In others, they just leave it alone, and in
others they elongate the tail by adding feathers to it.
Now the question is, do long-tailed males get the girls?
Well,
indeed, they do.
The number of offspring from these shortened birds are
much, much less than if you elongate the tails.
So there's, there's a real preference and a real drive on, on the part
of selection to, for females, to choose the long-tailed males.
Now, lots and lots of birds, lots of mammals, lots of different
kinds of insects have very exaggerated ornaments.
And there's a reason why some of these may evolve.
And you need to do a lot of experimental work to sometimes sort that out.
So for instance, there could be pleiotropic gene effects.
And what that's saying is that there could be
selection for something else, just let's say, body size.
But, at the same time that you're choosing body size, you may be choosing long tail.
So you're not actually choosing, selection is not choosing
the long tail per se, it's choosing body size.
And pleiotropic gene effect means that different kinds of, of traits may
hitchhike on other traits, selection for
other traits, simply because there's gene effects
affecting both of those kinds of traits.
And we can select for ecological sex differences.
In different situations, we can, one of the most important is male/male contests.
So the males with the gaudiest plumage, let's say sometimes do better in male/male
conflicts for females than, and the big, big elephant seals with their large,
large bodies and big probosses and big bulk.
They get more females in the harem then less aggressive, smaller, smaller males.
Then there's this whole notion that females
are actually choosing the males and there's
a lot of experimental evidence that there's
mating preferences on the part of females.
And if
we look at the, the number of kind of ornaments
that have evolved, and the female preferences for them, we
don't need to go into all of this, but in
the, this one, this one and this one are most important.