Human evolution: no hominin ancestor (Introduction)

by David Turell , Thursday, October 27, 2022, 17:20 (544 days ago) @ David Turell

Current fossils refuted:

https://evolutionnews.org/2022/10/the-standard-story-of-human-evolution-a-critical-look/

"[T]he evolutionary sequence for the majority of hominin lineages is unknown. Most hominin taxa, particularly early hominins, have no obvious ancestors, and in most cases ancestor-descendant sequences (fossil time series) cannot be reliably constructed.

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"Although Sahelanthropus tchadensis (also known as the Toumai skull) is known only from one skull and some jaw fragments, it has been called the oldest-known hominin on the human line. When first published, articles in the journal Nature called it “the earliest known hominid ancestor” and “close to the last common ancestor of humans and chimpanzees”; as of 2020, the Smithsonian Institution still called it “one of the oldest known species in the human family tree.”

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"In 2020, nearly two decades after the fossil was first reported, the debate was seemingly settled when the femur of Sahelanthropus was finally described, confirming that it was a quadruped with a chimp-like body plan. This evidence forced the researchers to suggest that if Sahelanthropus were a human ancestor, then that would mean bipedality is no longer a necessary qualification for status as a hominid — an unorthodox view that would wreak havoc with the primate tree. More likely is the view of Madelaine Böhme at the University of Tübingen in Germany: “itʼs more similar to a chimp than to any other hominin,” meaning, as another commentator put it, Sahelanthropus “was not a hominin, and thus was not the earliest known human ancestor.”

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"Paleoanthropologists initially claimed Orrorin’s femur indicates bipedal locomotion “appropriate for a population standing at the dawn of the human lineage,”15 but a later Yale University Press commentary admitted, “All in all, there is currently precious little evidence bearing on how Orrorin [tugenensis] moved.”

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"In 2009, Science announced the long-awaited publication of details about Ardipithecus ramidus (pictured above), a would-be hominin fossil that lived about 4.4 million years ago (mya). Expectations mounted after its discoverer, UC Berkeley paleoanthropologist Tim White, promised a “phenomenal individual” that would be the “Rosetta stone for understanding bipedalism.”

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"As the authors of the Nature article stated, Ardi’s “being a human ancestor is by no means the simplest, or most parsimonious explanation.”29Sarmiento even observed that Ardi had characteristics different from both humans and African apes, such as its unfused jaw joint, which ought to remove her far from human ancestry.30

"Whatever Ardi was, everyone agrees the fossils was initially badly crushed and needed extensive reconstruction. No doubt this debate will continue, but are we obligated to accept the “human ancestor” position promoted by Ardi’s discoverers in the media? Sarmiento doesn’t think so. According Time magazine, he “regards the hype around Ardi to have been overblown.

Comment: there is a major fossil gap for pre-hominin forms. It is not a Cambrian gap. We simply don't have enough fossils found to make believable series. Here I agree with dhw. We need and hope to find more. On the other hand, if Bechly is correct in his view of fossil finding, and what we have is all there is, there would be a Cambrian-like gap.