How Dogs Created Humans … ?

Apr 25 2012 @ 2:34pm

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… and thereby enabled our species to outlast the Neanderthals. Using dogs for hunting almost certainly increased both the efficiency of hunting and the amount of animal meat consumed. Humans with dogs beat out Neanderthals without them. And there's another possible twist in  fascinating piece in American Scientist:

Domestication is a two-way street, as we know from examples such as the genetic changes that make adult humans able to digest milk. Those mutations arose several times in different human populations after the domestication of cattle. I have no evidence that the change I am about to discuss did or did not occur between 45,000 and 35,000 years ago. But it might have. …

DustygazeA study by Hiromi Kobayashi and Shiro Kohshima of the Tokyo Institute of Technology showed that modern humans are unique among extant primates in having highly visible white sclerae surrounding the colored irises of their eyes, as well as eyelids that expose much of the sclerae. In other primates, the dark sclerae, similarly colored skin and concealing eyelids tend to mask the direction in which the animal is looking, according to the Japanese team. In humans, the white sclerae and open eyelids make the direction of a person’s gaze visible from a distance, particularly if that glance is directed in a more or less horizontal direction. The changes in the human eye may be adaptations to enhance the effectiveness of the gaze signal…

Ádám Miklósi of Eötvös Loránd University in Budapest, Hungary, and his team tested dogs and wolves, and found that dogs were far more attentive to human faces than were wolves, even socialized wolves. Although wolves excel at some gaze-following tasks, perhaps suggesting a preadaptation for communicating with humans, dogs tend to look at human faces for cues and wolves do not. Miklósi’s team believes this major behavioral difference is the result of selective breeding during domestication.