The Singapore New Paper’s (7th Sep 2004) article entitled, “No, our ancestors did not move around like chimps” revealed an ignorance of the actual debate and disagreement among anthropologists with regard to the status of Orrorin tugenensis as a “missing-link” for human evolution.[2] The emphatic claim that “human beings’ early ancestors walked upright six million years ago” omits the controversial evidence surrounding this particular “hominid”. This is typical of current evolutionary propaganda, which is concerned with indoctrination rather than education.
Dr Robert Eckhardt, a professor in the Laboratory of Comparative Morphology and Mechanics at Pennsylvania State University, commented that, “We have solid evidence of the earliest upright posture and bipedalism securely dated to six million years.” The “solid evidence” for bipedalism was based upon 13 flimsy fossil fragments comprising broken femurs, jaw bones and several teeth. It was glaringly lacking in cranial material.
The fossil fragments that form Orrorin tugenensis were found in the Tugen Hills of Kenya in the fall of 2000 by Brigitte Senut and Martin Pickford of France, and have been controversial ever since. The New Paper article did not report or mention the opposing opinions of various experts concerning Orrorin, such as those of Professor Leslie Aiello of London University. He disclosed that the claim of this species walking upright was not sustainable and considered it more probable for this species to have been the ancestor of apes rather than man.[3] Professor Chris Stringer of the Natural History Museum London also expressed his doubts.
If Orrorin were considered to be a human ancestor, it would predate other candidates by around 2 million years. Senut and Pickford (in an even more drastic scenario) had suggested that all the australopithecines, even those considered by evolutionists to be our direct ancestors, should be relegated to a dead-end side branch in favor of Orrorin. Pickford et al. stated that, “If we are correct, then Australopithecus may represent a side branch in hominid evolution that became extinct without giving rise to Homo . . . .”[4] Yet paleontologist David Begun of the University of Toronto had admitted that scientists had been unable to determine whether Orrorin was, in fact, “on the line to humans, on the line to chimps, a common ancestor to both, or just an extinct side branch.”[5]
There were speculations and accusations that the fossils were collected illegally. These were denied and seemed to be unproven.[6] Controversies regarding the status of Orrorin rage on, but no credible evidence of a creature on its way to becoming human is ever found.
The Leakey Foundation had also expressed its doubts about Orrorin. In its article “Bright Future for the Human Past”, the Foundation stated that although “Orrorin’s discoverers contend that it (Orrorin) represents the earliest bipedal hominid”, “many experts are witholding judgment.” It further explained, “regarding Orrorin’s hominid status, Haile-Selassien (anthropologist) believes that the Kenyan creature’s canine looks too primitive and evidence for bipedalism from the thigh bone is unclear. The Tugen Hills fossils (Orrorin) could just as plausibly represent an exclusive ancestor of apes, or a dead end.”[7]
According to Science, many “doubt that the bones even belonged to a hominid – a loose classification that currently includes the australopithecines and the genus Homo – or even that the species they belonged to walked on two feet.”[8] Lucy’s co-discoverer Donald Johanson, director of the Institute of Human Origins at Arizona State University in Tempe, argued that, “The case for a hominid is weak.”[9]
With regard to the claim that Orrorin was bipedal, Science noted that “the femur argument has gotten a lukewarm reception from others. They (experts) point out that many male specimens of Lucy’s species – Australopithecus afarensis – have much larger femoral heads than Lucy’s.”[10] A.L. 288-1 (“Lucy”) is a female of a highly dimorphic species. Since sexual dimorphism decreases gradually through the australopithecine line, it is expected that an earlier ancestor would be even more dimorphic. Therefore, “few researchers agree with Senut’s contention that these larger specimens (Orrorin) belong to another species.”[11]
Science concluded with this remark, “These conflicting views reflect the fact that experts lack a clear definition of a hominid, says Jeffrey Schwartz of the University of Pittsburgh. But that only means researchers seeking to penetrate our shadowy origins will be debating Pickford and Senut’s find for years.”[12] It is amazing that after decades of research in paleoanthropology, experts have not arrived at a conclusive definition for “hominids”.
Pickford et al. claimed that the femora showed evidence of bipedal locomotion, if not obligate bipedalism. Much of the deduction came from CT scans of the femur BR1002’00. According to Robert Eckhardt, professor of developmental genetics and evolutionary morphology at Penn State’s Laboratory of Comparative Morphology and Mechanics (LCMM) in the department of kinesiology, the femoral neck “cortex is thickest inferiorly and thinnest superiorly. However, the cortex superiorly, anteriorly and posteriorly is relatively thicker than it is in humans, but appreciably thinner than it is in African apes.”[13] We must immediately note that the measurement of the width of thin structures such as the cortical shell of the vertebral body or femoral neck with computed tomography (CT) is limited by the spatial resolution of the CT system.[14]
In chimpanzees and gorillas, the thicknesses in the upper and lower parts of the femoral neck are approximately equal. In modern humans, the superior cortex is thinner than the inferior cortex by a ratio of approximately one to four. The ratio in this femur (BR1002’00) is one to three. This ratio was subsequently regarded as evidence for transition to an upright posture and habitual bipedal gait.
Although Orrorin was an alleged biped, “the morphology of its humeral shaft and the curvature of the manual phalanx, reveal that it was probably also capable of climbing trees, as were australopithecines.”[15] It is therefore likely that Orrorin was just an arboreal ape-like creature.
Pickford et al. wrote, “We infer that Orrorin was orthograde, even though we have no evidence of the sacrum or lower back.”[16] As previously noted, there was a painful lack of cranial material. It would consequently be impossible to examine the inner ear structures associated with balance and posture. In addition, the absence of sacral, lumbar and pelvic remains made it difficult for experts to reach a consensus regarding Orrorin’s bipedal ability. With such fragmentary evidence, it is of little wonder that only an inference was made concerning orthograde posture.
Finally, they concluded, “that Orrorin was a habitual biped as shown by a suite of features in the proximal femur: moderate intertrochanteric line associated with a weak femoral tubercle, a large gluteal tuberosity and the osseous structure distal to this tuberosity, a precursor of the linea aspera, a shallow trochanteric fossa, the presence of a groove for the obturator externus, the distribution of cortex in the femoral neck, the sectional shape of the femoral neck, the size of the femoral head relative to shaft diameter, the orientation of femoral head on the neck, and the shallowness of the superior femoral notch.”[17]
It is apparent that much of the data is equivocal and does not provide sufficient support for obligate bipedalism. For example, the presence of an obturator externus groove was presented as support. However, the evidence for bipedalism with the presence or lack of obturator externus grooves is not particularly conclusive. Anatomical features that can be used as unequivocal evidence of bipedalism are not available due to the lack of a distal femur, proximal tibia, and the missing greater trochanter. The attempted interpretation of bipedalism based on current fossil material is premature and unclear.
Neo-Darwinists must contend with the question of whether there is a valid genetic mechanism for the evolution of bipedalism. The difficulties encountered encompass much more than mere morphological considerations. The problems in the evolution of femoral neck cortical thickness would lead us to a few genetic considerations. As noted by Lovejoy et al.,[18] one of the more significant recent advances was the elucidation of differences between bone modeling and its subsequent remodeling (Martin et al. 1998).[19] With regard to modeling, many features of external bone morphology have been shown to be governed by systems of genes that act sequentially during ontogeny.[20] As far as remodeling is concerned, features such as bone density now are known to be subject to genetic regulation.[21] The genetic milieu involved is extremely vast and complicated.
The fundamental problem with Orrorin is the a priori assumption that is it biogenetically possible for a quadruped to evolve into a biped. Neo-Darwinism must account for an increase in genetic information via mutations and natural selection. Information theory has shown that it is impossible to increase genetic information “through a series of small steps of microevolution. Mutations needed for these small steps have never been observed. By far, most observed mutations have been harmful to the organism. … … Not even one mutation has been observed that adds a little information to the genome. That surely shows that there are not the millions upon millions of potential mutations the (Neo-Darwinism) theory demands.”[22]
Bipedalism, a defining trait for humanity, appeared suddenly and coincidentally with the hominids’ first appearance. It was agreed that Orrorin lived in a wooded environment, not open savannas.[23] But the evolutionary model has maintained that bipedalism arose gradually when hominids were forced from a forested environment into an open savanna.[24] It is thus apparent that bipedalism emerged in the absence of an evolutionary driving force. Furthermore, the explosive diversity and sudden emergence of bipedalism that accompanied the hominids’ first appearance in the fossil record serve as hallmarks of creation.[25]
Apes who lived 5 or 6 “million years ago” (on the evolutionist’s time line) so resembled each other that we may never know which begat chimp and which begat man. Complicating things even more, the human family tree is so bushy that “there is not a single line from ape to angel,” says anthropologist Donald Johanson, director of the Institute of Human Origins.[26]
So fierce is the controversy over the identity of the oldest human evolutionary ancestor that Martin Pickford sued famed paleoanthropologist Richard Leakey for false arrest when he was jailed in Kenya for supposedly collecting fossils without a permit. He even subtitled a book about Leakey’s “Master of Deceit.”[27] The muddle surrounding Orrorin shatters the myth that the theory of human evolution is one of sober, objective science. It is actually a chaotic potpourri of backbiting, contradictions, and failed “missing links” that receive much ballyhoo before eventually being discarded as evolutionary dead ends.
From a paltry pile of questionable bone fragments, it is extremely doubtful that Orrorin can resurrect the hope of a missing link.
Footnotes
1. M. Pickford and B. Senut, Comptes Rendus de l'Académie des Sciences 332 (2001):145–152
3. Robin McKie, “First humans learnt to walk while living in trees,” observer.co.uk, November 18, 2001. Available from http://www.versiontech.com/origins/news/news_article.asp?news_id=18; Internet; accessed 09 Dec 2004.
4. M. Pickford et al., “Bipedalism in Orrorin tugenensis revealed by its femora,” C. R. Palevol 1 (2002): 202. Académie des sciences / Éditions scientifiques et médicales Elsevier SAS
5. M. Balter, “Early Hominid Sows Division,” Science Now (22 February 2001).
6. Ibid. This contains references to their denials published in Science and photographs of the fossils.
7. “Bright Future for the Human Past” [article on-line]; available from http://www.leakeyfoundation.org/newsandevents/n3.jsp?id=152; Internet; accessed 09 October 2004.
8. M. Balter, “Paleoanthropology: Scientists Spar Over Claims of Earliest Human Ancestor,” Science 291 (2001): 1460-1461
9. Ibid
10. Ibid
11. Ibid
12. Ibid
13. Pickford, “Bipedalism in Orrorin tugenensis revealed by its femora,” 201.
14. Sven Prevrhal, Julia C. Fox, John A. Shepherd and Harry K. Genant, “Accuracy of CT-based thickness measurement of thin structures: Modeling of limited spatial resolution in all three dimensions,” Medical Physics 30, no. 1 (2003): 1-8
15. Pickford, “Bipedalism in Orrorin tugenensis revealed by its femora,” 202.
16. Ibid
17. Ibid
18. C. O. Lovejoy, R. S. Menidl, J. C. Ohman, K. G. Heiple, and T. D. White, “The Maka femur and its bearing on the antiquity of human walking: Applying contemporary concepts of morphogenesis to the human fossil record,” American Journal of Physical Anthropology 119 (2002): 97-133.
19. R. B. Martin, “Toward a unifying theory of bone remodeling,” Bone 26 (1998):1-6.
20. See Carroll S. J. K. Grenier, and S. D. Weatherbee, From DNA to Diversity: Molecular Genetics and the Evolution of Animal Design (Malden, MA: Blackwell Science, 2001).
21. W. G. Beamer, L. R. Donahue, C. J. Rosen, and D. J. Baylink, “Genetic variability of bone density among inbred strains of mice,” Bone 18 (1996): 397-403.
22. Lee Spetner, Not by chance: shattering the modern theory of evolution (New York: The Judaica Press, 1998), 159-160.
23. Patrick Vignaud et al., “Geology and Paleontology of the Upper Miocene Toros-Menalla Hominid Locality, Chad,” Nature 418 (2002): 152-55.
24. Roger Lewin, Principles of Human Evolution (Malden, MA: Blackwell Science, 1998), 219-229.
25. Fazale R. Rana, “The Leap to Two Feet: The Sudden Appearance of Bipedalism,” Facts for Faith 7 (2001): 33-41.
26. S. Begley, “Bickering over Old Bones,” Newsweek [international edition], 23 July 2001.
27. Ibid, 52
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