On order from Amazon. Sounds interesting and I need to read it, if only for professional reasons. Taylor apparently cites the reduction of lactose intolerance in humans as an example of technology bringing about evolutionary change. Originally, when weaned, the ability to process milk in humans was “switched off” as it was no longer needed. In other words, nearly all adults were lactose intolerant. But with the “secondary products revolution” that followed the Neolithic adoption of agriculture, milk became a useful food source; lactose intolerance became a disadvantage and was selected against.
However, one ”pet” example of such change (I DON’T know if this is in Taylor’s book) has now been shown to be dubious - the change from large ape-like guts in the australopithecines to the smaller guts of humans came about through tool use, enabling humans to butcher carcasses and switch to a meat-based diet. Smaller, less energy-expensive guts were required for this higher quality diet, opening up the way for our large, gas-guzzling brains.
But: australopithecines (not just late ones like A. garhi) may have used tools (McPherron et al, 2010), and probably didn’t have large guts (Haile Selassi, 2010). Both discoveries are very recent, but the inclusion of meat in the australopithecine diet and implied tool use has been suspected for over a decade (Sponheimer & Lee-Thorp, 1999; Teaford & Ungar, 2000).
The trouble with writing in this field is that it is VERY easy to be out of date!
1 comment:
Lee-Thorp et als work is excellent, and I am delighted the new Nature paper on australopithecine meat eating and expedient tool use has come out now, since I wrote the book; it strengthens the argument I make about the significance of entailed technology at 2.6 ma . . . etc. But I hope you'll read the book. My website (TimothyTaylor.org will be up v shortly, and I will try to tackle issues there)
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