Geo. Indeed, it is not so obvious, but can and does happen about 25% of the time. The clue it the general mechanism is almost apparent in Rook's argument above. But it is not quite completed.


Also, the killing of the weak and and the sick etc. generally is NOT a benefit accrued to a species in an adaptive sense. It requires a group selectionist argument that doesn't stand up to the math.

But right now, I have to solve some paleohuman questions with a student.


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BrentD, (Professor - just for Stan)

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