens.

David Pilbeam, a professor of human evolution at Harvard University who had no role in the discovery, said in an e-mail message that the Ardi skeleton represented “a genus plausibly ancestral to Australopithecus” and began “to fill in the temporal and structural ‘space’ between the apelike common ancestor and Australopithecus.”

Andrew Hill, a paleoanthropologist at Yale University who was also not involved in the research, noted that Dr. White had kept “this skeleton in his closet for the last 15 years or so, but I think it has been worth the wait.” In some ways the specimen’s features are surprising, Dr. Hill added, “but it makes a very satisfactory animal for understanding the changes that have taken place along the human lineage.”

The first comprehensive reports describing the skeleton and related findings, the result of 17 years of study, are being published Friday in the journal Science. Eleven papers by 47 authors from 10 countries describe the analysis of more than 110 Ardipithecus specimens from a minimum of 36 different individuals, including Ardi.

The paleoanthropologists wrote in one of the articles that Ardipithecus was “so rife with anatomical surprises that no one could have imagined it without direct fossil evidence.”

A bounty of animal and plant material — “every seed, every piece of fossil wood, every scrap of bone,” Dr. White said — was gathered to set the scene of the cooler, more humid woodland habitat in which these hominids had lived.

This was one of the first surprises, said Giday WoldeGabriel, a geologist at Los Alamos National Laboratory, because it upset the hypothesis that upright walking had evolved as an adaptation to life on grassy savanna.

Published: October 4, 2009

CONSIDERED | Art by Lou Beach

The Hominid Sisterhood

Lou Beach

Lucy, you sweet young thing. No longer can you lay claim to being the oldest creature on the human branch of the primate family tree.

The honor goes to Ardi, who at 4.4 million years old has you beat by a little over a million. Her assembled bones were unveiled Thursday by scientists who had been analyzing the Ardipithecus specimen since fragments were found in Ethiopia in 1992.

The particulars: Taller and heavier than Lucy, she weighed about 120 pounds and stood four feet tall (yes, she probably walked upright, though she was still an agile tree-climber). Forget the high heels; her feet had no arches (Lucy’s did). Tim D. White of Berkeley, a leader of the study team, said, “We are getting so close to that common ancestor of hominids and chimps, and we’d love to find an earlier skeleton.”

Related Article »

Our Kinder, Gentler Ancestors

Ardi casts doubt on the notion that we have an innate killer instinct

By FRANS DE WAAL

Are humans hard-wired to be ruthlessly competitive or supportive of one another?

The behavior of our ape relatives, known as peaceful vegetarians, once bolstered the view that our actions could not be traced to an impulse to dominate. But in the late 1970s, when chimpanzees were discovered to hunt monkeys and kill each other, they became the poster boys for our violent origins and aggressive instinct.

I use the term "boys" on purpose because the theory was all about males without much attention to the females of the species, who just tagged along evolutionarily. It was hard to escape the notion that we are essentially "killer apes" destined to wage war forever.

Doubts about this macho origin myth have been on the rise, however, culminating in the announcement this past week of the discovery of a fossil of a 4.4 million year old ancestor that may have been gentler than previously thought. Considered close to the last common ancestor of apes and humans, this ancestral type, named Ardipithecus ramidus (or "Ardi"), had a less protruding mouth equipped with considerably smaller, blunter canine teeth than the chimpanzee's impressive fangs. This ape's canines serve as deadly knives, capable of slashing open an enemy's face and skin, causing either a quick death through blood loss or a slow one through festering infections. Wild chimps have been observed to use this weaponry to lethal effect in territorial combat. But the aggressiveness of chimpanzees obviously loses some of its significance if our ancestors were built quite differently. What if chimps are outliers in an otherwise relatively peaceful lineage?

A New Human Ancestor

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Reuters

A partial skeleton of Ardipithecus ramidus graces the cover of the latest issue of the journal Science.

Bone by Bone

Learn more about Ardipithecus ramidus.

View Interactive

Consider our other close relatives: gorillas and bonobos. Gorillas are known as gentle giants with a close-knit family life: they rarely kill. Even more striking is the bonobo, which is just as genetically close to us as the chimp. No bonobo has ever been observed to eliminate its own kind, neither in the wild nor in captivity. This slightly built, elegant ape seems to enjoy love and peace to a degree that would put any Woodstock veteran to shame. Bonobos have sometimes been presented as a delightful yet irrelevant side branch of our family tree, but what if they are more representative of our primate background than the blustering chimpanzee?

The assumption that we are born killers has been challenged from an entirely different angle by paleontologists asserting that the evidence for warfare does not go back much further than the agricultural revolution, about 15,000 years ago. No evidence for large-scale conflict, such as mass graves with embedded weapons, have been found from before this time. Even the walls of Jericho—considered one of the first signs of warfare and famous for having come tumbling down in the Old Testament—may have served mainly as protection against mudflows. There are even suggestions that before this time, about 70,000 years ago, our lineage was at the edge of extinction, living in scattered small bands with a global population of just a couple of thousand. These are hardly the sort of conditions that promote continuous warfare.

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Reuters

Apes at Play: Bonobo apes groom one another at a sanctuary in Congo.

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Corbis

Chimps at War: A male Eastern chimpanzees bares his teeth at Gombe National Park in Tanzania.

The once-popular killer ape theory is crumbling under its own lack of evidence, with "Ardi" putting the last nail in its coffin. On the other side of the equation, the one concerning our prosocial tendencies, the move has been towards increasing evidence for humans as cooperative and empathic. Some of this evidence comes from the new field of behavioral economics with studies showing that people do not always adhere to the profit principle. We care about fairness and justice and sometimes let these concerns override the desire to make as much money as possible. All over the world, people have played the "ultimatum game," in which one party is asked to react to the division of benefits proposed by another. Even people who have never heard of the French enlightenment and its call for égalité refuse to play along if the split seems unfair. They may accept a split of 60 for the proposer and 40 for themselves, but not a 80 to 20 split. They thus forgo income that they could have taken, which is something no rational being should ever do. A small income trumps no income at all.

Similarly, if one gives two monkeys hugely different rewards for the same task, the one who gets the short end of the stick refuses to cooperate. We hold out a piece of cucumber, which normally entices any monkey to perform, but with its neighbor munching on grapes cucumber is simply not good enough anymore. They protest the situation, sometimes even flinging those measly cucumber slices away, showing that even monkeys compare what they get with what others are getting.

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David L. Brill

Scientists Bruce Latimer and C. Owen Lovejoy analyze Ardipithecus ramidus fossils at the National Museum of Ethiopia in 1995.

Science Journal

Fossils Shed New Light on Human Past

And then there is the evidence for helping behavior, such as the consolation of distressed group members, which primates do by means of embracing and kissing. Elephants give reassuring rumbles to distressed youngsters, dolphins lift sick individuals to the surface where they can breathe, and almost every dog owner has stories of concerned reactions by their pets. In Roseville, Calif., a black Labrador jumped in front of his friend, a six-year-old boy, who was being threatened by a rattle snake. The dog took so much venom that he required blood transfusions to be saved.

The empathy literature on animals is growing fast, and is no longer restricted to such anecdotes. There are now systematic studies, and even experiments that show that we are not the only caring species. At the same time, we are getting used to findings of remarkable human empathy, such as those by neuroscientists that reward centers in the brain light up when we give to charity (hence the saying that "doing good feels good") or that seeing another in pain activates the same brain areas as when we are in pain ourselves. Obviously, we are hard-wired to be in tune with the emotions of others, a capacity that evolution should never have favored if exploitation of others were all that mattered.

— Frans de Waal, a professor of primate behavior in the psychology department at Emory University, is the author of "The Age of Empathy."

THE "HOBBITS" OF INDONESIA

1. Unusual features http://australianmuseum.net.au/Homo-floresiensis

Body size and shape

• very small stature of about 1 metre (the remains of 5 individuals were used for this average), which is less than the average for short populations of humans such as pygmies (who average about 1.4-1.5 m tall)
• the wide pelvis and hunched shoulders give it a different body shape compared with H. sapiens

Brain

• combination of features not seen in other hominin species
• has features that are not found in H. sapiens, particularly in the temporal and frontal lobes
• small brains averaging 380cc, about the size of a chimpanzee. This suggests there was active selection for a small brain size, possibly related to the reduced energy requirements of small brains.

Skull

• cranial shape is long and low and closer to that of H. erectus than H. sapiens
• receding and small forehead
• thick bones within the range of H. erectus and H. sapiens
• flat face
• brow ridges over each eye that do not form a continuous brow ridge as in Indonesian H. erectus

Jaws and teeth

• lacks the bony point on the chin found in modern humans
• relatively large jaw and teeth that resemble H. erectus but with more primitive features
• premolar roots different from H. sapiens
• small post-canine and canine teeth
• parabolic or V-shaped dental arcade typical of Homo
• bony shelf at the front of the lower jaw which is a primitive feature not seen in H. erectus

Limbs and pelvis

• bones and joints of the arm, shoulder and the lower limbs suggest that H. floresiensis was more similar to early humans than modern humans
• characteristic bipedal foot that includes a big toe aligned with other toes and a locking mechanism on the middle of the foot to help stiffen the arch after heel lift occurs
• several primitive features include a relatively long foot for its body size, a flat arch lacking the spring-like mechanism used to store and release energy during running, and a short big toe. These features are similar to ancient hominins such as H. habilis (OH8) and australopithecines
• features in the foot suggest the gait was different from and less efficient than modern humans
• unusual low twist in the upper arm bone
• wide leg bones compared to the length
• relatively short and curved clavicle
• shape of the shoulder blade resulted in the shoulder being moved forwards slightly as if hunched
• wrist bones differ significantly from the those of modern humans and are more similar to African apes or australopithecines. They lack features that evolved with the ancestors of modern humans at least about 800,000 years ago
• primitive flared ilium blades in the pelvis, and females have wider pelvises than H. sapiens females
• relatively long arms

2. “The first itinerant humans, Homo erectus, crossed land bridges from Asia to Indonesia. But their trail seemed to end at Java (above), the site of Homo erectus bones at least 1.5 million years old. No one believed these early humans could cross the ocean barrier called Wallace's line. Scientists thought it wasn't until 50,000 years ago that people—modern Homo sapiens—made the jump. But 840,000-year-old stone tools found in the Soa Basin on Flores are a sign that Homo erectus crossed Wallace's line much earlier. "How they managed to get there is still a real mystery," says Mike Morwood of the University of New England in Australia.” http://ngm.nationalgeographic.com/print/features/world/asia/georgia/flores-hominids-text

3. anthropology

· Homo floresiensis (in Homo floresiensis (extinct hominin))

They further hypothesized that the diminutive size of H. floresiensis may have been caused by island dwarfing, or endemic dwarfing, a process whereby some creatures confined to isolated habitats such as islands are known to have become smaller over time. Britannica

This effect has made itself manifest many times throughout natural history, including dinosaurs, like Europasaurus, and modern animals such as elephants. There are several proposed explanations for the mechanism which produces such dwarfism, which are often considered likely to be co-contributing factors. One explanation is an evolved gene-encoded response to environmental stress. Another is a selective process where only smaller animals trapped on the island survive, as food declines to a borderline level. The smaller animals need fewer resources, and so are more likely to get past the break-point where population decline allows food sources to replenish enough for the survivors to flourish. http://en.wikipedia.org/wiki/Insular_dwarfism

Dwarf elephants in the recent natural history of Malta, Crete, Cyprus, and Sicily.^[2]

4. Importantly, this new study continues to undermine claims that the 'hobbit' suffered from a medical condition known as microcephaly - that is, a modern human with an abnormally small brain - by looking at a part of the anatomy far removed from the head: namely, the wrist bones. "Microcephalics do not have unusually shaped wrist bones, but the hobbit does - and the features of the wrist bones are echoed in the primitive traits seen in many other parts of the skeleton, including the skull, which has been almost the sole focus of attention of the pro-microcephaly camp." http://www.telegraph.co.uk/science/science-news/3307640/Hobbits-of-Indonesia-were-different-human-species.html

“…Scientists at Florida State University in Tallahassee say that remains of Homo floresiensis, also known as hobbits, do not show any sign of growth disorders, refuting earlier claims that hobbits were pygmy Homo sapiens that suffered from a growth disorder. Lead researcher Dean Falk and her Florida State colleague Angela Schauber came to this conclusion after studying computer-generated reconstructions of the fossilized skulls of the small islanders. They suspect that Homo floresiensis especially as represented by a partial skeleton called LB1adapted to a challenging island environment by evolving into a smaller but proportionally equivalent version of an ancestral species, possibly Homo erectus. LB1 didn't have any of the growth pathologies that have been attributed to it, Falk said. A study unveiled last year suggested that LB1 exhibits 33 skeletal symptoms of Laron Syndrome, a type of insensitivity to growth hormones. Besides a reduction of face and limb size, this condition includes a round protrusion of the forehead and a depressed ridge on top of the nose. Falk, however, says that measurements, photos, and 3-D computer tomography reconstructions of LB1 do not show any similarity to published data on the anatomy of Laron Syndrome. She says that LB1 displays unique skull and tooth traits. She says that it also possesses whopping long feet relative to body size, in contrast to the typically small feet observed in Laron Syndrome. Apart from this, preliminary findings also show that LB1 did not suffer from one form of microcephaly, a genetic growth disorder, or from cretinism, a nutritionally influenced growth disorder… “ http://www.floresgirl.com/flores-island-hobbits-controversy.htm

5. “Today in the journal Science an analysis of three wrist bones of one of the fossil specimens (called LB1) led by Matthew Tocheri of the Smithsonian Institution, Washington, and including Prof Morwood and colleagues in Indonesia and America shows that the bones are primitive and shaped differently compared to both the wrist bones of both humans and of Neanderthals, suggesting they do represent a different kind of human. The Hobbit's wrist is basically indistinguishable from an African ape - nothing at all like that seen in modern humans and Neanderthals.Using cutting-edge 3D technology the team shows how there are big differences between the wrist bones of human - whether dwarf, normal or giant - and nonhuman primates, so the bones offer a powerful way to distinguish different species."This study offers one of the most striking confirmations of the original interpretation of the hobbit as an island remnant of one of the oldest human migrations to Asia," said Tocheri."Before I saw these wrist bones, I had no definitive opinion regarding the hobbit debates," said Tocheri. "But these hobbit wrist bones do not look anything like those of modern humans. They're not even close."For example, the human trapezoid is boot-shaped, while in LB1 the same bone is wedge-shaped. Also, the LB1 wrist bones are closer in shape to living african apes and earlier fossil species like australopithecus and Homo habilis.The team believes these differences imply that LB1has retained characteristics of a primitive wrist and thus represents a human lineage that appeared before the modern wrist evolved with Homo sapiens and the Neanderthals, who share an ancestor that lived between 0.5 and one million years ago.The distinctive shapes of wrist bones form during the first trimester of pregnancy while most growth disorders do not begin to affect the skeleton until well after that time. Thus, they argue, the hobbits are the descendants of an ancestor that had migrated out of Africa and branched off the human family tree before the branches that include modern humans, their cousins the Neanderthals and their last common ancestor.” http://www.telegraph.co.uk/science/science-news/3307640/Hobbits-of-Indonesia-were-different-human-species.html

For my prospective reference from Wikipedia, National Geographic with links:

Homo floresiensis

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A cast of a Homo floresiensis skull, American Museum of Natural History

Homo floresiensis Fossil range: Pleistocene
Conservation status
Extinct (IUCN 3.1)
Scientific classification
Domain:	Eukarya
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Primates
Family:	Hominidae
Tribe:	Hominini
Genus:	Homo
Species:	H. floresiensis
Binomial name
†Homo floresiensis

Homo floresiensis ("Flores Man"; nicknamed Hobbit) is a possible species in the genus Homo, remarkable for its small body and brain and for its survival until relatively recent times. It was named after the Indonesian island of Flores on which the remains were found.^[1][2] One largely complete subfossil skeleton (named LB1, because it was the first specimen found in the Liang Bua cave) and a complete jawbone from a second individual (LB2),^[3] dated at 18,000 years old, were discovered in deposits in Liang Bua Cave on Flores in 2003. Parts of seven other individuals (LB3–LB9; the most complete is LB6), all diminutive, have been recovered as well as similarly small stone tools from horizons ranging from 94,000 to 13,000 years ago.^[4] Descriptions of the remains were first published in October 2004.^[1][2] To date, the only complete cranium is that of LB1.

The discoverers (anthropologists Peter Brown, Michael Morwood and their colleagues) have argued that a variety of features, both primitive and derived, identified the skeleton of LB1 as that of a new species, H. floresiensis, of the Hominini tribe that currently comprises humans (Homo) and two species of chimpanzee (Pan), their ancestors, and the extinct lineages of their common ancestor.^[1][2] They argued that it lived contemporaneously with modern humans (Homo sapiens) on Flores.

Doubts that the remains constitute a new species were soon voiced by the Indonesian anthropologist Teuku Jacob, who suggested that the skull of LB1 was a microcephalic modern human. A controversy developed, leading to the publication of a number of studies which supported or rejected claims for species status. In March 2005 scientists who published details of the brain of Flores Man in Science supported species status.^[5] Several researchers, including one scientist who worked on the initial study, have disputed the 2005 study, supporting the conclusion that the skull is microcephalic.^[6][7] The original discoverers have argued against these interpretations and maintain that H. floresiensis is a distinct species.^[4][8] This is supported by a recent study published by paleoneurologist Dean Falk and her colleagues that disputes the possibility of microcephaly.^[9] They compared the H. floresiensis brain to ten microcephalic brains, and revealed distinct differences. In addition, a 2007 study of carpal bones of H. floresiensis found similarities to those of a chimpanzee or early hominin such as Australopithecus and significant differences from the bones of modern humans.^[10] Studies of the bones and joints of the arm, shoulder and the lower limbs have also suggested that H. floresiensis was more similar to early humans and apes than modern humans.^[11][12] However, critics of the claim to species status continue to suggest alternative explanations. One recent hypothesis is that the individuals were born without a functioning thyroid, resulting from a type of endemic cretinism (myxoedematous, ME).^[13]

A study^[14] published in July 2009 found that cladistic analysis supports that H. floresiensis is a separate species.

Contents

[hide]

• 1 Discovery
• 2 Anatomy
• 2.1 Small bodies
• 2.2 Small brains
• 2.3 Additional features
• 3 Recent survival
• 4 Controversies
• 4.1 Evidence against microcephaly
• 4.2 Laron syndrome
• 4.3 Bone structure
• 4.4 Endemic cretinism hypothesis
• 4.5 Cladistic Analysis
• 5 See also
• 6 References and Notes
• 7 Further reading
• 8 External links

[edit] Discovery

Cave on Flores Island where the specimens were discovered.

Flores Island in Indonesia, shown highlighted in red

The first specimens were discovered by a joint Australian-Indonesian team of paleoanthropologists and archaeologists looking for evidence of the original human migration of H. sapiens from Asia to Australia.^[1][2] They were not expecting to find a new species, and were surprised at the recovery of a nearly complete skeleton of a hominid they dubbed LB1 from the Liang Bua limestone cave on Flores. Subsequent excavations recovered seven additional skeletons, dating from 38,000 to 13,000 years ago.^[4] An arm bone, provisionally assigned to H. floresiensis, is about 74,000 years old. Sophisticated stone implements of a size considered appropriate to the 1 m tall human are also widely present in the cave. These are at horizons from 95,000 to 13,000 years ago and are associated with juvenile Stegodon (a group of proboscideans that was widespread throughout Asia during the Quaternary), presumably the prey of LB1.^[4] They also shared the island with giant rats, Komodo dragons, and even larger species of lizard.^[15] Homo sapiens had reached the region by around 45,000 years ago.^[16]

The specimens are not fossilized, but were described by Richard Roberts of the University of Wollongong, Australia as having "the consistency of wet blotting paper"^[17] (once exposed, the bones had to be left to dry before they could be dug up). Researchers hope to find preserved mitochondrial DNA to compare with samples from similarly unfossilised specimens of Homo neanderthalensis and H. sapiens.^[17]

[edit] Anatomy

The most important and obvious identifying features of H. floresiensis are its small body and small cranial capacity. Brown and Morwood also identified a number of additional, less obvious features that might distinguish LB1 from modern H. sapiens, including the form of the teeth, the absence of a chin, and the unusually low twist in the forearm bones. Each of these putative distinguishing features has been heavily scrutinized by the scientific community, with different independent research groups reaching differing conclusions whether these features support the original designation of a new species,^[8] or whether they identify LB1 as a severely pathological H. sapiens.^[7] The discovery of additional partial skeletons^[4] has verified the existence of some features found in LB1, such as the lack of a chin, but Jacob and other research teams argue that these features do not distinguish LB1 from local H. sapiens morphology.^[7] Recent research of Lyras et al.,^[18] based on 3D-morphometrics, shows that the skull of LB1 differs significantly from all H. sapiens skulls, including those of small-bodied individuals and microcephalics, and is similar only to the skull of Homo erectus.

[edit] Small bodies

The type specimen for the proposed species is a fairly complete skeleton and near-complete skull proposed to be that of a 30-year-old female (LB1), nicknamed Little Lady of Flores or Flo, about 1.06 m (3 ft 6 in) in height.^[1] This short stature is also supported by the height estimates derived from the tibia of a second skeleton (LB8), on the basis of which Morwood and colleagues suggest that LB8 might have stood 1.09 m (3 ft 7 in) high.^[4] These estimates are outside the range of normal modern human height and considerably shorter than the average adult height of even the physically smallest populations of modern humans, such as the African Pygmies (< 1.5 m, or 4 ft 11 in),^[19] Twa, Semang (1.37 m, or 4 ft 6 in for adult women),^[20] or Andamanese (1.37 m, or 4 ft 6 in for adult women).^[21] Mass is generally considered more biophysically significant than a one-dimensional measure of length, and by that measure, due to effects of scaling, differences are even greater. LB1 has been estimated as perhaps about 25 kg (55 lb). This is smaller than not only modern H. sapiens, but also than H. erectus, which Brown and colleagues have suggested is the immediate ancestor of H. floresiensis. LB1 and LB8 are also somewhat smaller than the ancestor australopithecines, from three million years ago, not previously thought to have expanded beyond Africa. Thus, LB1 and LB8 may be the shortest and smallest members of the extended human family discovered thus far.

Despite the size difference, the specimens seem otherwise to resemble in their features H. erectus, known to be living in Southeast Asia at times coincident with earlier finds purported to be of H. floresiensis.^[4] These observed similarities form the basis for the suggested phylogenetic relationship. Controversially, the same team is reported to have found material evidence, stone tools, of a H. erectus occupation 840,000 years ago, but actual remains of H. erectus itself have not been found on Flores, much less transitional forms.

To explain the small stature of H. floresiensis, Brown and colleagues have suggested that in the limited food environment on Flores H. erectus underwent strong insular dwarfism,^[1] a form of speciation also seen on Flores in several species, including a dwarf Stegodon, as well as being observed on other small islands. However, the "island dwarfing" theory has been subjected to some criticism from Teuku Jacob and colleagues^[7] who argue that LB1 is similar to local Rampasasa H. sapiens populations, and who point out that size can vary substantially in pygmy populations.

[edit] Small brains

In addition to a small body size, H. floresiensis had a remarkably small brain. The type specimen, at 380 cm³ (23 in³), is at the lower range of chimpanzees or the extinct australopithecines.^[1][5] The brain is reduced considerably relative to this species' presumed immediate ancestor H. erectus, which at 980 cm³ (60 in³) had more than double the brain volume of its alleged descendant species.^[5] Nonetheless, the estimated brain to body mass ratio of LB1 lies between that of H. erectus and the great apes.^[22] Insular dwarfism is challenging explanation of brain size reduction.^[23]

Indeed, the discoverers have associated H. floresiensis with advanced behaviors. There is evidence of the use of fire for cooking in Liang Bua cave, and evidence of cut marks on the Stegodon bones associated with the finds.^[2][4] The species has also been associated with stone tools of the sophisticated Upper Paleolithic tradition typically associated with modern humans, who at 1310–1475 cm³ (80–90 in³) nearly quadruple the brain volume of H. floresiensis (with body mass increased by a factor of 2.6). Some of these tools were apparently used in the necessarily cooperative hunting of local dwarf Stegodon by this small human species.^[4]

An indicator of intelligence is the size of region 10 of the dorsomedial prefrontal cortex, which is associated with self-awareness and is about the same size as that of modern humans, despite the much smaller overall size of the brain.^[5]

[edit] Additional features

Additional features used to argue that the finds come from a population of previously unidentified hominids include the absence of a chin, the relatively low twist of the arm bones, and the width of the leg bones relative to their length.^[1][2][4] The presence of each of these features has been confirmed by independent investigators^[7] but their significance has been disputed.

In 2007, Susan G. Larson et al. focused on the twist of the nearly complete upper arm bone of the LB1’s skeleton.^[11] Modern people have the top of the bone twisted between 145 to 165 degrees, which makes the inner part of the elbow face slightly forward. Larson originally stated that the LB1’s bone was twisted only 110 degrees,^[24] but later made a new measurement and found that the torsion was 120 degrees. This could be an advantage when arm-swinging, but complicates activities associated with modern people, such as tool-making. Larson et al. investigated also the pectoral girdle of H. floresiensis. Due to the incomplete material they studied a broken clavicle of LB1 and a shoulder blade of the individual referred to as LB6. The clavicle was relatively short, which in combination with the shape of the shoulder blade and the low twist of the arm bone resulted in the shoulder being moved forwards slightly, as if it was shrugged. Thus H. floresiensis could bend the elbow in the way modern people do and Larson concluded that it could have been able to make tools as well.^[11]

In September 2007, Matthew W. Tocheri of the Smithsonian's National Museum of Natural History and his team published a paper on the wrist of H. floresiensis. They studied three complete carpal bones, a trapezoid, scaphoid and capitate, believed to belong to LB1. Tocheri et al. found that the shapes of these bones differ significantly from the bones of modern human wrist and that they resemble the wrist of great African apes or Australopithecus.^[10]

Jungers et al., who published a study on the lower limbs,^[25] found that H. floresiensis’ feet were unusually flat and large in comparison with the rest of the body. As a result, when walking, it would have to bend its knees further back than modern people do. According to Jungers, its walk resembled a sort of high stepped gait and it was not able to walk very fast. H. floresiensis also had unusual shape of its toes and its big toe was very short.^[26]

[edit] Recent survival

The species is thought to have survived on Flores until at least as recently as 12,000 years ago making it the longest-lasting non-modern human, surviving long past the Neanderthals (H. neanderthalensis) which became extinct about 24,000 years ago.^[4]

Due to a deep neighboring strait, Flores remained isolated during the Wisconsin glaciation (the most recent glacial period), despite the low sea levels that united much of the rest of Sundaland. This has led the discoverers of H. floresiensis to conclude the species, or its ancestors, could only have reached the isolated island by water transport, perhaps arriving in bamboo rafts around 100,000 years ago (or, if they are H. erectus, then about 1 million years ago). This idea of Flores using advanced technology and cooperation on a modern human level has prompted the discoverers to hypothesize that H. floresiensis almost certainly had language.^[27] These suggestions have been some of the most controversial of the discoverers' findings.

Local geology suggests that a volcanic eruption on Flores approximately 12,000 years ago was responsible for the demise of H. floresiensis, along with other local fauna, including the dwarf elephant Stegodon.^[2] Gregory Forth hypothesized that this species may have survived longer in other parts of Flores to become the source of the Ebu Gogo stories told among the local people. The Ebu Gogo are said to have been small, hairy, language-poor cave dwellers on the scale of H. floresiensis.^[28] Believed to be present at the time of the arrival of the first Portuguese ships during the 16th century, these creatures are claimed to have existed as recently as the late 19th century.^[29] Gerd van den Bergh, a paleontologist working with the fossils, reported hearing of the Ebu Gogo a decade before the fossil discovery.^[30] On the island of Sumatra, there are reports of a 1–1.5 m tall humanoid, the Orang Pendek, which paleontologist Henry Gee has speculated might be related to H. floresiensis.^[31]

[edit] Controversies

Whether the specimens represent a new species is a controversial issue within the scientific community. Professor Teuku Jacob, chief paleontologist of the Indonesian Gadjah Mada University, and other scientists reportedly disagree with the placement of the new finds into a new species of Homo. Instead, Jacob proposed that they were members of "…a sub-species of Homo sapiens classified under the Austrolomelanesid race".^[32] He contended that the find is from a 25–30 year-old omnivorous subspecies of H. sapiens, and not a 30-year-old female of a new species. He is convinced that the small skull is that of a mentally defective modern human, probably a Pygmy, suffering from the genetic disorder microcephaly, which produces a small brain and skull.

In early December 2004, Jacob removed most of the remains from Soejono's institution, Jakarta's National Research Centre of Archaeology, for his own research without the permission of the Centre's directors.^{[33][34][35][36]} Some expressed fears that, like the Dead Sea scrolls, important scientific evidence would be sequestered by a small group of scientists who neither allowed access by other scientists nor published their own research. Jacob eventually returned the remains with portions severely damaged^[37] and missing two leg bones on February 23, 2005^[38] to the worldwide consternation of his peers. Reports noted the condition of the returned remains; "[including] long, deep cuts marking the lower edge of the Hobbit's jaw on both sides, said to be caused by a knife used to cut away the rubber mould"; "the chin of a second Hobbit jaw was snapped off and glued back together. Whoever was responsible misaligned the pieces and put them at an incorrect angle"; and, "The pelvis was smashed, destroying details that reveal body shape, gait and evolutionary history"^[39] and causing the discovery team leader Morwood to remark "It's sickening, Jacob was greedy and acted totally irresponsibly".^[37] Jacob, however, denied any wrongdoing. He stated that such damages occurred during transport from Yogyakarta back to Jakarta^[39] despite the physical evidence to the contrary that the jawbone had been broken while making a mold of bones.^[37]

In 2005 Indonesian officials forbade access to the cave and thus no other excavations in the place were possible. Some media, such as the BBC, expressed the opinion that the reason of the restriction was to protect Jacob, who was considered "Indonesia's king of palaeoanthropology", from being proven to be wrong. Scientists were allowed to return to the cave in 2007.^[39]

Prior to Jacob's removal of the fossils, a CT scan was taken of the skull and in 2005, a computer-generated model of the skull of H. floresiensis was undertaken, and analysed by a team headed by Dean Falk of Florida State University. The results were published in Science in February 2005. The authors of the study claimed that the brainpan was not that of a pygmy nor an individual with a malformed skull and brain, supporting the view that it is a new species.^[5] However, in October 2005 Science published an additional study headed by Alfred Czarnetzki, Carsten M. Pusch and Jochen Weber. This disagreed with the findings of the earlier study and concluded that the skull of LB1 is consistent with microcephaly.^[40]

The results of the February 2005 study were also questioned in the May 19, 2006, issue of the journal Science, in which Robert D. Martin of the Field Museum in Chicago and co-authors argued that the 2005 study had not compared the skull with a typical example of adult microcephaly. Martin and his co-authors concluded that the skull was probably microcephalic. Martin argued that the brain is far too small to be a separate dwarf species; if it were, he wrote, the 400-cubic-centimeter brain would indicate a creature only one foot in height, which would be one-third the size of the discovered skeleton.^[41] In the September 5, 2006, issue of the Proceedings of the National Academy of Sciences, a group of scientists from Indonesia, Australia, and the United States came to the same conclusion as Dr. Martin (i.e. that the skull is of a microcephalic human rather than a separate species) by examining bone and skull structure.^[7]

[edit] Evidence against microcephaly

A cast of LB1 (left) was compared to several microcephalic skulls, amongst which that of the microcephalic (right) used by Henneman in his attempt to present LB1 as a microcephalic. Argue (2006) and Lyras (2008) contend the opposite

In response, Brown and Morwood have criticized these recent findings by claiming that the scientists came to incorrect conclusions about bone and skull structure and mistakenly attributed the height of H. floresiensis to microcephaly.^[42] They also pointed to studies by other scientists who rejected the argument that the individual was diseased. Falk's team replied to the critics of their study, standing by their results and insisting that the skull is very different from microcephalic specimens.^[22] William Jungers, a morphologist from Stony Brook University, examined the skull and concluded that the skeleton displays "no trace of disease". However, Jochen Weber of the Leopoldina Hospital in Schweinfurt argues that "we can't rule out the possibility that he suffered from microcephaly".^[43] Debbie Argue of the Australian National University has also published a study in the Journal of Human Evolution which rejects microcephaly and concludes that the finds are indeed a new species.^[44]

On January 29, 2007, Falk published a new study supporting the claim to species status^[9] offering the most conclusive evidence to date that the claims of a microcephalic H. sapiens were not credible. In this new study Falk examines 3D computer generated models of an additional 9 microcephalic brains and 10 normal human brains, and reveals that the floresiensis skulls have a shape more aligned with normal human brains, but also have unique features which are consistent with what one would expect in a new species. Comparing the frontal and temporal lobes, as well as the back of the skull, revealed a brain highly developed, completely unlike the microcephalic brain, and advanced in ways different from modern human brains. This finding also answered past criticisms that the floresiensis brain was simply too small to be capable of the intelligence required to create the tools found in their proximity. Falk concludes the onus is now upon the critics that continue to claim microcephaly to produce a brain of a microcephalic that bears resemblance to the floresiensis brain.

The above mentioned study by Lyras et al. (2008) confirms Falk's results in that 3D-morphometric features of the skulls of microcephalic H. sapiens indeed fall within the range of normal H. sapiens and that the LB1 skull falls well outside this range. This means that LB1 cannot be attributed to a microcephalic H. sapiens, neither based on brain morphology nor on skull morphology.^[18]

[edit] Laron syndrome

The possibility that the skeletons from Flores are the remains of people who suffered from Laron syndrome was first proposed by American anatomist Gary D. Richards in June 2006.^[45] A year later, in June 2007, Israel Hershkovitz, Liora Kornreich and Zvi Laron from the Tel Aviv University in Israel published a new paper arguing that the morphological features of H. floresiensis are essentially indistinguishable from those of Laron syndrome.^[46] Laron syndrome causes severe pituitary dwarfism. Unlike growth hormone deficiency, growth hormone levels are increased,^[47] but the body is unresponsive to it.^[48] Its features include underdeveloped skull with small face and mandible and other skeletal changes. The disease is most often reported with Middle East children of consanguineous parents,^[47] but it also occurs in some South-East Asian countries.^[46]

The Israeli researchers compared X-rays of Israelis affected with Laron syndrome, whose heights ranged between 108 and 128 cm, with data from LB1.^[48] They compared 36 features from around the skeleton and concluded that most features were similar,^[45] including a pronounced ridge above the eyes, absence of a particular sinus, and short limbs in proportion to the trunk.^[48] They declared that Laron syndrome patients also have smaller heads, although not as small as LB1, and that many of the unique anatomical landmarks that Dean Falk had found left by the brain on the inner part of the LB1's skull, could have also been a feature of Laron syndrome.^[45][46] People with Laron syndrome also have a dense mastoid region bone, unlike healthy individuals, whose bone in this part of the skull is spongy and filled with air. Hershkovitz did not make this comparison, because no radiographs of LB1's skull were available.^[45][46] However, Falk examined the CT scans her team had made and found that LB1's mastoid region does not manifest any signs of Laron syndrome.^[49]

[edit] Bone structure

The bone structure of H. floresiensis’ shoulders, arms^[11] and wrists^[10] have been described as very different from modern humans, much closer to the bone structure of chimpanzees or an early hominin. This adds support to the idea that the Hobbit is a separate species of early human rather than a modern human with a physical disorder.

Susan G. Larson et al. analyzed the upper limb of LB1. They found that LB1’s arm torsion is unusually low, much lower than with modern people. This had been previously studied by G. D. Richards et al., who declared that it is a sign of modern pygmy populations, and T. Jacob et al., who pointed out that muscle attachments on the bone suggest LB1 had weak muscles which resulted in little development of humeral torsion. Larson et al. opposed Richards’ conclusion, arguing that pygmy populations usually have arm bones similarly twisted as average stature peoples. They argued that Richards et al. cited a 1972 paper which had studied a sample of six female Eastern Central African pygmies and this sample was too small to represent the whole population. Larson et al. also looked for some signs of microcephaly on the studied bones, but failed to find any.^[11]

William L. Jungers of the Stony Brook University in New York compared the low twist of the arm bone of H. floresiensis to the similarly small humeral torsion of an early hominid from Dmanisi in Georgia,^[50] usually designated as Homo georgicus. Larson et al. also studied a relatively short clavicle and unusual formation of the pectoral girdle. They compared their finding with a H. erectus skeleton, KNM-WT 15000, known as Nariokotome Boy, and suggested that the pectoral girdle of H. floresiensis was a transitional stage in human shoulder evolution.^[11]

While some specialists, including paleoanthropologist Russell Ciochon of the University of Iowa, supported the conclusion, others, including Eric Delson of Lehman College, City University of New York, pointed out that the recent sample of H. floresiensis individuals is too small and that Larson’s research was based just on one shoulder bone.^[24]

Another study supporting the separate species hypothesis was published by Matthew Tocheri et al., who studied H. floresiensis wrist bones. They compared three carpal bones believed to belong to LB1 with carpal bones of modern humans, some earlier hominids and African apes. They concluded that the carpals from the Liang Bua cave resembled ape carpal bones and were significantly different from the bones of H. sapiens, Homo neanderthalensis or even Homo antecessor, and that they were comparable to carpal bones of Australopithecus. The carpal bones of H. floresiensis lack features that evolved with ancestors of modern humans at least about 800,000 years ago. These features are already formed during embryogenesis and therefore Tocheri et al. argue that it is improbable that the shape of H. floresiensis wrist bones could be a result of a developmental disease.^[10]

This conclusion was challenged by Robert Martin of the Field Museum in Chicago, who noted that no research of wrists of microcephalic people had been done.^[51] Alan Thorne of the Australian National University stated that the differences were small and similar variation could occur with living modern humans. He also pointed out that the carpal bones had been found scattered in the cave and it was not certain that they all belonged to the same individual.^[52] Michael Morwood of the University of Wollongong in Australia, one of the co-authors of the study, opposed Thorne stating that there were also other features, such as the stature, body proportions, brain size, shoulder, pelvis, jaw and teeth which suggested that H. floresiensis is a separate species that evolved in isolation on the island.^[52]

The new species theory was supported also by a study on H. floresiensis’ lower limbs by William L. Jungers and his team (consisting mostly of the same scientists who had authored the upper limbs study).^[25] One of the most notable differences in the structure of the lower limb bones was unusually flat and large feet in comparison with the rest of the body. The big toe was described unusually short, similar to earlier hominids, including Australopithecus.^[26] Anthropologist Henry McHenry of the University of California declared that Jungers’ findings could end discussions on any disease hypothesis. According to him a bigger mystery is where H. floresiensis originated.^[26] John Hawks of the University of Wisconsin–Madison remained unconvinced, stating that the study did not perform enough comparison of the described features with various modern pygmy populations.^[49]

[edit] Endemic cretinism hypothesis

In 2008 Australian researchers Peter J. Obendorf, Charles E. Oxnard, and Ben J. Kefford suggested that LB1 and LB6 suffered myxoedematous (ME) endemic cretinism resulting from congenital hypothyroidism and that they were part of an affected population of H. sapiens on the island.^[13] This disease, caused by various environmental factors including iodine deficiency, is a form of dwarfism which can still be found among the local Indonesian population. Affected people, who were born without a functioning thyroid, have both small bodies and reduced brain size but their mental retardation and motor disability is not as severe as with neurological endemic cretins. According to the authors of the study, the critical environment could have been present on Flores approximately 18,000 years ago, the period to which the LB fossils are dated. They wrote that various features found on the fossils, such as enlarged pituitary fossa,^[13] unusually straight and untwisted top of the upper arm bone and relatively thick limbs,^[53] are a sign of this diagnosis. The double rooted lower premolar and primitive wrist morphology can be explained in this way as well. The oral stories about strange human-like creatures may also be a record of cretinism.^[13]

R. D. Martin has expressed his delight that other researchers continue to explore the possibility that the small skull is in fact a pathological specimen, but he still prefers the microcephaly hypothesis. Dean Falk challenged the Australian team's results, studying computer tomography scans of LB1's pituitary fossa and coming to the conclusion that it is not larger than usual. Because the fossa size was the key argument of the study on ME endemic cretinism, Falk dismissed the whole hypothesis. Peter Brown, the discoverer of the fossils, declared that the remains of the pituitary fossa were very poorly preserved and no meaningful measurement was possible.^[53] Other measurements of Obendorf et al. were also disputed, since they had neither the bones nor CT scans available and used just captured images from X-ray scans presented in the 2005 BBC show The Mystery of the Human Hobbit.^[54]

[edit] Cladistic Analysis

A study published in July 2009, by a team led by Debbie Argue, used cladistic analysis to suggest that the remains are from a separate species of Homo.^[14] The study describes two equally possible phylogenetic trees; one indicates H. floresiensis emerged between H. rudolfensis (1.86 Ma) and H. habilis (1.66-1.9 Ma), with the second tree indicating that H. floresiensis emerged after H. habilis.

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Insular dwarfism

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The skeleton of a dwarf elephant from the island of Crete.

Insular dwarfism, a form of Phyletic dwarfism,^[1] is the process and condition of the reduction in size of large animals – almost always mammals – when their gene pool is limited to a very small environment, primarily islands. The intentional breeding of insular dwarfism is called dwarfing.

This effect has made itself manifest many times throughout natural history, including dinosaurs, like Europasaurus, and modern animals such as elephants.

There are several proposed explanations for the mechanism which produces such dwarfism, which are often considered likely to be co-contributing factors. One explanation is an evolved gene-encoded response to environmental stress. Another is a selective process where only smaller animals trapped on the island survive, as food declines to a borderline level. The smaller animals need fewer resources, and so are more likely to get past the break-point where population decline allows food sources to replenish enough for the survivors to flourish.

Contents

[hide]

• 1 Examples
• 2 Additional examples
• 3 See also
• 4 References
• 5 External links

[edit] Examples

Among the most famous examples of insular dwarfism are:

• Dinosaurs, including the recently validated Europasaurus, on Mesozoic islands such as Haţeg Island. Other dwarf dinosaurs mainly from Haţeg Island, Romania, include Magyarosaurus, Rhabdodon and Telmatosaurus.
• A dwarf form of crocodile from the Early Cretaceous Period is Bernissartia, which grew no bigger than a domestic cat.
• Dwarf ground sloths in the recent natural history of Cuba, Hispaniola, and Puerto Rico.

• The Channel Islands Mammoth which lived on the prehistoric island of Santa Rosae in the California Channel Islands, and the small woolly mammoths of Saint Paul Island off Alaska, and Wrangel Island north of Siberia.
• Dwarf elephants in the recent natural history of Malta, Crete, Cyprus, and Sicily.^[2]
• Dwarf stegodons (elephant relatives) from the recent natural history of Flores, Sulawesi, Sumba and Timor.

^[3]

• A (disputed) species of hominin called Homo floresiensis, from fossils found on Flores Island in Indonesia.^[4]
• Small-Bodied humans from Palau, Micronesia, similar in size to the Flores hominins.^[5]

There are also proposed instances of this process occurring among plant life, the appearance of dwarf sequoia / redwood trees being one such proposal.^{[citation needed]}

This process, and other "island genetics" artifacts, can occur not only on traditional islands, but also in other situations where an ecosystem is isolated from external resources and breeding. This can include caves, desert oases, and isolated valleys.

There is an inverse form of this process, island gigantism, wherein small animals, lacking the predators of their normal homes, may become "gigantic" when breeding in isolation. An excellent example is the dodo, the ancestors of which were normal-sized pigeons. There are also several species of giant rats, some extinct and some still extant, that coexisted with both Homo floresiensis and the dwarf stegodons on Flores.

[edit] Additional examples

Carnivora

• Channel Island fox in California, United States, and the enigmatic, nearly extinct Cozumel fox
• Honshū Wolf in Japan
• Bali Tiger
• Cozumel Island Raccoon
• Sardinian Dhole
• Sardinian Lynx

Ungulates

• The strange, tiny Balearic Islands Cave Goat (Myotragus balearicus) in Majorca and Minorca and its close relative Nesogoral, from Sardinia which became extinct after human settlement
• Goats from the Juan Fernández Islands, in Chile
• Philippine water buffalo, Tamaraw, Anoa, the extinct Bubalus cebuensis and other dwarf bovids from South East Asia
• Several prehistoric species of dwarf hippopotamus from the Pleistocene of Mediterranean islands (such as Hippopotamus minor) and Madagascar
• Dwarf deer species on the Philippines (Philippine Sambar, extant), and Crete (Candiacervus ropalophorus), Ryukyu Islands of Japan (Cervus astylodon) and Gargano promontory of South Italy (Hoplitomeryx)(all extinct)
• Key Deer

Other

• The tiny flightless Inaccessible Island and Laysan Rails
• The dwarf nodosaurid Struthiosaurus from Europe, and the dwarf allosaur from South Australia

[edit] See also

Wikinews has related news: Bones of "small-bodied humans" found in cave

• Island gigantism
• Foster's rule
• Deep-sea gigantism
• Pleistocene extinctions
• Baron Franz Nopcsa

[edit] References

1. ^ Prothero, Donald R. & Sereno, Paul C. 1982 "Allometry and Paleoecology of Medial Miocene Dwarf Rhinoceroses from the Texas Gulf Coastal Plain" Paleobiology 8(1):16-30"
2. ^ Extinct dwarf elephants from the Mediterranean islands
3. ^ North American Extinctions v. World
4. ^ Scientist to study Hobbit morphing, abc.net.au
5. ^ Skull may identify tiny islanders who shrank to survive, The Independent

[edit] External links

• Strange world of island species October 31, 2004 The Observer

Retrieved from "http://en.wikipedia.org/wiki/Insular_dwarfism"

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“The People Time Forgot: Flores Find http://ngm.nationalgeographic.com/print/features/world/asia/georgia/flores-hominids-text

Diminutive human bones found in Flores, shown with stone tools and stegodont teeth.

At first we thought it was a child, perhaps three years old. But a closer look showed that the tiny, fragile bones we had just laid bare in a spacious cave on the Indonesian island of Flores belonged to a full-grown adult just over three feet tall.

Had we simply found a modern human stunted by disease or malnutrition? No. The bones looked primitive, and other remains from Liang Bua, which means "cool cave" in the local Manggarai language, showed that this skeleton wasn't unique. It was typical of a whole population of tiny beings who once lived on this remote island. We had discovered a new kind of human.

Back in the lab, where we analyzed the bones and other artifacts, the full dimensions of what we had discovered began to emerge. This tiny human relative, whom we nicknamed Hobbit, lived just 18,000 years ago, a time when modern humans—people like us—were on the march around the globe. Yet it looked more like a diminutive version of human ancestors a hundred times older, from the other end of Asia.

We had stumbled on a lost world: pygmy survivors from an earlier era, hanging on far from the main currents of human prehistory. Who were they? And what does this lost relative tell us about our evolutionary past?

A 220-mile-long (354 kilometer) island between mainland Asia and Australia, Flores was never connected by land bridges to either continent. Even at times of low sea level, island-hopping to Flores from mainland Asia involved sea crossings of up to 15 miles (24 kilometer). Before modern humans began ferrying animals such as monkeys, pigs, and dogs to the island about 4,000 years ago, the only land mammals to reach it were stegodonts (extinct elephant ancestors) and rodents—the former by swimming and the latter by hitching a ride on flotsam. No people could have reached Flores until modern humans came along, with the brainpower needed to build boats. Or so most scientists believed.

Yet in the 1950s and '60s Theodor Verhoeven, a priest and part-time archaeologist, had found signs of an early human presence. In the Soa Basin of Flores he found stone artifacts near stegodont fossils, thought to be around 750,000 years old. Homo erectus, an archaic hominin (a term for humans and their relatives), was known to have lived on nearby Java at least 1.5 million years ago, so Verhoeven concluded that erectus somehow crossed the sea to Flores.

As an amateur making extraordinary claims, Verhoeven failed to persuade the archaeological establishment. In the 1990s, however, other researchers used modern techniques to date tools from the Soa Basin to about 840,000 years ago. Verhoeven was right: Human ancestors had reached Flores long before modern humans landed. But no actual remains of Flores's earlier inhabitants had ever turned up.

So we went looking, focusing on Liang Bua, in the uplands of western Flores. By September 2003 our team of Indonesian and Australian researchers, assisted by 35 Manggarai workers, had dug 20 feet into the cave floor. Younger layers were rich in stone artifacts and animal bones, but by this point the dig seemed played out.

Then, a few days before the three-month excavation was due to end, our luck changed. A slice of bone was the first hint. The top of a skull appeared next, followed by the jaw, pelvis, and a set of leg bones still joined together—almost the entire skeleton of Hobbit.

Near the spot where archaeologists found the bones of Homo floresiensis, they unearthed flaked stone points among the remains of a stegodontr—an extinct relative of the elephant, which could weigh 800 pounds (400 kilograms). The points probably served as spearheads, indicating that these diminutive early ancestors were both sophisticated toolmakers and savvy hunters, says Mike Morwood, the Australian archaeologist who co-directed the dig on Flores with Radien Soejono of the Indonesian Centre for Archaeology. Since Homo floresiensis were about as small as modern three-year-olds, says Morwood, "hunting, butchering, and carrying dismembered carcasses of stegodonts back to their cave must have been a communal activity."

We knew we had made a stunning discovery, but we didn't dare remove the bones for a closer look. The waterlogged skeleton was as fragile as wet blotting paper, so we left it in place for three days to dry, applied a hardener, then excavated the remains in whole blocks of deposit.

Cradled in our laps, the skeleton accompanied us on the flight back to Jakarta, Indonesia's capital. There Peter Brown, a paleoanthropologist from the University of New England in Australia, supervised cleaning, conservation, and analysis. The pelvic structure told him Hobbit was a female, and her tooth wear confirmed that she was an adult. Her sloping forehead, arched browridges, and nutcracker jaw resembled those of Homo erectus, but her size was unique.

It wasn't just her small stature and estimated weight—about 55 pounds (25 kilograms)—but a startlingly small brain as well. Brown calculated its volume at less than a third of a modern human's. Hobbit had by far the smallest brain of any member of the genus Homo. It was small even for a chimpanzee.

The tiny skull is most reminiscent not of the hefty Homo erectus from elsewhere in East Asia but of older, smaller erectus fossils. Viewed from above, the skull is pinched in at the temples, a feature also seen in the 1.77-million-year-old Dmanisi people from Georgia, in western Asia. And in some respects, such as the shape of her lower jaw, the Liang Bua hominin harks back to even earlier fossils such as Lucy, the 3.2-million-year-old Australopithecus from Ethiopia.

And yet—strangest of all—she lived practically yesterday. Radiocarbon dating of charcoal pieces found next to the skeleton, together with luminescence dating that indicated when the surrounding sediments were last exposed to the sun, revealed her 18,000-year age. By mid-2004 our excavation at Liang Bua had yielded bones and teeth from at least six other individuals, from about 95,000 until as recently as 13,000 years ago.

For a few skeptics, all this is too much to swallow. They argue that the one complete skull must have come from a modern human with a rare condition called microcephaly, in which the brain is shrunken and the body dwarfed. The other small bones, they say, might be the remains of children. But last year's discoveries include part of a second adult skull—a lower jaw—that is just as small as the first. It simply strains credibility to invoke a rare disease a second time.

Instead, Hobbit is our first glimpse of an entirely new human species: Homo floresiensis. Her kind probably evolved from an earlier Homo erectus population, likely the makers of the tools Verhoeven found. Her ancestors may have stood several feet taller at first. But over hundreds of thousands of years of isolation on Flores, they dwindled in size.

Such dwarfing is often the fate of large mammals marooned on islands. There they generally face fewer predators—on Flores, Komodo dragons were the only threat—which makes size and strength less important. And the scarce food resources on a small island turn a large, calorie-hungry body into a liability. On mainland Asia, stegodonts sometimes grew bigger than African elephants; at Liang Bua they were only a bit bigger than present-day water buffalo.

Researcher Kira Westaway uses a drill to remove a core sample from a stalagmite taken from a cave near Liang Bua. Stalagmites form when rain seeps through rock crevices above a cave and drips onto the floor, where minerals in the water pile up to form calcified mounds. By dating the stalagmite and analyzing its oxygen and carbon composition, Westaway and other scientists working on Flores hope to find clues to the climate and vegetation of the site when Homo floresiensis lived there.

In the past some anthropologists have argued that even in prehistory humans could adapt to new environments by inventing new tools or behaviors rather than by physically evolving, like other creatures. The dwarfing seen on Flores is powerful evidence that humans aren't exempt from natural selection. The discovery of Hobbit is also a hint that still other human variants may once have inhabited remote corners of the world.

In spite of their downsized brains, the little people apparently had sophisticated technology. The fireplaces, charred bones, and thousands of stone tools we found among their remains must have been their handiwork, for we found no sign of modern humans. Stone points, probably once hafted onto spears, turned up among stegodont bones, some of which bore cut marks. The little hominins were apparently hunting the biggest animals around. It was surely a group activity—adult stegodonts, although dwarfed, still weighed more than 800 pounds (363 kilograms), formidable prey for hunters the size of preschool children.

The discovery underscores a puzzle going back to Theodor Verhoeven: How could ancient hominins ever have reached Flores? Was Homo erectus a better mariner than anyone suspected, able to build rafts and plan voyages? And it raises a new and haunting question. Modern humans colonized Australia from mainland Asia about 50,000 years ago, populating Indonesia on their way. Did they and the hobbits ever meet?

There's no sign of modern humans at Liang Bua before 11,000 years ago, following a large volcanic eruption that would have wiped out any Homo floresiensis in the region. But other bands may have hung on elsewhere in Flores. Perhaps modern humans did meet their ancient neighbors before something—maybe a changing environment, maybe competition or conflict with modern humans themselves—spelled the end for the little people. Further excavations on Flores, and on nearby islands that might have had their own hobbits, may settle the question.

In the meantime a clue may come from local folktales about half-size, hairy people with flat foreheads—stories the islanders tell even today. It's breathtaking to think that modern humans may still have a folk memory of sharing the planet with another species of human, like us but unfathomably different.

The Australian Research Council supported this work; your Society will help sponsor future study.

Could this be the face—shown life-size—of a lost human species that stood three feet tall and inhabited an isolated island world?

Synthetic skin and hair bring to life the cast of an 18,000-year-old skull of a female. Her remains were found with those of six other tiny beings on Flores, where they hunted creatures from giant rats to Komodo dragons and made stone tools—all with brains smaller than a chimp's.

Miniature beings with skulls far smaller than our own sprang from an ancient line of human ancestors. How did they reach—and survive on—a remote Indonesian island?

Thomas Sutikna of the Indonesian Centre for Archaeology holds a skull that he and fellow scientists believe represents a new human species, Homo floresiensis. Found in a cave on Flores (map), the species existed alongside modern humans as recently as 13,000 years ago, yet may descend from Homo erectus, which arose some two million years ago.

No ancient humans could have reached flores before big-brained modern people—or so it seemed.

The first itinerant humans, Homo erectus, crossed land bridges from Asia to Indonesia. But their trail seemed to end at Java (above), the site of Homo erectus bones at least 1.5 million years old. No one believed these early humans could cross the ocean barrier called Wallace's line. Scientists thought it wasn't until 50,000 years ago that people—modern Homo sapiens—made the jump. But 840,000-year-old stone tools found in the Soa Basin on Flores are a sign that Homo erectus crossed Wallace's line much earlier. "How they managed to get there is still a real mystery," says Mike Morwood of the University of New England in Australia.

Looking for signs of early humans, archaeologists Wahyu Saptomo and Mike Morwood (below) examine stone artifacts found buried in a limestone cave that the local Manggarai people call Liang Bua. Above its massiveentrance (above right) gray stalactites hang like jagged fangs, but the grim exterior belies an inner beauty. "It's very much like a cathedral inside," says Morwood, who has excavated here since 2001. He says islanders have used the cave as a burial ground for millennia. The dirt below its clay floor is riddled with human bones from a range of eras. But Morwood is interested in the cave's first occupants, Homo floresiensis, who arrived at least 95,000 years ago. The search has involved hauling tons of dirt bucket by bucket to a washing station set up in a nearby rice field (above left), where researchers sifted artifacts and bones from the mud. The work paid off with the discovery of remains from at least seven tiny individuals. The team also found well-flaked stone points—possibly spearheads—that suggest Homo floresiensis, although much smaller than its Homo erectus ancestors, was also smarter.

For millennia the only land mammals on flores were rodents, stegodonts, and humans.

The Homo floresiensis skeleton stands roughly half as tall as a modern adult's. "I knew within about 60 seconds of seeing the jawbone that this was something entirely new," says paleoanthropologist Peter Brown, who examined the bones. The premolars are a giveaway, with a root much different from ours. The pelvis of this female is also wider than in Homo sapiens. Her arms hung almost to her knees, says Brown, but her delicate hand and wrist bones imply that "she wasn't doing a lot of climbing."

Why were the Flores humans so small? Biogeographer Mark Lomolino, who studies the phenomenon called island dwarfism, says, "We know that when evolutionary pressures change, some species respond by shrinking." Stegodonts—extinct elephant ancestors—were especially prone to dwarfing, because they often colonized islands. "Elephants are strong swimmers," he says. Once there, with limited food and fewer predators, they shrank. On Sicily, Crete, and Malta, scientists have unearthed bones from primitive elephants as little as a twentieth the size of mainland forms. But other species, such as rats, tend to grow larger in a place without competitors. Flores yielded remains of giant rats and lizards, as well as cow-size dwarf stegodonts and diminutive human bones (shown above with stone tools and stegodont teeth). Peter Brown says the tiny Homo floresiensis may have evolved from a population of Homo erectus that reached Flores some 800,000 years ago. "The problem is we haven't found Homo erectus bones," says Brown. "All we have is these small-bodied people." “

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Homo floresiensis http://australianmuseum.net.au/Homo-floresiensis

One of the most controversial and surprising hominin finds in a century, conflicting interpretations and debates surround the remains of these tiny humans from Indonesia. H. floresiensis are not our ancestors but their unusual features and recent survival suggests our human family tree is more complex than once thought.

Background of discoveries

Age

The human remains date from about 38,000 to 18,000 years old, but archaeological evidence suggests H. floresiensis lived at Liang Bua from at least 95,000 to 13,000 years ago. These dates make it the latest-surviving human apart from our species H. sapiens.

Their disappearance, along with that of other local fauna, is suggested as being due to a volcanic eruption that occurred on Flores approximately 12,000 years ago. A layer of ash dating to this time exists in the Liang Bua cave. It is also possible that the arrival of modern humans played a role, but there is no evidence of them in Liang Bua cave until 11,000 years ago. Climate change has also been suggested, but there is no evidence for this.

Important discoveries

A joint Australian-Indonesian team, looking for evidence of the early migration of Homo sapiens from Asia to Australia, stumbled on the remains of a small human in the cave of Liang Bua, Flores, in 2003. The discoverers (Peter Brown, Michael Morwood and colleagues) argued that a variety of primitive and derived features identified the remains as that of a new species. Descriptions of some of the remains and the new species designation were published in October 2004.

The remains include a largely complete skeleton with skull (LB1) and parts of at least eleven other individuals. These remains come from different levels and range in date from 38,000 to 13,000 years old. An arm bone, from a deeper level and dating to about 74,000 years old, is provisionally assigned to H. floresiensis. A more accurate designation is difficult to make as LB1 lacks an arm bone to make comparisons with.

Stone tools have been recovered from a number of levels and range in dates from 94,000 to 13,000 years old.

As the remains are relatively young and unfossilised, researchers hoped to find mitochondrial DNA. Initial efforts were unsuccessful, but the research continues.

Key specimens

• LB1 – type specimen discovered in September 2003. It is unfossilised and dates to 18,000 years old. The remains consist of a fairly complete skull and partial skeleton including leg bones, parts of the pelvis, hands and feet, and some other fragments. It is assumed to belong to a female aged about 30 years old. She stood about 1 metre tall, had a brain volume of about 380-420cc and weighed about 25 kilograms. The body was not deliberately buried but covered soon after death by fine sediments, when still partially fleshed.
• LB6 – a partial skeleton belonging to a shorter individual than LB1. It has a more V-shaped jaw and is assumed to be a child, possibly only 5 years old.

What the name means

The genus name Homo is the Latin word for ‘human’ or ‘man’. The species name floresiensis recognises the island of Flores in Indonesia where the remains were found.

They are commonly referred to as the ‘hobbits’, after the Lord of the Rings characters, in reference to their small size and large feet.

Distribution

All remains come from the cave of Liang Bua on the island of Flores in Indonesia. Flores lies towards the eastern end of the Indonesian island chain.

Flores has always been separated from mainland Asia - even at low sea levels the water-crossing was at least 24 kilometres. It is known that other animals reached Flores by swimming or floating on debris. How or when H. floresiensis reached the island is unknown.

Relationships with other species

Ancestry

When first discovered, it was suggested that H. floresiensis was possibly descended from Javanese H. erectus. However, more detailed analysis of skeletal remains has uncovered traits more archaic than Asian H. erectus and more similar to australopithecines, H. habilis or the hominins from Dmanisi in Georgia (classified as Homo ergaster or Homo georgicus). Most scientists that accept H. floresiensis as a legitimate species now think its ancestor may have come from an early African dispersal and have been similar in appearance to H. habilis or the Dmanisi hominins. This means that it shared a common ancestor with Asian H. erectus but was not descended from it.

Unfortunately, no transitional forms, or the actual remains of H. erectus itself, have been found in Flores. However, stone tools that may have been made by H. erectus (or a similar species) were discovered on Flores. These date to 840,000 years ago, so indicate that a hominin species was probably living on the island at that time.

Whatever the origins of the ancestral population, it is accepted that the population underwent long term isolation on the island which resulted in an endemic dwarf species H. floresiensis. This is a common phenomenon seen in other mammals in similar environments.

Contemporaries

Modern humans arrived in Indonesia between 55,000 and 35,000 years ago, and may have interacted with H. floresiensis, although there is no evidence of this at Liang Bua.

Interestingly, local legends exist in Flores of the Ebu Gogo – small, hairy, cave dwellers similar in size to H. floresiensis. It is suggested that perhaps the hobbits survived longer in other parts of Flores to become the source of these stories.

A new species or a small Homo sapiens?

Doubts that the remains should be classified as a new species are voiced by a number of scientists, some vehemently. They claim that the remains come from a modern human with some sort of physical disorder. The alternate suggestions include:

• the remains are from a very small human that suffered from some type of disease that causes microcephaly, a developmental disorder of the brain that causes it to be much smaller than normal
• the remains are from a human with Laron syndrome, a disorder that results in pituitary dwarfism (published in 2007 by a team from Tel Aviv University, Israel)
• the remains are those of dwarfed Homo sapiens similar to the small-bodied humans that inhabited the Micronesian island of Palau between 1400 and 3000 years ago. These people shared some features with the H. floresiensis specimens, but not all. Detailed analysis of the Palau specimens is unlikely to settle arguments over the status of H. floresiensis but they do suggest that some of its unusual features could be due to environment rather than ancestry.

Many of those rejecting the new species status focus only on the remains of LB1, and ignore the other remains that show many of the same characteristic features. In contrast, a number of recent analyses of the skull, face, foot and wrist have confirmed the many unusual primitive features of H. floresiensis remains and stated that they are more similar to australopithecines. For instance:

• a cladistic analysis done in 2009 supported H. floresiensis as a separate species (Journal of Human Evolution Online as of 4 August 2009)
• a study using 3D-morphometrics showed that the skull of LB1 differs significantly from all H. sapiens skulls, including those of small-bodied individuals and microcephalics, and is more similar to the skull of Asian Homo erectus (Baab & McNulty, Journal of Human Evolution, 2008)
• a team of experts created detailed maps of imprints left on LB1’s braincase and concluded that the remains belonged to a new species. Comparisons of different parts of the brain showed it was nothing like a microcephalic's and is also different from modern humans. The endocasts also revealed that parts of the frontal lobe and other features were consistent with higher cognitive processes. (Falk et al, PNAS, January 29, 2007,)
• H. floresiensis wrist is almost indistinguishable from an African ape or early hominin wrist and is nothing like those of modern humans or Neandertals. The distinctive shapes of wrist bones form during pregnancy and as most pathologies and growth disorders affect the skeleton well after that, this demonstrates that the remains come from a new Homo species. (Matt Tocheri et al, Science 21 September 2007)
• studies on brain-size reduction in dwarf hippos from Madagascar revealed that brains shrank to volumes well below predicted sizes. This refutes a key argument used by sceptics who claim the brains are too small for dwarfing alone to be the cause (hence they cite microcephaly or similar disorders), (Weston & Lister, Nature, 7 May 2009)

Key physical features

Body size and shape

• very small stature of about 1 metre (the remains of 5 individuals were used for this average), which is less than the average for short populations of humans such as pygmies (who average about 1.4-1.5 m tall)
• the wide pelvis and hunched shoulders give it a different body shape compared with H. sapiens

Brain

• combination of features not seen in other hominin species
• has features that are not found in H. sapiens, particularly in the temporal and frontal lobes
• small brains averaging 380cc, about the size of a chimpanzee. This suggests there was active selection for a small brain size, possibly related to the reduced energy requirements of small brains.

Skull

• cranial shape is long and low and closer to that of H. erectus than H. sapiens
• receding and small forehead
• thick bones within the range of H. erectus and H. sapiens
• flat face
• brow ridges over each eye that do not form a continuous brow ridge as in Indonesian H. erectus

Jaws and teeth

• lacks the bony point on the chin found in modern humans
• relatively large jaw and teeth that resemble H. erectus but with more primitive features
• premolar roots different from H. sapiens
• small post-canine and canine teeth
• parabolic or V-shaped dental arcade typical of Homo
• bony shelf at the front of the lower jaw which is a primitive feature not seen in H. erectus

Limbs and pelvis

• bones and joints of the arm, shoulder and the lower limbs suggest that H. floresiensis was more similar to early humans than modern humans
• characteristic bipedal foot that includes a big toe aligned with other toes and a locking mechanism on the middle of the foot to help stiffen the arch after heel lift occurs
• several primitive features include a relatively long foot for its body size, a flat arch lacking the spring-like mechanism used to store and release energy during running, and a short big toe. These features are similar to ancient hominins such as H. habilis (OH8) and australopithecines
• features in the foot suggest the gait was different from and less efficient than modern humans
• unusual low twist in the upper arm bone
• wide leg bones compared to the length
• relatively short and curved clavicle
• shape of the shoulder blade resulted in the shoulder being moved forwards slightly as if hunched
• wrist bones differ significantly from the those of modern humans and are more similar to African apes or australopithecines. They lack features that evolved with the ancestors of modern humans at least about 800,000 years ago
• primitive flared ilium blades in the pelvis, and females have wider pelvises than H. sapiens females
• relatively long arms

Lifestyle

Culture

Tools

Stone tools were found in a number of different layers dating from 90,000 to 13,000 years ago. Tools include simple flakes, points, perforators, blades and microblades which were possibly hafted as barbs. Some were found with the remains of LB1, but most came from the same location as the remains of the extinct pygmy elephant Stegodon. This suggests that H. floresiensis was hunting these small elephants. Stone tools produced by heavier percussion were also recovered from layers not associated with H. floresiensis occupation. These tools date to about 102,000 years ago. The makers are unidentified.

There has been some speculation that the stone tools associated with H. floresiensis were actually made by H. sapiens. The basis for this is purely the belief that humans with such small brains couldn’t make such sophisticated stone tools – there is no other evidence in support of this. However, those studying the tools claim they are not as sophisticated as they appear and regard them as ‘simple’.

Analysis of the residues and polish on some of the tools revealed they were used for working wood and fibrous materials, perhaps to make spear shafts or items such as traps. Cut marks on the Stegodon bones also suggest some of the tools were used to process meat.

Precursors to this tool kit may come from earlier sites on Flores. Tools excavated from Mata Menge (about 50km from Liang Bua) in 2004-5 are at least 700,000 years old, and those from the Soa Basin date to about 880,000 years old. Tool kits from both sites show some similarities and technological continuity with those found in Liang Bua cave. The identity of the makers is unknown.

Fire

There is evidence of the use of fire in Liang Bua cave. The remains of numerous juvenile Stegodon have charred bones, possibly indicating that H. floresiensis was able to control fire for cooking.

Other

There are no traces of pigments, ornaments or deliberate burials in the layers associated with H. floresiensis – all of which characterise the modern human levels from the upper parts of the cave.

Environment and diet

Flores is a heavily forested tropical island with mountain peaks reaching over 2000 metres. The environment during H. floresiensis time would have been similar. The nature of their environment and the limited food sources typical of such islands provides strong clues to the evolution of H. floresiensis. When a small population becomes separated, changes can occur very quickly. This particular environment favours reduced energy requirements with dwarfing a response to this. Several dwarf species, including Stegodon, have been recovered on Flores and other small islands.

This species shared the island with pygmy elephants Stegodon, giant rats and large lizards like Komodo dragons. Evidence of cut marks on the Stegodon bones from Liang Bua cave show that H. floresiensis was at least hunting and eating this animal.

Fran Dorey , Exhibition Project Coordinator
Last Updated: 11 November 2009

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Latest Word: Prehistoric Hobbits were not Victims of a growth Disorder - April 28th, 2008

Scientists at Florida State University in Tallahassee say that remains of Homo floresiensis, also known as hobbits, do not show any sign of growth disorders, refuting earlier claims that hobbits were pygmy Homo sapiens that suffered from a growth disorder.

Lead researcher Dean Falk and her Florida State colleague Angela Schauber came to this conclusion after studying computer-generated reconstructions of the fossilized skulls of the small islanders. They suspect that Homo floresiensis especially as represented by a partial skeleton called LB1adapted to a challenging island environment by evolving into a smaller but proportionally equivalent version of an ancestral species, possibly Homo erectus.

LB1 didn't have any of the growth pathologies that have been attributed to it, Falk said.

A study unveiled last year suggested that LB1 exhibits 33 skeletal symptoms of Laron Syndrome, a type of insensitivity to growth hormones. Besides a reduction of face and limb size, this condition includes a round protrusion of the forehead and a depressed ridge on top of the nose. Falk, however, says that measurements, photos, and 3-D computer tomography reconstructions of LB1 do not show any similarity to published data on the anatomy of Laron Syndrome.

She says that LB1 displays unique skull and tooth traits. She says that it also possesses whopping long feet relative to body size, in contrast to the typically small feet observed in Laron Syndrome. Apart from this, preliminary findings also show that LB1 did not suffer from one form of microcephaly, a genetic growth disorder, or from cretinism, a nutritionally influenced growth disorder.

Schauber used museum skeletal collections to establish that certain species of foxes and mice have evolved into proportional miniatures of larger counterparts. The same process could apply to Homo floresiensis, she says. She says that island gray foxes, found on islands off the California coast, show the same brain size relative to body size as larger mainland foxes do. The research also showed that dwarf little mice matched the relative brain size of much larger, normal-sized mice, she adds.

Schauber says that LB1 shows no signs of having had a relative brain size distorted by any growth disorder, and could well have been a proportional dwarf, as observed in foxes and mice. Robert Eckhardt of Pennsylvania State University in University Park, however, still regards LB1 as a pygmy Homo sapiens that suffered from a still-undetermined growth disorder.

About 400 dwarfing syndromes exist in people today, leaving an extensive list for Falk and her fellow hobbit advocates to consider for LB1, Eckhardt said at the annual meeting of the American Association of Physical Anthropologists, where Falk and Schauber presented separate papers. Primitive-looking features of LB1s wrist and arms actually fall within the range of variation for people today, Eckhardt argued. Homo floresiensis is an imaginative composite, he concluded. (ANI)

From Afarensis, Anthropology, Evolution and Science

Homo floresiensis: Walk Like a Clown?

Tolkien's hobbits walked an awful long way, but the real "hobbit", Homo floresiensis, would not have got far. Its flat, clown-like feet probably limited its speed to what we would consider a stroll, and kept its travels short, says Bill Jungers, an anthropologist at the State University of New York in Stony Brook. "It's never going to win the 100-yard dash, and it's never going to win the marathon," he says. He presented his conclusion at last week's meeting of the American Association of Physical Anthropologists in Columbus, Ohio.

By analysing the nearly complete left foot of an 18,000-year-old hobbit skeleton dubbed LB1, found on the Indonesian island of Flores , Jungers' team estimated the length of the hobbit's feet, which were unusually large for its meter-high frame. "Sort of like a young girl wearing her mum's shoes," Junger says.

And because of their long feet, Homo floresiensis probably had to bend its knee further back than modern humans do, resulting in a sort of high-stepped gait. "You would watch these hobbits walk and say they're walking a little funny," Jungers says. The foot had other peculiar features as well. For one, its big toe was quite short compared with the others, similar to earlier hominids such as Australopithecus. However, the shape of the toes, even the short big toe, is like modern human ones, Jungers says. "It has a human morphology and an ape-like proportion," he says. Jungers and other researchers who claim the hobbit was a distinct species from Homo sapiens point to the foot as further evidence supporting their theory. It has been suggested that the hobbit suffered from a severe block to growth known as cretinism or a disease called microcephaly that leads to miniaturized heads. "It puts another nail in the coffin of the disease hypothesis," says Henry McHenry, an anthropologist at the University of California, Davis who saw the presentation. But the feet don't solve the bigger mystery of where Homo floresiensis originated, McHenry says. "It's so strange," he muses.

Hopeful, they had a podiatrist in their health plan as well!

From New Scientist, # 12:30 16 April 2008 # NewScientist.com news service # Ewen Callaway

Were the Hobbits Cretins?

As reported by ScienceNow, a new study conducted by Peter Obendorf and Benjamin Kefford of the RMIT University of Melbourne and Charles Oxnard of the University of Western Australia at Crawley concluded that the small stature of the Homo floresiensis was not the result of genetic defects. The study, published in the journal Proceedings of the Royal Society B, suggests that the hobbits' size was caused by a condition known as cretinism. This is due to a lack of iodine. Comparing the pituitary flossa in a hobbit skull with individuals suffering from cretinism, they found a significant match and thus suggested a new theory. The remains of twelve hobbits were originally found in a cave in Liang Bua. Obendorf stated that it is an area where people still suffer from goiters that results from iodine deficiency. The new study even mentions that local myths include stories of tiny people who lived in caves. While it may be too early to discard the microcephaly hypothesis altogether, the case for hobbits being real humans is much stronger than before. We should probably do well to forget the image of an ape-like man carrying a furry animal on his shoulder and start describing hobbits as real people. It seems that the distinction between hobbits and humans is found only in Tolkien's Midde-Earth but not on this earth.

Sarah would not be amused with these cretins!

Ancient Bones of Small Humans Discovered in Palau

Thousands of human bones belonging to numerous individuals have been discovered in the Pacific island nation of Palau. Some of the bones are ancient and indicate inhabitants of particularly small size, scientists announced today. The remains are between 900 and 2,900 years old and align with Homo sapiens, according to a paper on the discovery. However, the older bones are tiny and exhibit several traits considered primitive, or archaic, for the human lineage. "They weren't very typical, very small in fact," said Lee Berger, a paleoanthropologist at the University of Witwatersrand in Johannesburg, South Africa. Berger was on vacation in 2006, kayaking around rocky islands about 370 miles (600 kilometers) east of the Philippines, when he found the bones in a pair of caves. The caves were littered with bones that had been dislodged by waves and piled like driftwood. Others had remained buried deep in the sandy floor, and more, including several skulls, were cemented to the cave walls. Berger returned later that year with colleagues to excavate some of the remains with funding from the National Geographic Society. (National Geographic News is a division of the National Geographic Society.) A paper to appear tomorrow in the Public Library of Science journal PLoS ONE describes the findings and what they suggest about small-bodied humans. Interpreting the Bones Two sets of human bones were found in the Palauan caves. The most recent remains were found near the entrance to one of the caves and appear normal in size. Older bones found deeper in the caves are stranger and much smaller. The smaller, older bones represent people who were 3 to 4 feet (94 to 120 centimeters) tall and weighed between 70 and 90 pounds (32 and 41 kilograms), according to the paper.

The diminutive people were similar in size to the so-called hobbit discovered in National Geographic Society-supported excavations on the Indonesian island of Flores in 2003. Scientists classified the hobbit as a separate human species, Homo floresiensis. According to Berger, the estimated brain size of the early Palauans is about twice the size of the hobbit brain. Several other features, including the shape of the face and hips, suggest that the Palauan bones should be classified as Homo sapiens. If the interpretation of the Palauan remains is correct, the find may add more fuel to the debate over whether the Flores hobbit is a unique species, Berger said. Aside from being tiny, the Palauan bones show that some of these people lacked chins and had deep jaws, large teeth, and small eye sockets, according to the paper. Some of these features were considered important in originally distinguishing the hobbit as a unique—and archaic—species, Berger said. But the Palauan remains suggest these features may just be a consequence of insular dwarfism, a shrinking process that some scientists attribute to the stresses of a small island environment.

Palau lacks indigenous terrestrial mammals and large reptiles that early Palauans might have used for food. Archaeological records indicate fishing was not a local activity until about 1,700 years ago, around the time bigger bones appear in the caves. The early Palauans' limited diet, combined with a tropical climate, absence of predators, a small founding population, and genetic isolation, may have produced "these very odd features and very small body size," Berger said.

The Controversy

William Jungers, an anthropologist at Stony Brook University in New York and a former National Geographic grantee, stands by his conclusion that the hobbit is a unique species. He notes that the small bones, large teeth, lack of a chin, and other features that characterize the early Palauans as well as the hobbits can be found in other small-bodied human populations around the world. But "the smallest-bodied people on Earth do not converge on the proportions and various aspects of morphology of the hobbits," Jungers said. Jungers points out that the hobbit is distinguished from modern humans by jaw structures called transverse tori, which are seen in human ancestors, such as australopithecines and some Homo erectus fossils, he noted. Chris Stringer, lead researcher in the human-origins program at London's Natural History Museum, points to other defining characteristics in the hobbits' feet, teeth, and shoulder and wrist bones. Based on this evidence, he says, "I still believe that the Flores material is something distinct and primitive."

Berger says his team has yet to analyze the shoulder, feet, and wrist bones in their Palauan sample and thus cannot comment on how they compare to the hobbit bones. A Disease Factor? Unlike the Palauan bones, the hobbit fossils include a skull with an exceptionally small braincase. Its volume is much smaller than that of small-bodied peoples living today on other Pacific islands and in the forests of Africa. It is also smaller than that of the early Palauans. Some scientists argue that the unusually small brain volume of the hobbit makes it not a unique species but rather a small-bodied Homo sapiens with microcephaly, a genetic disease that causes small brains and other abnormalities. A team of researchers from Australia recently reported that the unusual limbs of Homo floresiensis may also have been influenced by disease. The distortions, they claim, are sometimes seen in the offspring of a normal, small-bodied human female with goiter. Berger says his team's findings might support these disease arguments. But they have yet to find an individual in their sample who had one of these diseases and therefore can't make a comparison.

The Debate Continues Dean Falk is an anthropologist at Florida State University in Tallahassee who received National Geographic funding to compare the Flores skull with both microcephalics and modern humans without disease. She and colleagues from the Mallinckrodt Institute of Radiology concluded in a study published last year that the hobbit was not microcephalic. Falk said the finding closed the microcephaly argument. The Palauan remains, she added, are just a set of small bones, representing small-bodied people. ""But being small does not make one comparable to Homo floresiensis," she noted. "It makes one small—period."

Steven Churchill, a paleontologist at Duke University and co-author of the new study, says the Palauan discovery expands the known range of variation in modern humans in Southeast Asia, adding context in which to interpret the hobbit fossils. Several scientists, he adds, continue to believe "there's something wrong with Flores." One of these scientists is Robert Martin, the curator of biological anthropology at the Field Museum in Chicago, Illinois. He says it's well known that small-bodied human populations exist in Southeast Asia. A community of pygmies now lives near the Flores hobbit site in the village of Rampapasa, so finding small-bodied Homo sapiens on Palau, he says, "is no surprise." From Martin's perspective, the problem with the classification of the hobbit as a separate species is that it is based largely on the brain size of "one microcephalic individual in Flores. … Body size is really a separate issue." According to Berger, the new findings suggest that "you don't have to look very far to find the facial and dental characters thought to be unique in Flores." If traits such as those found among the early Palauans are common on islands, he said, then scientists who want to name a new species in the human lineage will have to present "a much better case built on a lot more fossils before the world will buy it." ----------- news.nationalgeographic.com

Homo floresiensis: More Microcephaly Claims

According to New Scientist a new study will be published in Science indicating that Homo floresiensis was a microcephalic member of a dwarfed population (splitting the difference I guess). The study modeled dwarfism in a range of mammals:

"As they dwarf, species' brain sizes decline far more slowly than body size," says Ann MacLarnon from Roehampton University, UK, who modeled dwarfing in a range of mammals from dogs to elephants with a team from the Field Museum, Chicago, US. "Brain size is key to a mammal species' identity," she says. There is, for example, hardly any difference in brain size between the smallest modern humans, the 1.4-metre Bambuti people of Congo's Ituri Forest, and the tallest, the 2-metre Masai of east Africa. The team calculated that a dwarfed Homo erectus with a 400cc brain would weigh just 2 kilograms. "That's one-tenth of what the Flores people must have weighed," she explains. The only way to explain the discrepancy, the team believes, is microcephaly.

Morwood disputes this:

"Although we only have one cranium," says Morwood, "the other bones we found show that LB1 was a normal member of an endemically dwarfed hominid population." The distinctive traits of reduced body mass, reduced brain size and short thick legs mirror those found in other island endemic populations of large mammals, Morwood says. He calls the microcephaly explanation "bizarre". It ignores other evidence from Liang Bua and the literature on island endemic evolution, he says.

MSNBC also has an article on it:

In a response to their paper, researchers led by Dean Falk of Florida State University called Martin's assertions "unsubstantiated." Martin's comparison of LB1 with the skulls of microcephalics lacks crucial details, Falk stated. Falk also challenged Martin's comment that such a small brain size would indicate an extremely tiny creature based on the calculations for dwarf versions of other animals. It would be surprising if the dwarf version of an early human scaled down in the same way as an elephant, for example, Falk responded. Falk and his co-authors argued that the size of LB1's brain is consistent with that of adult microencephalics.

Weird, first Falk is qouted as dismissing the microcephaly argument then supporting it, I think the reporter was confused...

National Geographic has more:

The disease has dozens of different forms, Martin says. But Falk and colleagues only compare the Flores fossil to one poorly matched microcephalic skull of a modern human.
Martin's team, by contrast, identified other microcephalic skulls that more closely resemble the Flores fossil skulls, he says. Falk acknowledges that her team only examined one skull. But she adds that the evidence that Martin's team's skulls are better matched is poorly illustrated in Martin's paper. Regardless, Falk adds, her team is finishing up an in-depth analysis on microcephaly. "We're confident that [the hobbit skull] is not a microcephalic," she said.

Also, Falk and her colleagues noted in their original paper that normal dwarfing of Homo erectus could not explain the Flores fossils. Rather, they suggested the hobbits resulted from dwarfing of apes or australopithecines, earlier human ancestors.

Potts says Martin and colleagues are primarily reacting to the original interpretation of the hobbit find, published in 2004 in the journal Nature. That study said that the Flores fossils represent island dwarfing in Homo erectus and not dwarfing of an ape or australopithecine.

"So what would island dwarfing in an ape look like?" Potts asked. "We don't know--that's one of the big gaps of this whole thing."

In addition, Potts says, Martin and colleagues' suggestion that the Flores skull represents a microcephalic modern human is unsupported by recent studies on leg and shoulder fossils from Flores that suggest similarities to earlier human ancestors.

"We're dealing with something unprecedented in modern humans," Potts said.

"[The hobbit is] either a representative of a unique and unreported range of variation in a modern human, or it's a new species that seems to be derived from an earlier ancestor. "That second idea is more in line with the original interpretation and probably the safest at this stage," he continued. "But it's a wonderful mystery."

http://scienceblogs.com/afarensis/2006/05/18/homo_floresiensis_more_on_micr/

Posted on: May 18, 2006 3:57 PM, by afarensis, FCD

A skull that rewrites the history of man

It has long been agreed that Africa was the sole cradle of human evolution. Then these bones were found in Georgia...

By Steve Connor, Science Editor

Wednesday, 9 September 2009

One of the skulls discovered in Georgia, which are believed to date back 1.8 million years

• enlarge

The conventional view of human evolution and how early man colonised the world has been thrown into doubt by a series of stunning palaeontological discoveries suggesting that Africa was not the sole cradle of humankind. Scientists have found a handful of ancient human skulls at an archaeological site two hours from the Georgian capital, Tbilisi, that suggest a Eurasian chapter in the long evolutionary story of man.

The skulls, jawbones and fragments of limb bones suggest that our ancient human ancestors migrated out of Africa far earlier than previously thought and spent a long evolutionary interlude in Eurasia – before moving back into Africa to complete the story of man.

Experts believe fossilised bones unearthed at the medieval village of Dmanisi in the foothills of the Caucuses, and dated to about 1.8 million years ago, are the oldest indisputable remains of humans discovered outside of Africa.

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• Steve Connor: Out of Africa... and back again? The story of humans unravels

But what has really excited the researchers is the discovery that these early humans (or "hominins") are far more primitive-looking than the Homo erectus humans that were, until now, believed to be the first people to migrate out of Africa about 1 million years ago.

The Dmanisi people had brains that were about 40 per cent smaller than those of Homo erectus and they were much shorter in stature than classical H. erectus skeletons, according to Professor David Lordkipanidze, general director of the Georgia National Museum. "Before our findings, the prevailing view was that humans came out of Africa almost 1 million years ago, that they already had sophisticated stone tools, and that their body anatomy was quite advanced in terms of brain capacity and limb proportions. But what we are finding is quite different," Professor Lordkipanidze said.

"The Dmanisi hominins are the earliest representatives of our own genus – Homo – outside Africa, and they represent the most primitive population of the species Homo erectus to date. They might be ancestral to all later Homo erectus populations, which would suggest a Eurasian origin of Homo erectus."

Speaking at the British Science Festival in Guildford, where he gave the British Council lecture, Professor Lordkipanidze raised the prospect that Homo erectus may have evolved in Eurasia from the more primitive-looking Dmanisi population and then migrated back to Africa to eventually give rise to our own species, Homo sapiens – modern man.

"The question is whether Homo erectus originated in Africa or Eurasia, and if in Eurasia, did we have vice-versa migration? This idea looked very stupid a few years ago, but today it seems not so stupid," he told the festival.

The scientists have discovered a total of five skulls and a solitary jawbone. It is clear that they had relatively small brains, almost a third of the size of modern humans. "They are quite small. Their lower limbs are very human and their upper limbs are still quite archaic and they had very primitive stone tools," Professor Lordkipanidze said. "Their brain capacity is about 600 cubic centimetres. The prevailing view before this discovery was that the humans who first left Africa had a brain size of about 1,000 cubic centimetres."

The only human fossil to predate the Dmanisi specimens are of an archaic species Homo habilis, or "handy man", found only in Africa, which used simple stone tools and lived between about 2.5 million and 1.6 million years ago.

"I'd have to say, if we'd found the Dmanisi fossils 40 years ago, they would have been classified as Homo habilis because of the small brain size. Their brow ridges are not as thick as classical Homo erectus, but their teeth are more H. erectus like," Professor Lordkipanidze said. "All these finds show that the ancestors of these people were much more primitive than we thought. I don't think that we were so lucky as to have found the first travellers out of Africa. Georgia is the cradle of the first Europeans, I would say," he told the meeting.

"What we learnt from the Dmanisi fossils is that they are quite small – between 1.44 metres to 1.5 metres tall. What is interesting is that their lower limbs, their tibia bones, are very human-like so it seems they were very good runners," he said.

He added: "In regards to the question of which came first, enlarged brain size or bipedalism, maybe indirectly this information calls us to think that body anatomy was more important than brain size. While the Dmanisi people were almost modern in their body proportions, and were highly efficient walkers and runners, their arms moved in a different way, and their brains were tiny compared to ours.

"Nevertheless, they were sophisticated tool makers with high social and cognitive skills," he told the science festival, which is run by the British Science Association.

One of the five skulls is of a person who lost all his or her teeth during their lifetime but had still survived for many years despite being completely toothless. This suggests some kind of social organisation based on mutual care, Professor Lordkipanidze said.

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· 5 things forensic anthropolgists try to determine from human remains http://www.crimeandclues.com/index.php/death-investigation/66-anthropology/108-the-forensic-anthropologist

·

1. What is the individual's racial affiliation?

2. What is the individual's age and stature?

3. How long has the individual been dead?

4. Is there any evidence of trauma or foul play at or near the time of death?

5. Are there any distinguishing skeletal traits that may aid in establishing the identity?

6. Is there any indication of post-mortem treatment or alteration of the remains?

5 ways that forensic anthropologists might answer these questions http://www.crimeandclues.com/index.php/death-investigation/66-anthropology/108-the-forensic-anthropologist

1. Racial Affiliation

The question of racial affiliation is difficult to answer because, although racial classification has some biological components, it is based primarily on social affiliation. Nevertheless, some anatomical details, especially in the face, often suggest the individual's race. In particular, white individuals have narrower faces with high noses and prominent chins. Black individuals have wider nasal openings and subnasal grooves. American Indians and Asians have forward-projecting cheekbones and specialized dental features.

Example: Examination of a particular skeleton reveals traits consistent with white racial affiliation. Further examination of the skull produces a few strands of straight blonde hair. Microscopic examination shows the hair to be consistent with that of a white person.

2. Age and Stature

Usually, examination of the pubic bone, sacroiliac joint, amount of dental wear, cranium, arthritic changes in the spine, and microscopic studies of bones and teeth narrows the age estimate given by the anthropologist. After examining the skeleton, these indicators suggest that the man was between 35 and 45 years of age at the time of death.

Estimation of stature can be narrowed by measuring one or more complete long bones, preferably a femur or tibia. If stature estimates are based on incomplete long bones, less confidence can be placed in them. This measurement of the maximum length of the bone can then be plugged into a formula based on race and sex to produce an estimate. In the sample case the individual's stature was estimated at 5'7'' to 5'9'' with a mean stature of 5'8.''

3. Time Interval Since Death

Estimating the time interval since death can be extremely difficult. For the most part, such an estimate is based on the amount and condition of soft tissue, such as muscle, skin, and ligaments present, the preservation of the bones, extent of associated plant root growth, odor, and any carnivore and insect activity. However, many other variables must also be considered, including the temperature at the time of death, penetrating wounds, humidity/aridity, soil acidity, and water retention. The longer the time since death, the more difficult it is to determine the time interval since death. In the hypothetical example, the anthropologist determined that the individual died 6 to 9 months previously, based largely on the condition of the soft tissue and the amount of root growth in the individual's clothing.

4. Evidence of Trauma

After the dirt and forest debris were removed from the bones using water and a soft brush, a number of faint cuts became visible in the left ribs and the mid-back. The number of discrete cuts in three ribs and in one vertebra suggest that in the example, the male was stabbed a minimum of three times. No additional evidence of trauma was noted.

5. Distinguishing Skeletal Traits

Further examination revealed that in the example the male sustained a fracture above his right eye and upper jaw bone at least several years before death. The individual also had a severely deviated nasal septum and presented evidence of a severe chronic nasal infection. This observation is noteworthy because if he sought medical help for the fractures or sinus condition, photoimages may have been taken that would provide an excellent opportunity for positive identification.

Post-Examination Procedures

After the forensic anthropologist completes the examination, the medical examiner provides all information obtained from the skeleton to the law enforcement officials investigating the case. The information is then entered in the National Crime Information Center (NCIC).

In this hypothetical case, after several months, a search failed to locate a missing person matching this description. Therefore, the medical examiner and the detectives returned to the forensic anthropologist to request that a facial reproduction be attempted.

Two approaches are available to an anthropologist in reconstructing facial appearance during life. First, the anthropologist could work with a composite artist experienced in rendering sketches based on information supplied by eyewitnesses. Or, the anthropologist could call in a specialist in three-dimensional facial reproduction, a technique in which the head is constructed in clay directly over the skull and mandible or over good casts of them. Because of limited funds, and because an experienced composite artist is available on staff, the forensic anthropologist and artist worked together to produce a drawing of the person represented by the skeletal remains. This drawing was then made available to the public via the local media.

Shortly thereafter, two unrelated men who had seen the image on television came forward because they thought that it might be a relative. Medical and dental records for both individuals could not be located, but facial photographs taken within the last 2 years were available.

Using new techniques of photographic superimposition and comparison, the forensic anthropologist excluded one of the individuals outright. However, frontal photoimages of the second individual taken 3 years before death showed the individual was treated for facial injuries sustained in a motor vehicle accident. The configuration of the frontal sinuses on the photoimages matched exactly the photoimages of the recovered skull, thereby positively identifying the victim.

What a forensic anthropologist does do to aid in a case: http://web.utk.edu/~fac/forensic.shtml

• Goes to a crime scene to assist in the collection of human remains
• Cleans up the bones so that they may be looked at
• Analyzes skeletal remains to establish the profile of the individual
• Looks at trauma evident on the bones to establish the pathway of a bullet or the number of stab wounds
• Works with a forensic odontologist (dentist) to match dental records
• Testifies in court about the identity of the individual and/or the injuries that might be evident in the skeleton

Professor Huld:

I added the following owing to the very recent vintage and the probable employment of at least some of the aforesaid techniques in their analysis and for my prospective reference:

Page last updated at 07:34 GMT, Sunday, 6 December 2009

Ancient site reveals signs of mass cannibalism

By Victoria Gill
Science reporter, BBC News

The site contains remains of 500 "intentionally mutilated" humans

Archaeologists have found evidence of mass cannibalism at a 7,000-year-old human burial site in south-west Germany, the journal Antiquity reports.

The authors say their findings provide rare evidence of cannibalism in Europe's early Neolithic period.

Up to 500 human remains unearthed near the village of Herxheim may have been cannibalised.

The "intentionally mutilated" remains included children and even unborn babies, the researchers say.

The German site was first excavated in 1996 and then explored again between 2005 and 2008.

Team leader Bruno Boulestin, from the University of Bordeaux in France, told BBC News that he and his colleagues had found evidence the human bones were deliberately cut and broken - an indication of cannibalism.

"We see patterns on the bones of animals indicating that they have been spit-roasted," he said. "We have seen some of these same patterns on the human bones [at this site]."

But Dr Boulestin stressed it was difficult to prove that these bones had been deliberately cooked.

Some scientists have rejected the cannibalism theory, suggesting that the removal of flesh could have been part of a burial ritual.

But Dr Boulestin said the human remains had been "intentionally mutilated" and that there was evidence many of them had been chewed.

The early Neolithic was the period when farming first spread in central Europe and the team believes that cannibalism in Europe was likely to have been exceptional - possibly carried out during periods of famine