Just When You Thought It Was Safe To Say Chimps And Humans Share A Common Ancestor

The Red Ape rears it’s ugly head. Here is a lengthy quote from PhysOrg.Com:

Schwartz and Grehan scrutinized the hundreds of physical characteristics often cited as evidence of evolutionary relationships among humans and other great apes-chimps, gorillas, and orangutans-and selected 63 that could be verified as unique within this group (i.e., they do not appear in other primates). Of these features, the analysis found that humans shared 28 unique physical characteristics with orangutans, compared to only two features with chimpanzees, seven with gorillas, and seven with all three apes (chimpanzees, gorillas, and orangutans). Gorillas and chimpanzees shared 11 unique characteristics.

Schwartz and Grehan then examined 56 features uniquely shared among modern humans, fossil hominids-ancestral humans such as
Australopithecus-and fossil apes. They found that orangutans shared eight features with early humans and Australopithecus and seven with Australopithecus alone. The occurrence of orangutan features in Australopithecus contradicts the expectation generated by DNA analysis that ancestral humans should have chimpanzee similarities, Schwartz and Grehan write. Chimpanzees and gorillas were found to share only those features found in all great apes.

Schwartz and Grehan pooled humans, orangutans, and the fossil apes into a new group called “dental hominoids,” named for their similarly thick-enameled teeth. They labeled chimpanzees and gorillas as African apes and wrote in Biogeography that although they are a sister group of dental hominoids, “the African apes are not only less closely related to humans than are orangutans, but also less closely related to humans than are many” fossil apes.

The researchers acknowledge, however, that early human and ape fossils are largely found in Africa, whereas modern orangutans are found in Southeast Asia. To account for the separation, they propose that the last common human-orangutan ancestor migrated between Africa, Europe, and Asia at some point that ended at least 12 million to 13 million years ago. Plant fossils suggest that forests once extended from southern Europe, through Central Asia, and into China prior to the formation of the Himalayas, Schwartz and Grehan write, proposing that the ancestral dental hominoid lived and roamed throughout this vast area; as the Earth’s surface and local ecosystems changed, descendant dental hominoids became geographically isolated from one
another.

This research is being published in the Journal of Biogeography and can be found here (and is open access, so the link opens the pdf)

I haven’t had a chance to read it yet, but here is a cautionary story about dental apes and such (open access as well, so the link opens a pdf).

I haven’t had a chance to read it yet and will have more to say when I have.

About these ads

3 Responses

  1. Combine this data with gene studies and you’ve got yourself a nice case of either convergent evolution, or the newly discovered phenomenon of trait re-expression.

  2. They make some interesting claims that do not seem to be supported by the evidence. I’m still reading it so I will leave it at that until I’m finished.

  3. I also forgot to mention that, last time I checked the supplementary material was not available yet…

Comments are closed.

Follow

Get every new post delivered to your Inbox.

Join 53 other followers

%d bloggers like this: