ated to prey on insects on the ground; that upland geese, which
never or rarely swim, should have been created with webbed feet; that a
thrush should have been created to dive and feed on sub-aquatic insects;
and that a petrel should have been created with habits and structure
fitting it for the life of an auk or grebe! and so on in endless other
cases. But on the view of each species constantly trying to increase in
number, with natural selection always ready to adapt the slowly varying
descendants of each to any unoccupied or ill-occupied place in nature,
these facts cease to be strange, or perhaps might even have been
anticipated.

As natural selection acts by competition, it adapts the inhabitants
of each country only in relation to the degree of perfection of their
associates; so that we need feel no surprise at the inhabitants of
any one country, although on the ordinary view supposed to have been
specially created and adapted for that country, being beaten and
supplanted by the naturalised productions from another land. Nor ought
we to marvel if all the contrivances in nature be not, as far as we can
judge, absolutely perfect; and if some of them be abhorrent to our ideas
of fitness. We need not marvel at the sting of the bee causing the bee's
own death; at drones being produced in such vast numbers for one
single act, and being then slaughtered by their sterile sisters; at the
astonishing waste of pollen by our fir-trees; at the instinctive hatred
of the queen bee for her own fertile daughters; at ichneumonidae feeding
within the live bodies of caterpillars; and at other such cases. The
wonder indeed is, on the theory of natural selection, that more cases of
the want of absolute perfection have not been observed.

The complex and little known laws governing variation are the same, as
far as we can see, with the laws which have governed the production of
so-called specific forms. In both cases physical conditions seem to have
produced but little direct effect; yet when varieties enter any zone,
they occasionally assume some of the characters of the species proper
to that zone. In both varieties and species, use and disuse seem to have
produced some effect; for it is difficult to resist this conclusion
when we look, for instance, at the logger-headed duck, which has wings
incapable of flight, in nearly the same condition as in the domestic
duck; or when we look at the burrowing tucutucu, which is occasionally
bli