I understand and pretty much agree with what Ian wrote. I was intrigued with
"As a somewhat facile rule of thumb though, the more brightly coloured a
male is relative to his mate, the more socially useless he is". If that is
comparing values of males to females, yes. I will take that a different way
from the point Ian was making to compare males to males. To that I would add
the contrasting thought that in a huge range of types of animals of the
highly polygynous (that form of polygamy) species that he is referring to,
what usually happens is that the male that impresses the most females gets
most of the matings and so on average contributes more to the next
generation. In many mammals it drive evolution to the bizarre fighting
systems of many deer and Elephant Seals for example. In birds this is often
in some way the more brightly coloured males. So the more brightly coloured
males being the ones that contribute more to the next generation, they are
the more socially useful and they drive the outlandish features we see in
things like male birds of paradise. Sadly for the males that are less
impressive in the sexual selection stakes, as it is they who are the less
socially useful.
Philip
-----Original Message-----
From: Ian Fraser
Sent: Saturday, 21 July 2012 5:46 PM
Cc:
Subject: bedlam (briefly) at Hawker ovals
Thanks Ray. This is a biggie - ie good question! There is no simple
answer overarching answer, but in any case I'm not really convinced by
the question; if you start going through familiar species you'll
probably think of more cases where sexes are the same or nearly so than
where they're not (and even a very few examples, such as button-quails
and painted snipe, where the female is the gaudy one). As a somewhat
facile rule of thumb though, the more brightly coloured a male is
relative to his mate, the more socially useless he is - although a good
case could be made for the social value of being conspicuous and being
eaten, rather than letting it happen to the more modestly attired female
sitting on the nest. This is overly simple of course, and there's a lot
more to it, but I'm sure things are already occurring to you!
cheers
Ian
On 21/07/2012 17:34, Sue-Ellen and Ray wrote:
> Ian - Thanks for info, most interesting. I have not researched this
> area but sounds like others have with some very specific results. You
> have started me wondering now why,typically, the male birds have the
> brighter colours. I am sure there is a one liner there somewhere.
>
> Ray
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