The evolutionary biologist types say high heels are about the way they
reshape a woman's buttocks, putting them more in the "presentation
position"
configuration.

(Hey, I didn't make this up, I'm just reporting it.)

As for women selecting men by scent - there's experiments that show
females
select histoimmunologically complimentary males by scent, unless
they're on
birth control pills, which makes them choose histoimmunologically
similar
males.  The theory is that birth control hormones mimic pregnancy, and
pregnant females tend to associate with siblings that will help them
raise
their offspring.

When I hear people talking about sexual chemistry, I figure they're
talking
about scent / pheromones.