ly sucking
a drop of scarcely nutritious fluid from an accidentally hypertrophied
cutaneous gland of its mother? And even if one was so, what chance was
there of the perpetuation of such a variation? On the hypothesis of Natural
Selection itself, we must assume that up to that time the race had been
well adapted to the surrounding conditions; the temporary and accidental
trial and change of conditions, which caused the so-sucking young one to be
the "fittest to survive" under the supposed circumstances, would soon cease
to act, and then the progeny of the mother, with the accidentally
hypertrophied, sebaceous glands, would have no tendency to survive the {48}
far outnumbering descendants of the normal ancestral form. If, on the other
hand, we assume the change of conditions not to have been temporary but
permanent, and also assume that this permanent change of conditions was
accidentally synchronous with the change of structure, we have a
coincidence of very remote probability indeed. But if, again, we accept the
presence of some harmonizing law simultaneously determining the two
changes, or connecting the second with the first by causation, then, of
course, we remove the accidental character of the coincidence.

Again, how explain the external position of the male sexual glands in
certain mammals? The utility of the modification, when accomplished, is
problematical enough, and no less so the incipient stages of the descent.

As was said in the first chapter, Mr. Darwin explains the brilliant plumage
of the peacock or the humming-bird by the action of sexual selection: the
more and more brilliant males being selected by the females (which are thus
attracted) to become the fathers of the next generation, to which
generation they tend to communicate their own bright nuptial vesture. But
there are peculiarities of colour and of form which it is exceedingly
difficult to account for by any such action. Thus, amongst apes, the female
is notoriously weaker, and is armed with much less powerful canine tusks
than the male. When we consider what is known of the emotional nature of
these animals, and the periodicity of its intensification, it is hardly
credible that a female would often risk life or limb through her admiration
of a trifling shade of colour, or an infinitesimally greater though
irresistibly fascinating degree of wartiness.[38]

{49}
[Illustrati