these two species is extremely distinct. Therefore the females of
natural species cannot have an unlimited scope for their taste. In the
second place, I presume that no supporter of the principle of sexual
selection believes that the females select particular points of beauty
in the males; they are merely excited or attracted in a greater degree
by one male than by another, and this seems often to depend, especially
with birds, on brilliant colouring. Even man, excepting perhaps an
artist, does not analyse the slight differences in the features of the
woman whom he may admire, on which her beauty depends. The male
mandrill has not only the hinder end of his body, but his face
gorgeously coloured and marked with oblique ridges, a yellow beard, and
other ornaments. We may infer from what we see of the variation of
animals under domestication, that the above several ornaments of the
mandrill were gradually acquired by one individual varying a little in
one way, and another individual in another way. The males which were
the handsomest or the most attractive in any manner to the females
would pair oftenest, and would leave rather more offspring than other
males. The offspring of the former, although variously intercrossed,
would either inherit the peculiarities of their fathers or transmit an
increased tendency to vary in the same manner. Consequently the whole
body of males inhabiting the same country would tend from the effects
of constant intercrossing to become modified almost uniformly, but
sometimes a little more in one character and sometimes in another,
though at an extremely slow rate; all ultimately being thus rendered
more attractive to the females. The process is like that which I have
called unconscious selection by man, and of which I have given several
instances. In one country the inhabitants value a fleet or light dog or
horse, and in another country a heavier and more powerful one; in
neither country is there any selection of individual animals with
lighter or stronger bodies and limbs; nevertheless after a considerable
lapse of time the individuals are found to have been modified in the
desired manner almost uniformly, though differently in each country. In
two absolutely distinct countries inhabited by the same species, the
individuals of which can never during long ages have intermigrated and
intercrossed, and where, moreover, the variations will probably not
have been identically the same, sexual selection might cause the males
to differ. Nor does the belief appear to me altogether fanciful that
two sets of females, surrounded by a very different environment, would
be apt to acquire somewhat different tastes with respect to form,
sound, or colour. However this may be, I have given in my Descent of
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