Re: Breast Size (Was: Re: Homosexuality and genetic determinism)

Paul Bernhardt (
31 May 1995 08:05:33 GMT

Tim Benham ( wrote:
: Michael Andrew Turton ( wrote:
: : In article <3q7g9h$>, Bryant <> wrote:
: ...
: : He DID present a group selectionist argument. Male attraction to
: : large breasts (if indeed it innately exists) came after they arrived on the
: : evolutionary scene -- BIG BREASTS CAME FIRST.

: I'm curious to know what evidence you have for this statement. Since
: you refuse to admit a role for sexual selection at all, you need a
: period of evolution when women's breasts got bigger and men's
: preferences didn't change followed by one in which men's preferences
: changed and women's breasts didn't. This seems very implausible, but I
: may change my mind when I see your evidence.

: ....

I proposed an explanation, though not 'evidence', for this kind of
process some weeks back.

Upright walking narrows the birth canal. The narrowed birth canal
necessitates an underdeveloped infant, particularly the brain (the head
is the largest part of the infant). Brain development is especially
dependent on a consistant and extremely high fat diet (particularly for
mylination of the nervous system). Larger breasts therefore are a likely
consequence of upright walking (itself necessary due to the hypothesized
decrease in trees on the plains of east Africa about the time of human
development.) Larger breasts may become a direct cue for men of fitness to
raise children. Furthermore, large breasts may be a reminder of the
buttocks, itself a sexual cue. Breasts may then become even larger
because men, in seeing the faux sexual cue of the large breasts, might
attempt intercourse with larger breasted women causing selection pressure
for breasts larger than necessary for the care of a child.

By the way, I don't see all facets of women to be simply there to please
or entice men. It should all be based on selection. First, left over
parts are things that done lead to failure to survive (not selected
against). Second, existing parts are enhanced, though not necessarily
optimally, through pressures that favor their selection.