|Exciting new evidence about Homo erectus, see below!|
A few authors do mention other erectus fossils in passing. Morris suggests, although it is not clear which specimens he is referring to, that they are degenerate humans:
"It may well be that Homo erectus was a true man, but somewhat degenerate in size and culture, possibly because of inbreeding, poor diet and a hostile environment" (Morris 1974).
Gish (1985) suggests that many erectus fossils would have been attributed to Neandertal Man were it not for their supposed age, and hence probably also considers the erectus morphology, like that of the Neandertals, to be caused by disease.
There is no explanation of why these adverse conditions would cause H. erectus to be so physically powerful, and in fact many erectus may have been of average human size (see the entry on the Turkana Boy fossil). Nor is it explained 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.
Bowden (1981) briefly discusses ER 3733, but so vaguely that it is difficult to determine whether he thinks it is an ape or a human! This fossil, despite massive brow ridges and other primitive features, is so complete and looks so human that it seems unlikely anyone would call it an ape (and no other creationists have done so). It seems equally unlikely that Bowden would call it a human, since he acknowledges its similarity to the Peking Man skulls which he claims are apes, and all of which are larger than 3733. Bowden escapes this dilemma by instead casting aspersions on the accuracy of ER 3733's reconstruction (almost all other creationists solve it by not mentioning ER 3733).
Bowden's even briefer mention of OH 9 is just as cryptic. He notes its similarities to both Pithecanthropus [ape] and a Neandertal [human] skull. In one sentence he refers to it as "surprisingly advanced", but the next paragraph starts: "Reviewing all these fossil apes, ...". Bowden's description of OH 9 makes it sound so intermediate in nature between apes and humans that, once again, it is difficult to decide what he thinks it is.
One Homo erectus specimen, the Turkana Boy, is recognized by Gish as human. Unavoidably, since it is an erectus skull attached to a body that is almost completely modern. Gish (1985), writing soon after it was discovered, cautiously suggests that except for the brain size, all major aspects of the skeleton are within the limits of Homo sapiens, and that were it not for the estimated age of 1.6 million years it would be assigned to that species. In a later assessment (1995) Gish says that the size and shape of the braincase and a few characteristics of the body were the only differences from a modern human. Menton (1988) similarly states that WT 15000 was classified as H. erectus only because of its age.
That is incorrect; the Turkana Boy has a typical erectus skull, differing from modern humans in many aspects other than brain size. It is more similar to 1470 (H. habilis), or to other erectus specimens such as the Peking Man braincases, than it is to modern humans. It is strikingly similar to the Peking Man reconstruction made by Weidenreich, which even Gish agrees looks to be "intermediate between the Anthropoid Apes and Man".
The skeletal differences are less obvious, but in combination they show a skeleton with small but significant differences from modern humans. The length of the neck and the neck-shaft angle in the femur are respectively "well over 3" and 5 standard deviations from the modern human norm (Brown et al. 1985). The boy was extraordinarily strong, and his spinal cord had less than half the cross-sectional area of ours (Walker and Shipman 1996). According to Richard Leakey, "practically every piece of bone shows minute but unquestionable differences from modern man" (Angela 1993). Gish stresses the skeletal similarities but ignores these differences.
Menton (1988) states that the Turkana Boy was like a modern human "except for certain details of the skull", and then adds that:
"He had a low forehead and pronounced brow ridges not unlike some races of modern man. Richard Leaky [sic] said that this boy would go unnoticed in a crowd today." (Menton 1988)Menton has taken this quote out of context, omitting some text that significantly changes its meaning:
"Suitably clothed and with a cap to obscure his low forehead and beetle brow, he would probably go unnoticed in a crowd today." (Leakey and Walker 1985)
"In our view, there are two alternatives. We should either admit that the Homo erectus/Homo sapiens boundary is arbitrary and use nonmorphological (i.e. temporal) criteria for determining it, or Homo erectus should be sunk [into H. sapiens]."
Wolpoff and his colleagues support what is known as the multiregional theory, which holds that populations of H. erectus throughout the world evolved together towards H. sapiens (as opposed to the "out of Africa" theory, which holds that one population of H. erectus gave rise to all modern humans).
Wolpoff et al. are not saying that H. erectus cannot be distinguished from modern humans; in fact they point out that it "on the average shows clear morphological distinctions from Homo sapiens". Nor do they dispute that H. sapiens evolved from H. erectus. Wolpoff and his colleagues explain clearly why they propose that H. erectus should not be a separate species:
We regard the species distinction between Homo erectus and Homo sapiens as being problematic. The issue we address stems from the difficult in clearly distinguishing an actual boundary between Homo erectus and Homo sapiens. ... From a purely cladistic outlook, Homo erectus should be sunk, since species originating through anagenesis (ie, without branching) are not recognized as separate species according to the criteria of phylogenetic systematics. (Wolpoff et al. 1984)
In other words, they propose sinking H. erectus into H. sapiens only because there are so many intermediate fossils that it is difficult to define a boundary between them, and because there are theoretical reasons for calling them the same species (no matter how much anatomical difference there is) if, as the multiregionalists believe, H. sapiens did not branch off from a subset of the H. erectus population. Wolpoff and his colleagues are not saying that the two species should be merged because there is insufficient difference between them, and Wolpoff has confirmed to me (in an email) that the amount of difference is not the issue.
Most scientists disagree with the idea of sinking H. erectus into H. sapiens, believing that the differences are clearly enough to merit a species distinction. A growing number would go further, and argue that there is room for another species between them, Homo heidelbergensis, which would contain many of the fossils often called "archaic" Homo sapiens (Tattersall 1995). It is also far from certain that the multiregional theory is correct, in which case even the theoretical reasons for sinking H. erectus would disappear.
Scientists who propose sinking H. erectus therefore provide no comfort for creationists, since their reasons totally contradict creationists who would claim that the H. erectus morphology is caused by diseases of, or racial variation in, H. sapiens.
One occasionally sees creationists claiming that many scientists now believe that H. erectus is no longer a valid species. This was never true. Shipman (2003) discusses a conference in 1991 at which a proposal by Wolpoff, Thorne and their colleagues to abandon H. erectus as a species was a contentious topic. Even then, the proposal did not get far and since then it has faded away. As Shipman says, "The move to eliminate Homo erectus is largely defunct...".
In 2002, Vekua et al. announced the discovery of D2700, a new hominid skull from Georgia (in the ex-USSR), following the discovery of two earlier skulls (Gabunia et al. 2000). These three skulls are most similar to those of early African H. erectus specimens, but are quite primitive and also share a number of characteristics with H. habilis skulls. Their brain sizes range from 780 cc (previously the lower end of the erectus range) down to 600 cc, which is in the middle of the H. habilis range. Taken as a group, these three skulls extend the anatomical range of erectus beyond anything that could conceivably be attributed to Homo sapiens. Both in anatomy and brain size, they bridge the gap between H. erectus and H. habilis.
See the D2700 page for more information about these fossils.
Angela P. & P. (1993): The extraordinary story of human origins. Buffalo NY: Prometheus Books.
Bowden M. (1981): Ape-men: fact or fallacy? Ed. 2. Bromley,Kent: Sovereign.
Brown F., Harris J., Leakey R.E., and Walker A.C. (1985): Early Homo erectus skeleton from west lake Turkana, Kenya. Nature, 316:788-92. (announcement of the discovery of the Turkana Boy skeleton)
Gabunia L., Vekua A., Swisher C.C., III, Ferring R., Justus A., Nioradze M. et al. (2000): Earliest Pleistocene hominid cranial remains from Dmanisi, Republic of Georgia: taxonomy, geological setting, and age. Science, 288:1019-25.
Gish D.T. (1985): Evolution: the challenge of the fossil record. El Cajon, CA: Creation-Life Publishers.
Huse S.M. (1983): The collapse of evolution. Baker Book House Company.
Lubenow M.L. (1992): Bones of contention: a creationist assessment of human fossils. Grand Rapids,MI: Baker Books.
Mehlert A.W. (1994): Homo erectus 'to' modern man: evolution or variability? Creation Ex Nihilo Technical Journal, 8(1):105-16.
Menton D.N. (1988): The scientific evidence for the origin of man. (a creationist article)
Morris H.M. (1974): Scientific creationism. Santee,California: Master Books.
Morris H.M. and Parker G.E. (1982): What is creation science? San Diego: Creation-Life Publishers.
Shipman P. (2000): Doubting Dmanisi. American Scientist, Nov-Dec 2000
Taylor P.S. (1992): The illustrated origins answer book. Ed. 4. Mesa,Arizona: Eden Productions.
Vekua A., Lordkipanidze D., Rightmire G.P., Agusti J., Ferring R., Maisuradze G. et al. (2002): A new skull of early Homo from Dmanisi, Georgia. Science, 297:85-9. (D2700)
Walker A.C. and Shipman P. (1996): The wisdom of the bones. New York: Alfred E. Knopf. (a popular history of Homo erectus and the discovery and analysis of the Turkana Boy skeleton)
Wolpoff M.H., Wu X.Z., and Thorne A.G. (1984): Modern Homo sapiens origins: a general theory of hominid evolution involving the fossil evidence from east Asia. In F.H. Smith & F. Spencer (Eds.), The origins of modern humans. (pp. 465-7). New York: Alan R. Liss.
This page is part of the Fossil Hominids FAQ at the talk.origins Archive.
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