This is a wonderful time to be studying human origins. Scholars used to think that there was a slow steady progression of one single species after another becoming more and more human-like through time. That’s not the way it was at all. Although these fossils give no evidence for when H. naledi went extinct, it’s clear it was our contemporary in Africa for at least a little while. There also were at least several other hominin species outside of Africa at that same time. Some members of our species migrated out of Africa to Eurasia about 70,000 years ago, only to find that Homo neanderthalensis and the related, but distinctive Denisovans were already there. At the same time, the primitive diminutive species, H. florisiensis, occupied an island in Indonesia, and H. erectus was in eastern Asia. Meanwhile, back in Africa, we know from genetic evidence that, in addition to H. naledi, another unknown hominin species was present and interbred with our species as recently as 30,000 years ago. So our lineage shared life on this planet with a whole set of other species up until just a few thousand generations ago.A bit back, I wrote a BioLogos post where I examined the hominin diversity in the early to middle Pleistocene, in which I asked the question How Many Forms Were There? In that post, I pointed out that our simplistic notions of hominin taxonomy needed to be seriously re-evaluated. Where we once upon a time thought that there was only one species of hominin between 3 and 3.5 million years ago, there may, in fact, have been anywhere from three to five. It is becoming more likely that this is a pattern that characterizes human evolution, perhaps, all the way up to the ascendancy of modern humans. If this is so, then Bernard Wood is correct, in that we have many, many more species throughout the range of human evolution than we thought. This discovery will cause a radical rethink of how we interpret species in the human fossil record. Witness the rise of systematics.
Friday, May 12, 2017
New Post on Homo naledi From Darrel Falk and Deb Haarsma
Darrel Falk and Deb Haarsma have teamed up on a new post about the peculiar South African hominin, Homo naledi, a find on which I reported a few days back. Darrel Falk: