Author: Jim Foley (jim.foley@FtCollinsCO.ncr.com) Title: Fossil Hominids Update: Jan. 10,

Go to Human Rights activist Keith Henson

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====================================================================== Author: Jim Foley (jim.foley@FtCollinsCO.ncr.com) Title: Fossil Hominids Update: Jan. 10, 1995 ====================================================================== The word "hominid" refers to members of the family of man, Hominidae, which consists of all species on our side of the last common ancestor of humans and living apes. Hominids are included in the superfamily of all apes, the Hominoidae, whose members are called hominoids. Although the number of fossil hominids is not very large, and the evidence is often fragmentary, it is complete enough to give a good picture of the evolutionary history of humans. The time of the split between humans and living apes used to be thought to have occurred 15 to 20 million years ago, or even up to 30 or 40 million years ago. Some apes occurring within that time period, such as Ramapithecus, used to be considered as hominids, and possible ancestors of humans. Later fossil finds indicated that Ramapithecus was more closely related to the orang-utan, and new biochemical evidence indicated that the last common ancestor of hominids and apes occurred between 5 and 10 million years ago, and probably in the lower end of that range (Lewin, 1987). Ramapithecus therefore is no longer considered a hominid. HOMINID SPECIES The species here are listed roughly in order of appearance in the fossil record, except that the robust australopithecines are kept together. Each name consists of a genus name (Australopithecus or Homo) which is always capitalized, and a species name (e.g. africanus, erectus) which is always in lower case. Within the text, genus names are often omitted for brevity. Australopithecus ramidus This species is a recent discovery, announced in September 1994 (White et al.1994; Wood, 1994). It is the oldest known hominid, dated at 4.4 million years. Most remains are skull fragments. Indirect evidence suggests that it was possibly bipedal, and that some individuals were about 122 cm (4'0") tall. The teeth have both apelike and human characteristics, but one baby tooth is very primitive, resembling a chimpanzee tooth more than other known hominid tooth. Other fossils found with ramidus indicate that it may have been a forest dweller. This may cause modification of current theories about why hominids became bipedal, which often link bipedalism with a move to a savannah environment. Australopithecus afarensis Afarensis existed between 3.9 and 2.8 million years ago. Afarensis had an apelike face with a low forehead, a bony ridge over the eyes, a flat nose, and no chin. They had protuding jaws with large back teeth. Cranial capacity varied from about 375 to 500 cc. The skull is similar to that of a chimpanzee, except for the more manlike teeth and larger relative brain size. However their pelvis and leg bones far more closely resemble those of modern man, and leave no doubt that they were bipedal (although adapted to walking rather than running (Leakey, 1994)). Their bones show that they were physically very strong. Females were substantially smaller than males, a condition known as sexual dimorphism. Height varied between about 107 cm (3'6") and 152 cm (5'0"). The finger and toe bones are curved and proportionally longer than in humans (Johanson and Edey, 1981). Some scientists consider this evidence that afarensis was still partially adapted to climbing in trees, other consider it evolutionary baggage. Australopithecus africanus Australopithecus africanus existed between 3 and 2 million years ago. It is similar to afarensis, but body size was slightly greater. Brain size may also have been slightly larger, ranging between 430 and 550 cc. This is consistently larger than ape brains (despite a smaller body size), but still not advanced in the areas necessary for speech. The back teeth were a little bigger than in afarensis, the front teeth a little smaller. Australopithecus afarensis and africanus (and probably ramidus) are known as gracile australopithecines, because of their relatively lighter build, especially in the skull and teeth. Australopithecus aethiopicus This species is known from one major specimen, the Black Skull discovered by Alan Walker, and a couple of other lower jaw specimens which may belong to the same species. The Black Skull is dated at 2.5 million years. It may be an ancestor of robustus and boisei, but it has a baffling mixture of primitive and advanced traits. Parts of the skurticularly the hind portions, are very primitive, most resembling afarensis. Other characteristics, like the massiveness of the face, jaws and single tooth found, and the largest sagittal crest in any known hominid, are more reminiscent of boisei (Leakey and Lewin, 1992). (A sagittal crest is a bony ridge on top of the skull to which chewing muscles attach) Australopithecus robustus Robustus had a body similar to that of africanus, but a larger and more robust skull and teeth. It existed between 2 and 1.4 million years ago. The massive face is flat or dished, with no forehead and large brow ridges. It has relatively small front teeth, but massive grinding teeth in a large lower jaw. Most specimens have sagittal crests. Its diet would have been mostly coarse, tough food that needed a lot of chewing. The average cranial capacity is about 530 cc. Bones excavated with robustus skeletons indicate that they may have been used as digging tools. Australopithecus boisei (was Zinjanthropus boisei) Boisei existed between 2 and 1.1 million years ago. It was similar to robustus, but the face and cheek teeth were even more massive, some molars being up to 2cm across. A few experts consider boisei and robustus to be variants of the same species. Australopithecus aethiopicus, robustus and boisei are known as robust australopithecines, because of their more powerful builds. Homo habilis Habilis, "handy man", was so called because of evidence of tools found with him. Habilis existed between 2.5 and 1.5 million years ago. It is very similar to australopithecines in many ways. The face is still primitive, but it projects less, the back teeth are smaller, and the average brain size, at 650 cc, is considerably larger than in australopithecines. Brain size varies between 500 and 800 cc, overlapping the australopithecines at the low end and Homo erectus at the high end. The brain shape is also more human- like. The bulge of Broca's area, essential for speech, is visible in habilis brain casts, indicates it was probably capable of rudimentary speech. Habilis is thought to have been about 127 cm (5'0") tall, and about 45 kg (100 lb) in weight. Habilis has been a controversial species. Some scientists have not accepted it, believing that all habilis specimens should be assigned to either the australopithecines or Homo erectus. Others believe that habilis combines specimens from two different Homo species. Homo erectus Erectus existed between 1.8 million and 300,000 years ago. Like habilis, the face has protruding jaws with large molars, no chin, thick brow ridges, and a long low skull, with a brain size varying between about 775 to 1225 cc. Early erectus specimens average about 900 cc, while late ones have an average of about 1100 cc (Leakey, 1994). Some Asian erectus skulls have a sagittal crest. The skeleton is more robust than those of modern humans, implying great strength. Study of the Turkana Boy skeleton indicates that erectus may have been more efficient at walking than modern man, whose skeleton has had to adapt to allow for the birth of larger-brained infants. Homo habilis and all the australopithecines are found only in Africa, but erectus was wide- ranging, and is found through Africa and Asia (and was probably in Europe, but no unambiguous skeletal remains are known from there). Evidence from the Peking Man site in China indicates that erectus used fire, and their stone tools are more sophisticated than those of habilis. Homo sapiens (archaic) Archaic forms of Homo sapiens first appear about 500,000 years ago. The brain size is larger than erectus and smaller than modern humans, averaging about 1200 cc. The skeleton and teeth are less robust than erectus, but more robust than modern humans. There is no clear dividing line between late erectus and archaic sapiens, and many fossils between 500,000 and 200,000 years ago are difficult to classify as one or the other. Homo sapiens neanderthalensis Neandertal man existed between 125,000 and 35,000 years ago. The average brain size is slightly larger than that of modern man, about 1450 cc, but this is probably correlated with their greater bulk. The brain case however is longer and lower than that of modern man. Like erectus, they had a protruding jaw and receding forehead and chin. The midfacial area also protrudes, a feature that is not found in erectus or sapiens and may be an adaptation to cold. There are other minor anatomical differences from modern humans. Neandertal bones are thick and heavy, and show signs of powerful muscle attachments. Neandertals would have been extraordinarily strong by modern standards, and their skeletons show that they endured brutally hard lives. They were apparently the first humans to live in very cold climates, and their body proportions were similar to that of modern people who live in cold climates. A large number of tools and weapons have been found, more sophisticated than those of Homo erectus. Neandertals are the first people known to have buried their dead, with the oldest known burial site being about 100,000 years old. Neandertals are found throughout Europe and the Middle East. Western European Neandertals usually have a more robust form, and are sometimes called "classic Neandertals". Neandertals found elsewhere tend to be less excessively robust. (Trinkaus and Shipman, 1992) Homo sapiens sapiens (modern) Modern forms of Homo sapiens first appear about 100,000 years ago. Modern humans have an average brain size of about 1350 cc. About 35,000 years ago, with the appearance of the Cro-Magnon culture, tool kits started becoming markedly more sophisticated, using a wider variety of raw materials such as bone and antler, and containing new implements for making clothing, engraving and sculpting. Fine artwork, in the form of decorated tools, beads, ivory carvings of humans and animals, clay figurines, musical instruments, and spectacular cave paintings appeared over the next 20,000 years. (Leakey, 1994) Even within the last 100,000 years, the long-term trends towards smaller molars and decreased robustness can be discerned. The face, jaw and teeth of Mesolithic humans (about 10,000 years ago) are about 10% more robust than ours. Upper Paleolithic humans (about 30,000 years ago) are about 20 to 30% more robust than the modern condition in Europe and Asia. These are considered modern humans, although they are sometimes termed "primitive". Interestingly, some modern humans (aboriginal Australians) have tooth sizes more typical of archaic sapiens. The smallest tooth sizes are found in those areas where food-processing techniques have been used for the longest time. This is a good example of natural selection which has occurred within the last 10,000 years (Brace, 1983). TIMELINE This diagram shows roughly the times during which each hominid species lived. Ages are in millions of years, with each character position representing 100,000 years. This resolution is a little coarse to accurately represent the most modern species. 5.0 4.0 3.0 2.0 1.0 0.0 |---------|---------|---------|---------|---------| | | | | | | | | |robustus ******* | | | | | boisei **********| | | | aethiopicus * | | | | | | | | | ramidus * | | | | | afarensis ************ | | | | africanus *********** | | | | | | | | | | habilis *********** | | | | | erectus **************** | | | | archaic sapiens *****| | | | | Neandertals *| | | | | modern sapiens * | | | | | | |---------|---------|---------|---------|---------| PROMINENT HOMINID FOSSILS 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 over a thousand hominid fossils. They are however mostly fragmentary, often consisting of a single bone or isolated teeth. Complete skulls and skeletons are very 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 entry will consist of a specimen number if known, any nicknames in quotes (or the site name, if many fossils were found in one place), and a species name. The species name will be followed by a '?' if suspect, or missing if unknown. If the fossil was originally placed in a different species, that name will also be given. Abbreviations: KNM-ER Kenya National Museum, East Rudolf KNM-WT Kenya National Museum, West Turkana SK Swartkrans TM Transvaal Museum OH Olduvai Hominid LH Laetoli Hominid AL Afar Locality ARA-VP Aramis?? Sts ??? "ARA-VP, Sites 1, 6 & 7", Australopithecus ramidus. Discovered by a team led by Tim White, Bernard Asfaw and Gen Suwa (1994) in 1992 and 1993 at Aramis in Ethiopa. Estimated age is 4.4 million years. The find consist 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 arm bone fragments from 2 individuals. AL-128-1, Australopithecus afarensis. Discovered by Donald Johanson in 1973 at Hadar in Ethiopia. Estimated age is about 3.9 million years. This find consisted of portions of both legs, including a complete knee joint which is almost a miniature of a human knee, but apparently belongs to an adult (Johanson and Edey, 1981). It provides the oldest known evidence for hominid bipedalism. AL-288-1, "Lucy", Australopithecus afarensis. Discovered by Donald Johanson in 1974 at Hadar in Ethiopia. Estimated 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 (the larger of the two lower leg bones) 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. AL-333 Site, "The First Family", Australopithecus afarensis? Discovered in 1975 by Donald Johanson's team at Hadar in Ethiopia. Estimated age is about 3.5 million years. This find consisted of remains of at least 13 hominid 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 1976 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. Apart from that, the footprints appear identical to the tracks of modern humans. "Taung baby", Australopithecus africanus Discovered by Raymond Dart in 1924 at Taung in South Africa. The find consisted of a full face, teeth and jaws, and an endocranial cast of the brain. It is probably about 2 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 mature faster than humans, and that the Taung child was about 3). 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 an adult specimen of the same species was discovered in 1936. (*) 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. The Taung baby, and all the other hominids discussed here (with the possible exception of A. ramidus) have a foramen magnum positioned like that of humans. Australopithecus africanus (was Plesianthropus transvaalensis) Discovered by Robert Broom in 1936 at Sterkfontein in South Africa. Sts 5, "Mrs Ples", Australopithecus africanus Discovered by Robert Broom in 1947 at Sterkfontein in South Africa. It consisted of an almost complete, very well preserved skull, minus the lower jaw. The brain size is about 485 cc. Sts 14, Australopithecus africanus Discovered by Robert Broom and J.T. Robinson in 1947 at Sterkfontein. 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 female. The pelvis is far more human than apelike, and is strong evidence that africanus was bipedal. (Brace et al.1979) KNM-WT 17000, "The Black Skull", Australopithecus aethiopicus Discovered by John Walker in 1985 at West Turkana in Kenya. Estimated age is 2.6 million years. This find is a skull with most of the braincase and face intact. 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 Robert Broom in 1938 at Kromdraai in South Africa (Broom, 1938). It consisted of skull fragments, including five teeth. This was the first specimen of robustus. 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. The 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 732, Australopithecus boisei? Discovered by Richard Leakey in 1972 near Lake Turkana. The skull is similar to that of OH 5, but has differences, including the lack of a sagittal crest. Most experts believe this is a case of sexual dimorphism, with the female being smaller than the male. Homo habilis Discovered by the Leakeys in the early 1960s at Olduvai Gorge in Tanzania. A number of fragmentary specimens were found (Leakey et al.1964). OH 7 (Johnny's Child), found by Jonathon Leakey in 1960, consisted of a mandible and two cranial fragments. Estimated age is 1.9 million years. OH 13 (Cindy), found in 1963, consisted of a lower jaw and teeth, bits of an upper jaw and a bit of skull. OH 16 (George), found in 1963, consisted of teeth and some very small skull fragments (George was unfortunately trampled by a herd of Masai cattle before he could be excavated, and much of his skull was lost). Estimated age is 1.7 million years. Twiggy consisted of a crushed cranium and seven teeth. KNM-ER 1470, Homo habilis Discovered by Bernard Ngeneo in 1972 at Koobi Fora in Kenya (Leakey, 1959). Estimated age is 2 million years. This is the most complete habilis skull known. Its brain size was 775 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). The skull is surprisingly modern in some respects, much less robust than any australopithecine skull, and also without the robustness and brow ridges typical of Homo erectus. KNM-ER 1813 Discovered by Kamoya Kimeu in 1973 at Koobi Fora in Kenya. This specimen is similar to 1470, but is much smaller, with a brain size of 510 cc. Estimated age is 1.8-1.9 million years. Some scientists believe this a case of sexual dimorphism, others believe that the brain architecture is different and that 1813 is another species of Homo, and others believe it is an australopithecine. Like the next skull, 1805, this one is in the "Suspense Account" (That makes two out of only 8 hominid skulls discovered in this region). It may be a new species of hominid. (Willis, 1989) KNM-ER 1805, "the Mystery Skull" Discovered by P. Abell at Koobi Fora in Kenya. Estimated age is 1.5 million years. This find consisted of an almost complete cranium and lower jaw containing many teeth. Its cranial capacity is about 600 cc. Some skull features, such as the sagittal crest, are typical of A. boisei, but the teeth are too small for that species. (Willis, 1989; Day, 1986) OH 62, "Dik-dik hominid", Homo habilis? Discovered by Tim White in 1986 at Olduvai in Tanzania. Estimated age is 1.85 million years. The find consisted of portions of skull, arm, leg bones and teeth. The estimated height is very small, maybe about 105 cm (3'5)", and the arms are very long in proportion to the legs. (Johanson and Shreeve, 1989) Trinil 2, "Java man", Homo erectus (was Pithecanthropus erectus) Discovered by Eugene Dubois in 1893 near Trinil in Java. Estimated age is 500,000 years. This find consisted of a flat, very thick skull cap, a few teeth, and a thigh bone found in close proximity (Theunissen, 1989). The estimated brain size is about 900 cc. Trinkaus and Shipman (1992) state that most scientists now believe the femur is that of a modern human, but few of the other references mention this. "Heidelberg Man", Homo erectus? (was Homo heidelbergensis) Discovered by gravel pit workers in 1907 in Germany. Estimated age is about 400,000 years. This find consisted of a complete lower mandible. The teeth are very similar to those of Neandertals, but the jaw is more robust. It is therefore identified as erectus on the basis of its age, but could be an archaic sapiens. "Peking Man Site", Homo erectus (was Sinanthropus pekinensis) Discovered by W. C. Pei at in 1929 at Zhoukoudian, near Beijing, in China. This site yielded many bones from as many as 40 individuals. 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. KNM-WT 15000, "Turkana Boy", Homo erectus Discovered by Kamoya Kimeu in 1984 at Lake Turkana in Kenya. This is an almost complete skeleton of a 9 year old boy. (His age was originally estimated at 11 or 12 years old, but early erectus humans are now thought to have grown faster than modern humans (Leakey, 1994)) It is the most complete known specimen of erectus, and also one of the oldest, at 1.6 million years. At about 168 cm (5'6"), the boy was surprisingly tall, indicating that erectus may have been as tall as modern man. Except for the skull, the skeleton differs only slightly from that of modern boys. (Leakey and Lewin, 1992) KNM-ER 3733, Homo erectus. Discovered by B. Ngeneo in 1975 at Koobi Fora in Kenya. Estimated age is 1.5 million years. This superb find consisted of most of a skull, except for a missing lower jaw. The brain size, at 800 cc, is at the low end of erectus variation. Petralona 1, Homo sapiens (archaic) Discovered by villagers at Petrolona in Greece in 1960. Estimated age is 250,000-500,000 years. This could also be considered as Homo erectus. The brain size is 1220 cc, high for erectus but low for sapiens. Homo sapiens neanderthalensis Discovered by Johann Fuhlrott in 1856 in the Neander valley in Germany. The find consisted of a skull, thigh bones, part of a pelvis, some ribs, and some arm and shoulder bones. The lower left arm had been broken in life, and the bones of the left arm were smaller than those of the right. Fuhlrott recognized it as primitive human, but the German establishment headed by Rudolf Virchow rejected this view, incorrectly claiming that it was a pathological modern human. (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 skull found on Gibraltar in 1848 gathered dust in a museum until it was recognized as Neandertal in 1864.) "Spy 1 and 2", Homo sapiens neanderthalensis Discovered by Marcel de Puydt and Max Lohest in 1886 at 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. They 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. 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 ape-like 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 though to be about 60,000 to 70,000 years old. One of them, Shanidar 4, had apparently been buried with offerings of flowers. Solecki in 1971 wrote a book called "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. "Cro-Magnon Site", Homo sapiens (modern) Discovered by workmen in 1868 at Cro-Magnon in France. Estimated age 28,000 years. The site yielded skeletons of about half a dozen 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 almost 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. 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 Homo habilis and Homo erectus, between erectus and archaic sapiens, or archaic sapiens and modern sapiens. Despite this, there is no 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. The discovery of ramidus is so recent that it is hard to say what effect it will have on current theories. It is generally accepted that Homo erectus is descended from Homo 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. Brain sizes have been given in many cases. It should be noted that brain size can vary widely in a species (between 1000 and 2000 cc for modern humans), and is not usually correlated with intelligence. Between species, however, average brain size, when a correction for body size is applied, is a good indicator of relative intelligence. Chimps, for example, have a brain size between 300 and 400 cc, and weigh between 45 and 80 kg (100 and 175 lbs). Gracile australopithecines had an average brain size of about 450 cc and an upper body weight of about 45 kg (100 lbs), we we can be fairly confident that they were smarter than chimps. Gould (1978) contains a graph which plots brain vs. body size for many apes and hominids, showing that australopithecines and are intermediate between humans and apes in relative brain size. CREATIONIST ARGUMENTS ABOUT HOMINID FOSSILS The usual creationist response to these fossils is to claim that there are no intermediates; each one is either a human or an ape. It doesn't matter that some of the "humans" have a brain size of 550 cc, heavy brow ridges, no chin, and teeth larger than modern ones set in a projecting jaw, or that some "apes" were bipedal, had teeth with many human characteristics, and brains larger than those of similar sized apes. The differences between some Australopithecine and some Homo are smaller than those between the former and apes, or between the latter and modern man, and there are some skulls which cannot be reliably assigned to either genus. Like scientists, creationists find it hard to decide where the dividing line between apes and humans should be. No matter where it is placed, however, the humans just above the line and the apes just below it are going to be more similar to one another than they will be to other humans or other apes. Although scientists put them in genus Homo, most creationists do not accept the smaller- brained habilis specimens as human (but see below). Erectus is more doubtful. Some creationists claim that at least some erectus finds are apes, but others claim they may be degenerate humans: "It may well be that Homo erectus was a true man, but somwhat degenerate in size and culture, possibly because of inbreeding, poor diet and a hostile environment" (Morris, 1974). There is no explanation about why these adverse conditions would cause erectus to be so powerful, and in fact erectus may have been of average human size (see the entry on the Turkana boy fossil). It is also a puzzle why all human skulls over 500,000 years old are erectus, and why, given the number of modern people who face a poor diet and a hostile environment, no erectus specimens are found nowadays. On the other hand, Taylor (1992) gives the following definition: "Homo erectus: an assemblage of bones of a large type of extinct ape; this classification includes "Peking Man" and "Java Man". The brain size of erectus skulls can exceed 1200 cc, about 90% of the average size for a modern human. Despite the primitive features, they are unmistakably human, and it is impossible to call them apes. The skull 1470 was discovered in 1972, and publicized as both amazingly human-like, and extremely old, at nearly 3 million years. Creationists eagerly seized on the statement of Richard Leakey, its discoverer, that 1470 "wipes out everything we have been taught about human evolution, and I have nothing to offer in its place". Creationists sometimes give the impression that it is a modern human skull. But despite its human features, it has a brain size of about 775 cc. Gish (1984) is honest enough to point out its small size, but states that its age and sex is unknown, presumably seeking to imply that it might belong to a child. That is not probable, as can be seen from comparative photos (Weaver, 1985). 1470's face is as large as that of a modern Cro-Magnon skull, despite a much smaller brain size, and the cranium has a markedly different shape. It is interesting to note that, as a debating tactic to discredit other hominid fossils, creationists often accept 1470 as human, even though many of them reject larger- brained erectus specimens as apes. But if 1470 is human, one could then make a strong case that the very similar but smaller skull 1813 is also human (a photographic comparison is in Weaver (1985)). Creationists, however, are unlikely to find the idea of a human with a brain size of 510 cc very appealing. No creationist who discusses this subject avoids mentioning Piltdown Man or Nebraska Man. Piltdown Man (Eoanthropus dawsoni) was discovered in England in 1912, and a second specimen in 1915. It consisted of a surprisingly modern-looking skull associated with a surprisingly ape-like lower jaw. In 1953 it was discovered to be a hoax, consisting of a modern human skull and an orang-utan jaw. Well before then, Piltdown had become a puzzling anomaly when compared to all other hominid jaws, and the scientific community was relieved to be able to forget about it. The paleontological community was horribly embarrassed by the uncovering of Piltdown, and justifiably so. A number of scientists had made what were in retrospect extremely foolish statements about the skull, elaborating on its "unmistakably apelike characteristics." Piltdown's acceptance was probably helped by the fact that it conformed to prejudices about what a primitive human skull would look like. In fact a number of scientists did believe that the cranium and jaw were not from the same creature, but no- one had suspected forgery. Nebraska Man (Hesperopithecus haroldcookii) was named from two human-like teeth found in 1922. As creationists tell it, evolutionists used one tooth to build an entire species of primitive man, complete with illustrations of him and his family, before further excavations revealed the tooth to belong to a pig. The other side of this story is told by Gould (1991). The finders, and the scientific community, never identified the tooth as belonging to a human ancestor, only to a higher primate. The imaginative drawing was the work of an illustrator collaborating with an English scientist, and was done for the Illustrated London News, not for a scientific publication. Identifying the tooth as belonging to a higher primate was not as foolish as it sounds; pig cheek teeth are extremely similar to those of humans, and the specimen was worn, making identification even harder. Creationists also claim that Nebraska Man was used as proof of evolution during the Scopes Monkey Trial in 1925, but this claim is apparently apocryphal, since no scientific evidence was presented at the trial. Nebraska Man should not be considered an embarrassment. The scientists involved were mistaken, but not incompetent or dishonest. The whole episode was actually an excellent example of how the scientific process should work. Given a problematic identification, scientists went out, found further data which falsified their earlier ideas, and promptly abandoned them. This is a marked contrast to the creationist approach. Many creationists, including Duane Gish (1984), have claimed that Java Man, discovered by Eugene Dubois in 1893, was "bad science". Gish says that Dubois found two human skulls at "nearby" Wadjak at the same level and had kept them secret, that Dubois later decided Java Man was a giant gibbon, and that the bones do not come from the same individual. Most people would find Gish's meaning of "nearby" surprising: the Wadjak skulls were found 100 miles of mountainous countryside away from Java Man. Similarly for "at the same level": the Wadjak skulls were found in cave deposits in the mountains, while Java Man was found in river deposits in a flood plain (Fezer, 1993). Dubois had reported the Wadjak skulls in three separate publication around 1890, but, recognizing that they were modern, devoted all his attention to Java Man once it was found. Based on his own theories about how brains had evolved and wishful thinking, Dubois did claim that Java Man had the proportions of a giant gibbon, but never said that it was one, and never stopped believing that he had found an ancestor of modern man (Theunissen, 1989; Gould, 1993). It may be true that the femur and skull cap do not belong together, but the skull cap definitely does not belong to any ape. It is far too large, and is clearly related to the many other Homo erectus fossils that have been found, which creationists often recognize as human. Peking Man is another favorite target. Creationists claim that the Peking Man fossils are the remains of apes or monkeys eaten by real humans, that the original fossils may have been disposed of to conceal the evidence of fraud, that only models of the fossils remain, and they are distorted to fit evolutionist preconceptions (Gish, 1984). Like Java Man, the skull fragments are clearly those of Homo erectus, and there is no evidence that they were the victims of cannibalism. The idea that there was a conspiracy to distort the evidence and then dispose of the skulls would be a far- fetched fantasy even if there were no evidence contradicting it. However since the war, further discoveries have been made, at the original site and other sites in China, that are similar to the older fossils. This refutes the charge that evolutionists doctored Peking Man to create evidence for evolution. Finally, the claim that only imaginative models remain is false; there are excellent casts, photos, and many descriptive papers were written on the fossils. Some creationists point to Olduvai Gorge, where australopithecines are found contemporaneously with Homo habilis and erectus, above another layer which contains the remains of a circular stone habitation, apparently made by humans. How could australopithecines be the ancestor of habilis, or habilis of erectus, if they are all found together? And how could erectus be the ancestor of modern man, if traces of modern man are found below it? There are a number of errors in this reasoning. First, the australopithecines in question are robust, and are not considered as ancestors of Homo. Even if they were, there is no reason why they could not exist at the same time as a descendant species. A new species can form by splitting off its parent. There is no reason that the parent species must become extinct, otherwise the total number of species could never increase. Finally, the claim that the stone circle is an artifact has been dropped. It is only a rough arrangement, and could have just as easily have been formed by water or other activity at any time in the past. Even if it was artificial, there is no reason to believe that habilis or erectus would have been incapable of making it. Creationists say things about Neandertals such as: "The creationists in those days [the 1860's] responded 'Now wait a minute. Neanderthals are just plain people, some of whom suffered bone disease'" "Nowadays, evolutionists agree with creationists: Neanderthals were just plain people, no more different from people living today than people than one living nation is different from another" Parker in (Morris and Parker, 1982). "Nowadays, Neanderthal Man is classified as Homo sapiens, completely human" (Huse, 1983). Actually, Neandertals are classified as Homo sapiens neanderthalensis, a subspecies of man, in recognition of consistent differences such as heavy brow ridges, a long low skull, a robust skeleton, and others. (Some scientists believe the differences are large enough to justify a separate species, Homo neanderthalensis) Evolutionists last century claimed that these were real differences between us and Neandertals, and they were right. Creationists claimed that the differences were a result of various diseases, and they were wrong. For Parker to claim that creationists won this debate is a rewriting of history. Amazingly, a century after scientists knew otherwise, many creationists still believe that Neandertals were merely diseased modern humans. Duane Gish, in a debate with Michael Shermer, said that Neandertals were simply modern humans with rickets (or arthritis). Malone (1994) agreed: "However, more recent tests have revealed that all of the specimens [he is talking about discoveries from the late 1800's] suffered from pathological diseases such as rickets or arthritis". (I suspect these tests are either fictional or misrepresented) Some, but by no means all, Neandertals have been found with signs of these and other health problems. But Neandertals have many distinctive features, and there is no reason why these diseases (or any others) would cause any, let alone all, of these features on even one, let alone many, individuals. Modern knowledge and experience also contradicts the idea that disease is a cause of Neandertal features. Straus and Cave (1957) made a striking comment about Neandertals: "Notwithstanding, if he could be reincarnated and placed in a New York subway - provided that he were bathed, shaved, and dressed in modern clothing - it is doubtful whether he would attract any more attention than some of its other denizens". This may be a source of the creationist idea that Neandertals are "just plain people" (Morris and Parker, 1982). Note, though, that that is not what the quote says. Anyone who has travelled the Big Apple's subway will probably agree that Neandertals could look quite odd and still meet Straus and Cave's rather lax criterion. Gish (1984) distorts this quote by claiming that a Neandertal in a business suit could walk down a city street and not attract more attention than any other individual, a statement which is probably false. Johanson and Edey (1981) extend the example by saying that if you put Homo erectus on a subway, "people would probably take a suspicious look at him". Put Homo habilis on the subway, and "people would probably move to the other end of the car". Berra (1990) states that "if cleaned up, shaved and dressed in business suits, [Neandertals] could probably pass for television evangelists." The exhibit on Neandertals at ICR Museum says (or used to say) "Many Neanderthal features are similar to those in elderly humans today. Since humans lived to great ages in the initial generations after the flood and Babel, perhaps the features are primarily due to advanced age...". In fact, none of the distinctive features of Neandertals are similar to those of old people, least of all powerful bones and muscles. Whoever wrote this presumably also thinks that Neandertals are arthritic modern humans. The following quote from Trinkaus and Shipman (1992) refutes claims that Neandertals differ no more from modern humans than living races do from each other: "Rare individuals among modern humans may share one, or even a few, of the anatomical characteristics of Neandertals, but not one human - much less any population - can be found that possesses the entire constellation of traits that define Neandertals" (p 412). A common creationist claim is that humans existed alongside or predated all of their presumed ancestors in the fossil record. Taylor (1992) contains a long list of supposed examples (with the disclaimer "Remains which some researchers have suggested (but _not_ proven) as evidence that the various "missing links" were contemporaneous, or that man and these creatures were contemporaneous"). Many of these cases are various hominid fossils which appear in the correct position in the fossil record. Some of these have already been mentioned: the Petralona specimen, 1470, the Turkana Boy, and the Krapina specimens. Other examples are: Laetoli footprints: creationists invariably mention the close resemblance between these and modern human footprints, but usually neglect to mention their extremely small size and the fact they match the feet of the australopithecines living at the same time. KP 271, "Kanapoi Hominid": this is a very worn fragment of a lower left humerus (the upper arm bone), discovered by Brian Patterson in 1965, which is probably between 4 and 5 million years old. Hoesch and Rajca (1994) state that this is indistinguishable from a human bone, Parker and Morris (1982) state that it is a human bone. Both neglect to mention that its small size is even better evidence that it belongs to an australopithecine. Swanscombe Man: two cranium fragments discovered in 1935 and 1936 by Alvan Marston in England, and a third fragment, discovered in 1955, which fit with the earlier fragments. The bones are modern in form, but exceptionally thick, with an estimated brain size of 1325 cc. They are probably from an archaic Homo sapiens, a view compatible with their estimated age of 200,000 to 300,000 years. (Day, 1986) Fontechevade Man: a skullcap fragment which is difficult to classify, and whose dating is doubtful, it is probably also an archaic sapiens. Of the other "anomalous" hominid fossils, most are of fossil humans that have since been discovered to be intrusions, i.e. they have been buried in deposits that are older than they are. Examples are: Oldoway Man: a skull and skeleton found by Hans Reck at Olduvai in 1913. In 1932 it was shown to be a modern Homo sapiens, buried 20,000 years ago in older deposits that had been exposed by faulting. (Johanson and Shreeve, 1989) Kanjera Man, Kanam Jaw: discovered by Louis Leakey in 1932, and claimed by him to be very old. The dating however proved to be uncertain, and both are probably modern bones. (Johanson and Shreeve, 1989; Lewin, 1987) Castenedolo Man: Morris and Parker (1982) say "Fossils of ordinary people in Mid Tertiary rock [i.e. tens of millions of years old; the actual date is about 1.5 million years] were found in Castenedolo, Italy back in the late 1800's...". An official report on these skeletons in 1899 noted that all the fossils from the deposit were impregnated with salt, except the human ones. This implies that they are from relatively recent burials. Collagen tests in 1965 and radiocarbon dating in 1969 confirmed this. Galley Hill Man: this was a modern-looking skeleton discovered in 1888 in old deposits. Even last century, many thought it was a modern human, and this was confirmed in 1948 when it was fluorine dated (Trinkaus and Shipman, 1992). Henry Morris has claimed (1974) that since 10,000 year old Homo erectus skulls were found at Kow Swamp in Australia, erectus cannot be the ancestor of modern man. The logic is faulty, since there is no reason that a population of erectus could not have survived long after Homo sapiens first appeared. Morris also has his facts wrong. Characteristics of the Kow Swamp skulls led to suggestions that some Homo erectus _genes_ had survived in them, as the quote Morris gives from the source material clearly states. Morris' claim that they are erectus _skulls_ is incorrect. In 1987, creationist Tom Willis claimed that the skeleton known as "Lucy" consisted of bones that had been found at two sites about 1.5 miles (2.5 km) apart. Willis had actually confused two separate finds which belong to the same species. This was a spectacular error which could hardly have been made by anyone who had done the most elementary research, but it didn't stop a number of other creationists from picking up the claim and repeating it. For a full history of this claim, read the talk.origins knee-joint FAQ file (Lippard, 1994). In 1950, Wilfred Le Gros Clark published a paper which definitively settled the question of whether the australopithecines were apes or not. He performed a morphological study (based on the shape and function) of teeth and jaws, since these formed most of the fossil evidence. By studying human and modern ape fossils, Le Gros Clark came up with a list of eleven consistent differences between humans and apes. Looking at A.africanus and robustus (the only australopithecine species then known), he found that they were humanlike rather than apelike in every characteristic. Judged by the same characteristics, A.afarensis falls somewhere between humans and apes, and probably closer to the apes (Johanson and Edey, 1981). White et al. (1994) did not judge A.ramidus by these criteria, but it is clear that ramidus is even more chimpanzee-like than afarensis. The ramidus arm bones also display a mixture of hominid and ape characteristics. Solly Zuckerman attempted to prove with biometrical studies (based on measurements) that the australopithecines were apes. Zuckerman lost this debate in the 50's, and his position was abandoned by everyone else (Johanson and Edey, 1981). Creationists like to quote his opinions as if they were still a scientifically acceptable viewpoint. Creationists are also reluctant to accept that australopithecines, including Lucy, were bipedal. A statement by Weaver (1985) that "Australopithecus afarensis ... demonstrates virtually complete adaptation to upright walking" is dismissed by Willis (1987) as "a preposterous claim". Willis adds: "Many competent anthropologists have carefully examined these and other "Australopithicine" [sic] remains and concluded that Lucy could not walk upright." Willis' evidence for this consists of a statement by Solly Zuckerman made in 1970; a 1971 statement from Richard Leakey that australopithecines "may have been knuckle-walkers", and a quote from Charles Oxnard about the relationship between humans, australopithecines and the apes. It is worth noting that two of these three quotes were made before Lucy, and A. afarensis, was even discovered. Zuckerman's views have long since been discredited. Leakey was merely making a suggestion, not stating an opinion, and he has since stated (1994) that Lucy "undoubtedly was a biped". Oxnard has some unorthodox opinions about the australopithecines, but he has also stated that they were bipedal, just not in the human manner (Oxnard, 1987). Furthermore, the Oxnard quote supplied by Willis discusses neither bipedality nor A. afarensis. "From the neck down, certain clues suggested to Johanson that Lucy walked a little more erect than today's chimps. This conclusion, based on his interpretation of the partial hip bone and a knee bone, has been hotly contested by many paleoanthropologists." (Morris, 1994) Almost everything in this quote is a distortion (Johanson's and Lucy's names are about the only exceptions). "Certain clues suggested" doesn't mention that the whole find screamed "bipedality" to every qualified scientist who looked at it. "a little more erect", when everyone believes that Lucy was fully erect. "the partial hip bone and a knee bone", when Lucy included almost a complete pelvis and leg (taking mirror imaging into account, and excluding the foot). "has been hotly contested", when no reputable paleoanthropologist denies that Lucy was bipedal. The debates are about whether she was also partly arboreal, and about how similar the biomechanics of her locomotion was to that of humans. Given that we have most of Lucy's leg and pelvis, one has to wonder what sort of fossil evidence it would take to convince creationists of australopithecine bipedality. Fossil footprints? No, we have those. Fossilized Reeboks? Creationist consider all australopithecines apes. There is some justification for that, since most people would probably call one an ape if they saw it. But they were bipedal apes with humanlike teeth and an enlarged brain, a good candidate for human ancestors. FURTHER READING Two creationist books dealing specifically with the hominid fossil record, which I have not yet read, are Malcom Bowden's "Ape-Men: Fact or Fallacy?" and Marvin Lubenow's "Bones of Contention". Of the creationist books listed here, Gish (1984) deals most extensively with the topic of hominid fossils. Short articles which give a good account of human evolution are Weaver (1985), Brace (1983) and Berra (1990). For good book-length treatments, I would recommend Johanson and Edey (1981), Willis (1989), and Trinkaus and Shipman (1992), which is more wide-ranging than its title might indicate. Academic works of interest are Brace et al. (1979), which contains line drawings and brief descriptions of about 50 important fossils, and Day (1986), which contains a far more extensive and detailed list of fossils obtained from about 50 major sites, along with many photographs. This FAQ file will be added to on a regular basis. Contact the author (jim.foley@ftcollinsco.ncr.com) with corrections, criticisms, or suggestions for further topics. REFERENCES Berra, T.: The evolution of life and the rise of humans. In: Evolution and the myth of creationism, Stanford,California:Stanford University Press, 1990, p. 70-119. Brace C.L., Nelson H., Korn N. and Brace M.L.: Atlas of human evolution, Holt, Rinehart and Winston, 1979. Ed. 2 Brace, C.L.: Humans in time and space. In: Scientists confront creationism, edited by Godfrey, L.R. Toronto:George J. McLeod, 1983, p. 245-282. Broom R.: The pleistocene anthropoid apes of south africa. Nature 142:377-379, 1938. (announcement of the discovery of Australopithecus robustus) Day M.H.: Guide to fossil man, Chicago:University of Chicago Press, 1986. Ed. 4 Fezer K.D.: Creation's incredible witness: Duane T. Gish, Ph.D. C/E 13(2):5-21, 1993. Gish D.T.: Evolution: the fossils say no, San Diego:Creation-Life Publishers, 1984. Ed. 3 Gould, S.J.: Sizing up human intelligence. In: Ever since Darwin, Pelican Books, 1978, p. 179-185. Gould, S.J.: An essay on a pig roast. In: Bully for brontosaurus, New York:W.W.Norton, 1991, p. 432-447. Gould, S.J.: Men of the thirty-third division. In: Eight little piggies, New York:W.W.Norton, 1993, p. 124-137. Hoesch B. and Rajca J.: Another attempt at a missing link. Science, Scripture and Salvation (ICR radio show) Nov 5:1994. Huse S.M.: The collapse of evolution, Baker Book House Company, 1983. Johanson D.C. and Edey M.A.: Lucy: the beginnings of humankind, New York:Simon and Schuster, 1981. pp. 1-409. Johanson D.C. and Shreeve J.: Lucy's child: the discovery of a human ancestor, New York:Early Man Publishing, Inc, 1989. Leakey L.S.B.: A new fossil skull from olduvai. Nature 184:491-493, 1959. (announcement of the discovery of Australopithecus boisei) Leakey L.S.B., Tobias P.V. and Napier J.R.: A new species of the genus homo from olduvai gorge. Nature 202:7-10, 1964. (announcement of the discovery of Homo habilis) Leakey R.E.: The origin of humankind, New York:BasicBooks, 1994. Leakey R.E. and Lewin R.: Origins reconsidered: in search of what makes us human, New York:Doubleday, 1992. Lewin R.: Bones of contention, New York:Simon and Schuster, 1987. (discusses in detail some of the major controversies that have occurred in paleoanthropology) Lippard J.L.: Lucy's knee joint: how creationists deal with their errors, 1994. (talk.origins FAQ file) Malone B.: Search for the truth: A-1 anthropology, 1994. (posted on talk.origins newsgroup) Morris H.M.: Scientific creationism, Santee,California:Master Books, 1974. Morris H.M. and Parker G.E.: What is creation science? San Diego:Creation-Life Publishers, 1982. Morris J.D.: Has the "missing link" been found? Acts & Facts 23(11):1994. Oxnard C.: Fossils, teeth and sex, Hong Kong:Hong Kong University Press, 1987. Straus W.L.,Jr. and Cave A.J.E.: Pathology and posture of neanderthal man. Quarterly Review of Biology 32(4):348-363, 1957. Taylor P.S.: The illustrated origins answer book, Mesa,Arizona:Eden Productions, 1992. Ed. 4 Theunissen B.: Eugene Dubois and the ape-man from java, Dordrecht,The Netherlands:Kluwer Academic Publishers, 1989. Trinkaus E. and Shipman P.: The neandertals, New York:Alfred E. Knopf, 1992. Weaver K.F.: The search for our ancestors. National Geographic 186(5):560-623, 1985. White T.D., Suwa G. and Asfaw B.: Australopithecus ramidus, a new species of early hominid from Aramis, Ethiopia. Nature 371:306-312, 1994. Willis Delta: The hominid gang, New York:Viking, 1989. Willis Tom: Lucy goes to college. Bible-Science Newsletter January:1-3, 1987. Wood B.A.: The oldest hominid yet. Nature 371:280-281, 1994.

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