Human evolution: Big eyes is latest speculation as to why Neanderthals went extinct

Skinning a carcass

According to a recent BBC science article, new research shows that Neanderthals’ large eyes caused their demise (because “As a result, more of their brains were devoted to seeing in the long, dark nights in Europe, at the expense of high-level processing.”)

It’s a tough market out there for speculation on why the Neanderthals are no longer with us. Here’s most of the current field:

Some say we crowded them out. Others say that they disappeared due to intermarriage with modern humans. No wait, they died before we got to them. This just in: They were victims of an early industrial revolution. And just think, they kept us alive, but it didn’t do them much good.

Some researchers ignore the eyes, noting that Neanderthals had weaker Achilles tendons, and therefore running ability lagged, which “hits at the crux of why Neanderthals went extinct.”

Another whole line of research changes the story altogether: They disappeared when they intermarried with modern humans [1]. Or maybe not. Or just ships passing in the night. With few children.

In short, as paleoanthropologist Tim White says,

Two new fossil jawbones from Kenya are claimed to confirm a diversity of early Homo species. However, archaic species concepts and an inadequate fossil record continue to obscure the origins of our genus.

He doesn’t mention the problem of too many speculations chasing two few facts, but that is a problem too.

See also: Human evolution: What use are grandmothers?

[1] Michael Marshall, “Breeding with Neanderthals helped humans go global,” New Scientist, 16 June 2011: http://tinyurl.com/3tznlo8 ; “Non-Africans Are Part Neanderthal, Genetic Research Shows,” ScienceDaily, July 17, 2011: http://tinyurl.com/3r855zt ; See also Mason Liang and Rasmus Neilsen, “Q&A: Who is H. sapiens really, and how do we know?”, BMC Biology 2011: http://tinyurl.com/3fjasa7 ; “Ancient humans were mixing it up,” Eurekalert, September 2, 2011: http://tinyurl.com/3oolhe4

Denyse O’Leary is co-author of The Spiritual Brain.