Thursday, March 12, 2009

Human Footprints Step on the ICR

The ICR has an article called "Ancient Human Footprints Look Modern" by Brian Thomas, who is a science writer. It is part of their "Honoring Charles Darwin: Evolution's Biggest Gaps" series. My first thought when I read the title was: "Yes...and?" He starts out thus:
Some scientists have estimated that sets of human footprints found on two separate but close sedimentary layers in Kenya are around 1.51 and 1.53 million years old1 and were made by humans like the “Turkana Boy,” an anatomically human fossil discovered within the same general area in 1984.2 But do these footprints clarify or confound the standard evolutionary explanations?
The referenced article is out of LiveScience and is called "The Shoe Fits!" The author, Jeremy Hsu, writes:
"We're seeing a very different hominid at this stage," Harris said, pointing to both an increase in size and change in stride during the relatively short time between Australopithecus (the first in this genus lived about 4 million years ago and the last died out between 3 million and 2 million years ago) and Homo erectus. The latter hominids would have been able to travel more quickly and efficiently over larger areas.
Thomas comments on this:
The obvious “humanness” of these footprints highlights the fact that clear distinctions exist between humans and other creatures. LiveScience reported that these prints have “modern foot features such as a rounded heel, a human-like arch and a big toe that sits parallel to other toes…By contrast, apes have more curved fingers and toes made for grasping tree branches.”2 For example, despite museum depictions of the extinct ape Australopithecus having fully human feet, fossils show that they had typical ape feet.3
The story being referenced here is Footprints to Fill, which appeared in the Scientific American news section. Here is the problem: that is not quite what the article states:

To get a toehold on the Laetoli problem, the researchers first compared the gaits of modern humans walking on sand with two sets of the fossil tracks. This analysis confirmed that the ancient footprints were left by individuals who had a striding bipedal gait very much like that of people today. The team then scrutinized naviculars of A. afarensis, H. habilis, chimpanzees and gorillas. The dimensions of the H. habilis navicular fell within the modern human range. In contrast, the A. afarensis bone resembled that of the flat-footed apes, making it improbable that its foot had an arch like our own. As such, the researchers report, A. afarensis almost certainly did not walk like us or, by extension, like the hominids at Laetoli.

But according to bipedalism expert C. Owen Lovejoy of Kent State University, other features of the australopithecine foot, such as a big toe that lines up with, rather than opposes, the other toes, indicate that it did have an arch. Even if it did not, Lovejoy contends, that would not mean A. afarensis was incapable of humanlike walking. "Lots of modern humans are flat-footed," he observes. "They are more prone to injury, because they lack the energy-absorptive capacities of the arch, but they walk in a perfectly normal way."

Thomas has selectively quoted the article to put forth the point that A. afarensis was not an early human because it did not walk like one. This, despite a wealth of fossil material that demonstrates otherwise, including a fully articulated knee joint that shows a bicondylar angle—a trait only known in humans. Thomas end thus:
Despite fossil interpretations that deliberately exclude the historical framework provided by God in the Bible, the evidence stubbornly insists that human evolution never took place, and that people were created fully-formed and fully-functional from the beginning.
Sheer nonsense. The fossil remains from A. afarensis show it to be a perfect transitional fossil. How does Thomas explain the intermediate nature of the palate, the semi-rotated premolar and slight diastema between the canine and premolar and the angular rib cage that are intermediate between the ape and human condition? The answer is probably that he can't because he is unaware of the morphology of this fossil human species. More misinformation from the ICR.

Articles cited:

Hsu, J. The Shoe Fits! 1.5 Million-Year-Old Human Footprints Found. LiveScience. Posted on on February 26, 2009, accessed March 12, 2009.

Wong, K. August 1, 2005. Footprints to Fill: Flat feet and doubts about makers of the Laetoli tracks. Scientific American, 18-19. Accessed March 12, 2009

No comments:

Post a Comment