19 JUL 2013 by ideonexus
Hand Axes as an Extended Phenotype
Two and a half million years ago, our small-brained ancestors
evolved the ability to knock flakes from rocks to use as cutting edges. By doing so, they could also make the rocks themselves useful as choppers. This basic tool kit of flakes and choppers served the needs of hunting and gathering for a million years. Then, around 1.6 million years ago, a medium-brained African hominid (Homo erectus) evolved the ability to produce an extraordinary object that archeologists call a handaxe. A handax...If, as the author assumes, handaxes were genetically-informed because they did not change for hundreds of thousands of years, then why do we not still have the instinct for hand axes?
30 MAY 2012 by ideonexus
"Run the Tape Again"
Run the tape again, and let the tiny twig of Homo sapiens expire in Africa. Other hominids may have stood on the threshold of what we know as human possibilities, but many sensible scenarios would never generate our level of mentality. Run the tape again, and this time Neanderthal perishes in Europe and Homo erectus in Asia (as they did in our world). The sole surviving human stock, Homo erectus in Africa, stumbles along for a while, even prospers, but does not speciate and therefore remains ...We are here by luck, not fate.