[RWebb]

What is "obvious" to the inexpert is usually just prejudice - that is why scientists & engineers do research - sorta like why people actually play football games instead of sitting in a comfy chair and pontificating.

alf - the study shows there is a selection gradient

if there are genetic characters associated with the effects, then yes they will be passed on

there probably ARE such genetic characters in humans - an interesting question would be if they are selected for during certain periods of civilization and not in others