reyhound, or as with the game-cock, by breeding
from the victorious birds. So under nature with the nascent giraffe, the
individuals which were the highest browsers and were able during dearths
to reach even an inch or two above the others, will often have been
preserved; for they will have roamed over the whole country in search of
food. That the individuals of the same species often differ slightly
in the relative lengths of all their parts may be seen in many works of
natural history, in which careful measurements are given. These slight
proportional differences, due to the laws of growth and variation, are
not of the slightest use or importance to most species. But it will have
been otherwise with the nascent giraffe, considering its probable habits
of life; for those individuals which had some one part or several parts
of their bodies rather more elongated than usual, would generally
have survived. These will have intercrossed and left offspring, either
inheriting the same bodily peculiarities, or with a tendency to vary
again in the same manner; while the individuals less favoured in the
same respects will have been the most liable to perish.

We here see that there is no need to separate single pairs, as man does,
when he methodically improves a breed: natural selection will preserve
and thus separate all the superior individuals, allowing them freely
to intercross, and will destroy all the inferior individuals. By this
process long-continued, which exactly corresponds with what I have
called unconscious selection by man, combined, no doubt, in a most
important manner with the inherited effects of the increased use of
parts, it seems to me almost certain that an ordinary hoofed quadruped
might be converted into a giraffe.

To this conclusion Mr. Mivart brings forward two objections. One is
that the increased size of the body would obviously require an increased
supply of food, and he considers it as "very problematical whether the
disadvantages thence arising would not, in times of scarcity, more than
counterbalance the advantages." But as the giraffe does actually exist
in large numbers in Africa, and as some of the largest antelopes in the
world, taller than an ox, abound there, why should we doubt that, as
far as size is concerned, intermediate gradations could formerly have
existed there, subjected as now to severe dearths. Assuredly the being
able to reach, at each stage of increased size, to a supply of foo