Thursday, July 31, 2014

BioLogos, Ken Ham and David Menton—A Response, Part VI: The Conclusion

This concludes my response to David Menton's post on human origins, which has been a chore to read and respond to. Menton's conclusion is so short, I will post it in its entirety:
Why then are there continued efforts to make apes out of man and man out of apes? In one of the most remarkably frank and candid assessments of the whole subject and the methodology of paleoanthropology, Dr. David Pilbeam (a distinguished professor of anthropology) suggested the following:

Perhaps generations of students of human evolution, including myself, have been flailing about in the dark; that our data base is too sparse, too slippery, for it to be able to mold our theories. Rather the theories are more statements about us and ideology than about the past. Paleoanthropology reveals more about how humans view themselves than it does about how humans came about. But that is heresy.
Oh, that these heretical words were printed as a warning on every textbook, magazine, newspaper article, and statue that presumes to deal with the bestial origin of man!
No, we are not descended from apes. Rather, God created man as the crown of His creation on Day 6. We are a special creation of God, made in His image, to bring Him glory. What a revolution this truth would make if our evolutionized culture truly understood it!
First, David Pilbeam wrote that almost forty years ago, and yet Menton appears to hold it up as current scholarship.  You wouldn't do that in any legitimate scientific discipline.  It may be a good example of “look what we thought back then,” in a historical sense and as compare and contrast but not current thought.  This is a typical young earth creationist tactic: find a useful quote and keep using it, long after it is no longer true or has been debunked.  As such, it is no different than using (or abusing) Solly Zuckerman's quote from the early 1970s.  I saw Duane Gish at the University of Tennessee a few years back he used Zuckerman's quote as well.  Once a quote is found, it makes the rounds.

Pilbeam's quote comes from a review of Richard Leakey's book Origins and is found in the American Scientist (Vol. 66, No. 3, May-June 1978).  Let's see what Pilbeam thinks about palaeoanthropology as of 1995:
The discovery of an australopithecine mandible together with a middle Pliocene fauna 2,500 km west of the Rift Valley considerably extends the known range of these early hominids and raises several interesting issues. The Chad specimen is most similar to its East African contemporary A. afarensis. Nevertheless, in certain features-mandibular morphology, premolar roots and enamel thickness- it differs from the described hypodigm of A. afarensis . Given the genetic and morphological differences now recognized between allopatric populations within, for example, Pan troglodytes, Gorilla gorilla, Pongo pygmaeus and Papio hamadryas as well as other African mammals, it is not surprising that contemporaneous hominid populations as geographically distant as Chad and Ethiopia, Kenya and Tanzania would differ in morphology, regardless of whether they are classified as species or subspecies. Here we do not choose to name a new species, recognizing that more detailed comparisons are necessary before the taxonomy of this Bahr el Ghazal hominid can be resolved.1
Here, he and the other authors of the paper clearly feel that the state of the discipline is sound enough to make educated pronouncements about the fossil record.  In all of Pilbeam's papers, it is clear that he is committed “evolutionist.” As with all palaeoanthropologists, he accepts that there may be aspects of the study that are not known or poorly understood but, of the central tenet: that humans have evolved, there is clearly no doubt.  Thirty six years is a long time in the history of a scientific discipline.

How good is our understanding of the human fossil record now?  Here is what another distinguished professor of anthropology, Richard Klein, has to say:
In the absence of fossils, Darwin could not have predicted the fundamental pattern of human evolution, but his evolutionary theory readily accommodates the pattern we now recognize. Probably the most fundamental finding is that the australopithecines, who existed from at least 4.5 million to 2 million years ago, were distinguished from apes primarily by anatomical specializations for habitual bipedalism, and it was only after 2 million years ago that people began to acquire the other traits, including our unusually large brains, that readily distinguish us from the living apes. The greatly expanded fossil record shows that the australopithecines comprised multiple species, and it suggests that our own genus, Homo, descended from one of these about 2.5 million years ago.2
Note the phrase “the greatly expanded fossil record.” Recall the two compendia on this fossil record I mentioned in the first part of this response. Menton clearly is unfamiliar with this record and his attempts to discredit it are shallow, as a result.

To recap:
  • He claims that “evolutionists” just accept similarities between fossil bones of living men and fossilized apes as evidence of ancestry. Such a statement betrays a lack of understanding of homology, functional morphology and the modern study of evolutionary systematics. It glosses over important skeletal structures that arose during our ancestry and which separate our direct ancestors from all apes, fossil or otherwise.
  • He massively under-emphasizes the size of the human fossil record and the complexity of it, simply dismissing it with no examination or explanation.
  • He suggests that research projects cannot be undertaken based on pictures and measurements of fossil hominins.  This is absurd.  There is no scientific discipline that does not rely on published reports.  Moreover, this is a peculiar statement coming from a professor of anatomy, who must have, during his tenure as a professor, read countless articles on aspects of anatomy in which there were published measurements and pictures.  What was he to make of those?  Did they not constitute real research on which he based his own?
  • He mistakenly calls a spider monkey an ape, bringing into question his understanding of basic primate taxonomy.  Further, while his anatomical specialty seems to have been at the cellular level, he betrays a peculiar lack of understanding of human morphological functional interrelatedness by suggesting that the carrying angle of hominins can be dissociated from hip, limb and cranial morphology.  While it may be true that some apes have a similar carrying angle to humans, not a one of them has a foramen magnum at the base of the skull, angled femoral condyles, or a flat, wide pelvis.  Further, these derived traits show up in the fossil record around 3.7 million years ago.  How did he miss these things?  When I took gross anatomy and physiology, I was required to learn not just developmental biology, but functional and comparative morphology.  Has he forgotten his?
  • He writes that Ardipithecus, Orrorin, Sahelanthropus, and Kenyanthropus all have “obviously ape skulls, ape pelvises, and ape hands and feet” despite the fact that only one of these finds preserves the skeletal parts he references. This suggests that he never even bothered to look at the reports detailing these finds.  To make such errant, blanket statements about them is incompetent and sloppy. 
  • He cherry-picks quotes that support his position and ignores ones that do not.  While he calls A. afarensis “long-armed knuckle-walkers” and suggests that palaeoanthropologists Stern and Susman3 argue that it is an ape, he carefully ignores other paragraphs from their article, in which they clearly argue that it is transitional between apes and humans, even using the phrase “missing link.”  He then (again, oddly for an anatomist) ignores other critical morphology of A. afarensis that clearly indicates its transitional status.
  • He writes that Neandertals were considered human but have recently been denigrated to non-human status, when in fact, that is precisely backwards.  From their initial discoveries, Neandertals were considered subhuman4,5 and it has only been within the last thirty years that their relationship to modern humans has been reassessed, inviting claims by some that they represent simply an earlier version of us and incorporating new genetic knowledge of interbreeding between Neandertals and modern humans6.  
  • Despite Menton's attempts to paint Neandertal/modern human genetic differences as small, they are, in fact, significant enough such that Krings et al.7 made the front pages of the journal Cell, arguing that Neandertals were “not our ancestors.”  Even now, with the advent of evidence of hybridization, the prevailing opinion among palaeoanthropologists is that Neandertals are not within the taxon Homo sapiens sapiens but represent a sister taxon (like the Denisovans, who he ignores completely) with which we had genetic contact. 
This is a badly written post that shows little in the way of actual research.  He seems to misunderstand basic anatomy, gets fossil descriptions wrong, quote-mines to show only what appears to support his position and seems to show no understanding of basic evolutionary biology.  His demeanor is pompous and contemptuous and his treatment of the subject matter invites scorn.

I have absolutely no doubt that Dr. Menton is a bible-believing Christian and that, as such, he is an asset to the kingdom.  I also believe that, like so many other young-earth creationists I am familiar with, he treats the fossil material and the discipline of evolutionary biology with dishonesty and lack of integrity.  This saddens me since it, as with all of creation, reflects the goodness, glory and, importantly, the awesomeness of God.  Further, it is a bad witness and pushes people away from God. 
    1Brunet, M, Beauvilain, A, Coppens, Y, Heintz, E, Moutaye, A, Pilbeam, D. (2014) The first australopithecine 2,500 kilometres west of the Rift Valley (Chad). Nature 378, November 16, 1995
    2Klein, R. G. (2009). Darwin and the recent African origin of modern humans. Proceedings of the National Academy of Sciences, 106(38), 16007-16009.
    3Stern Jr, J. T., & Susman, R. L. (1983). The locomotor anatomy of Australopithecus afarensis. American Journal of Physical Anthropology, 60(3), 279-317.
    4Boule, M. (1913). L'homme fossile de La Chapelle-aux-Saints: Masson.
    5Virchow, Rudolf. Untersuchung der Neanderthal Schädels. 1872.
    6For example: Sankararaman S, Patterson N, Li H, Pääbo S, Reich D (2012) The Date of Interbreeding between Neandertals and Modern Humans. PLoS Genet 8(10): e1002947. doi:10.1371/journal.pgen.1002947
    7Krings, M., Stone, A., Schmitz, R. W., Krainitzki, H., Stoneking, M., & Pääbo, S. (1997). Neandertal DNA sequences and the origin of modern humans. Cell, 90(1), 19-30.

    2 comments:

    1. Thanks for your work on this series of posts. Very helpful.

      ReplyDelete
    2. You are welcome. It was painful, trying, maddening and necessary, if nothing else, for catharsis.

      ReplyDelete