... The question you seem to lack an answer to is why we should think it was so uniquely important in shaping these human traits and why we should think that your answer of sexual selection is more compelling than the alternative hypotheses.
But it's not just sexual selection -- it's runaway sexual selection. That is what drives selected traits in a direction that comes up against the limits of variation in the population, traits that are exaggerated in the individuals compared to other species, especially close cousins like the chimpanzees and bonobos.
We look at text-book examples of runaway sexual selection -- peacocks and scissor-tail flycatchers -- and we see selected traits driven in a direction that comes up against the limits of variation in the population, traits that are exaggerated in the individuals compared to other species, and recognize it for what it is: fisherian run-away sexual selection.
As stated in
Message 1:
quote:
The identifying characteristics of run-away sexual selection, then, that differentiate it from normal sexual selection, involve a feature (or features) carried to an extreme that is not needed for species survival (and which may even jeopardize survival), and that may still be selected for if it were possible to undergo further (still continuing?) evolution.
This would be evident in a skewing of the population chosen for mates versus the variation within the population (demonstrating that it is one extreme end of available variations that is consistently chosen), and it would also be evident in comparison to closely related cousins without the features (demonstrating that the features are not needed for survival): all the longer tailed male birds mated, and close cousins do not have a long tail.
That doesn't make us "special" when we see similar extreme trait selection and development, it just explains how we got to where we are with those traits.
If you have a better explanation then trot it out and let's see how it compares.
Enjoy.
Edited by RAZD, : msg1 ref
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