Newsgroups: sci.bio
Path: utzoo!rising
From: rising@utzoo.uucp (Jim Rising)
Subject: sex
Message-ID: <1988Oct13.142507.6897@utzoo.uucp>
Organization: U of Toronto Zoology
Date: Thu, 13 Oct 88 14:25:07 GMT

I suspect that there has been selection in both human sexes for secondary
sexual characteristics--i.e. neither represented an "undifferentiated"
human.  If there were to be only one sex, however, it would have to be
female (repro. parthenogenetically).  This occurs in some fish (teleosts),
amphibians (salamanders), and lizards (two differnt families), but not
in birds (except rarely in turkeys in captivity?) or mammals.   My
point is that if one sex came before the other, it would have to be
females, but it is unlikely that parthenogenesis is in our ancestry, or
if so, certainly not recently.

--Jim Rising
-- 
Name:   Jim Rising
Mail:   Dept. Zoology, Univ. Toronto
        Toronto, Ontario, Canada    M5S 1A1
UUCP:   {allegra,ihnp4,linus,decvax}!utzoo!rising