Re: Human Language (Long)
ailak@walrus.megabaud.fi
4 Jan 1997 11:21:04 +0200
Thomas Clarke, clarke@longwood.cs.ucf.edu, wrote:
> The same can be said for the peacock's tail, the bird of paradise's ta
> the color of the male cardinal, deer antlers and lots of other strange
> phenotyopic features that are the result only of sexual selection.
'Sexual selection' does not mean that what is selected is limited to
sex or gender. It is only one means to select a couple of other traits.
The peacock's tail is just means to keep apart a couple of related
species whose niches are very close to each other.
These species nest in the ground and have a long time of brooding.
The females have colours which allow them to disappear from sight.
They look very similar, since they live in the same environment.
The males will probably mate with any female who appears in their
harems, so it depends only on the females to make the right choices.
Exaggerated characteristics of the male plumage are means to diminish
errors.
The goal of this selection is not to confirm survival of the male
characteristics, though they, of course, survive as well. The main
importance is to keep together the selected combination of traits
which is necessary to be adapted to the niche in question. Any cross
will be away from the female's species, and will diminish the
survival of the male's characteristics in his species.
Same fits to the other examples which you mentioned. Several birds
in temperate and arctic climates change their plumage just for
breeding time and change back to safer colours after it, but the
peacock is a tropical bird and will probably have a longer breeding
time than these.
Sexual selection is an important part of natural selection, the
latter being often understood as mere 'survival of offspring'. As
if death occurred as soon as the young are out of the nest, and the
whole selection was made by that.
A great hominid hunter has certainly been the object of sexual
selection from the females' side. If he was great because he was
smart, or was able to organize great hunts because he could express
himself better than any other man, we can say that 'only sexual
selection' had a considerable effect in our evolution. (This is
a fictious example, I can not say it happened just like that.)
> Tom Clarke
>
> --
> There are more things in heaven and earth, Horatio,
> Than are dreamt of in your philosophy.
> Hamlet - Shakespeare
--
Aila Korhonen in Finland ailak@walrus.megabaud.fi
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