Re: Him and Her

"alwaysaskingquestions" <alwaysaskingquestions@xxxxxxxxx>
wrote in message news:4hsr09F1507dU1@xxxxxxxxxxxxxxxxx
"mel turner" <mturner@xxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:e9b8bp$g24$2@xxxxxxxxxxxxxxxxxxxxxxxx

Then you see incorrectly.

I've already accepted that correction.

Okay. Sorry if I may have seemed snippy about it.

What do you think you're getting at? I suspect you're alluding to the
mistaken notion sometimes seen here that a new species will arise as a
single mutant individual that has to find a similarly changed mate in
order to reproduce. It's wrong, and pretty silly.

No, that's not what I'm trying to get at, see my reply to Ernest

Okay. Sorry I leaped to an incorrect assumption and answered the wrong
question [although there have been past instances of people going
there from similar initial questions to yours].

Your actual question about sexual dimorphism touches on an interesting
area. Across the animal kingdom there are lots of variations and some
interesting extremes. Some generalizations about dimorphism and mating
behavior and competition for mates can be made: In species where males
tend to physically fight one another for access to females, males tend
to be larger and stronger than the females. Species where a few
dominant males have "harems" of many females tend to have much more
dimorphism compared to monogamous species. Extreme examples of this
are things like elephant seals, where the few huge dominant bulls have
exclusive rights to large harems of the much smaller females. They
spend the breeding season fighting off rival males and mating. In
species where the competition for mates isn't all about physical struggle
and feats of strength, males may be similar in size to or smaller than
females. Males are tiny compared to females in some groups, such as
many spiders. Even more extreme are species which have "dwarf males"
that may be attached to or dependent on the female. An extreme case in
vertebrates involve some deep-sea angler fish in which the tiny males
attach to and actually fuse with the much larger female so that they
become small parasitic appendages of the female's body.

There are some suggestions that dimorphism may sometimes involve a
division of labor between members of a pair or at least decreased
competition between males and females [e.g. in some snakes and birds
of prey where smaller males may feed on smaller prey than the females].

cheers



.

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