Bruce Quinn (quinn at is2.nyu.edu) wrote:
} One theory was that it goes with the dominant hand, which is right,
} hence the left hemiphere gets language. Another, that left and right
} hands were differentiated for tree climbing.
Look- you have to explain why one side gets a species preference.
The tree climbing theory sounds like bullshit to me. I can plane a piece
of wood both ways, but I cannot use a knife with my right. But why do
97% of manking prefer the right for knife work?
Look for the reason in something that is really important to spread
over a lot of area in the brain, then find out what connection was not
compatible with coping in society and was deselected. Right-turning and
left-turning rats are eqwually abundandt, why not right-handed and
left-handed humans?
} A physical explanation would be assymetry of blood flow in the left
} and right carotid arteries, since the heart and aorta are assymetric.
} This sets up one hemisphere to be slightly different than the other.
That is a good idea. There is asymmetry in structure; why is situs
inversus totalis so scarce? Read J P Changeux on this one, if ever he
wrote anything in English.
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