Ardi Reveals More Than They Think

Headlines proclaimed a breakthrough in evolutionary evidence due to the discovery of Ardipithecus ramidus, a supposedly bipedal organism earlier than previously thought.  Another "missing link" along the evolutionary chain that explains how human beings came to walk upright.  The timeline of such announcements is becoming familiar.  Soon after the headline follows the detail that offsets the hype and indicates that the initial claims aren't as clear cut as offered.  That is the case with the introduction of Ardi.

Casey Luskin at the Discovery Institute explains.  Ardi was discovered in the early 1990s and has undergone significant reconstructive surgery to the pelvis, which was crushed when found.  Science magazine itself reported this in 2002.  Now that's significant because it's the pelvis that is the primary clue to how a creature moves.  In other words, the headline about Ardi's signficance is an interpretation based on massive reconstruction of a pelvis that was in tiny, little pieces.

Science magazine itself reports doubt about the interpretation that was blared in the headlines.

However, several researchers aren’t so sure about these inferences. Some are skeptical that the crushed pelvis really shows the anatomical details needed to demonstrate bipedality. The pelvis is “suggestive” of bipedality but not conclusive, says paleoanthropologist Carol Ward of the University of Missouri, Columbia.

Luskin explains the bottom line of the discovery even if the inference and the reconstruction are correct:

We already knew of upright walking / tree-climbing, small-brained hominids—that’s what Lucy, an australopithecine, was. We already knew that there were australopithecine fossils dating back to before 4 million years, and this fossil is only a little bit older. So what does this fossil teach us? Assuming all the reconstructions of Ardi's crushed bones are objective and accurate, this fossil teaches us at least one very important thing: prevailing evolutionary explanations about how upright walking supposedly evolved in humans, confidently taught in countless college-level anthropology classes, were basically wrong.

In particular, A. ramidus casts doubt on the long-repeated hypothesis that humans evolved upright walking on the African Savannah where taller creatures had an advantage to see over tall grass by walking upright. A. ramidus walked upright in a “grassy woodland with patches of denser forest.”

A Time magazine article points to this same conclusion.  It is significant in that it indicates that the evolutionary story is an interpretation of the evidence rather than fact itself.  Evolution rests on its explanatory power about the factors that propelled the selection of some species and changes over others.  The reason for selection is the justification for evolution. Evolutionary theory is the explanation.

The fact that Ardi walked upright in a similar environment many hundreds of thousands of years earlier makes it clear that there must have been another reason.

This short sentence from Time is significant because it actually concedes quite a bit.  Ardi, contrary to the headlines, questions standard evolutionary explanation rather than supports it.  Ardi was bipedal (if that is an accurate interpretation of the fossil) in an environment where evolutionary explanation can't explain.

This information is in the Science article.  These facts are in the Time article.  And they undermine the headlines about Ardi.

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Melinda Penner