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between bull and pug-dogs. These changes, as seen in
the pigs, are due to changed conditions and habits of life,
to abundance of food, to the cessation of those activities
on which the wild pig depends for its preservation—
perhaps the phenomenon is enhanced by the principle of
correlated growth and other influences. We have instances
of similar modifications which take place in nature, as for
example, the bull-dog codfish and the “ monstrous breed”
of cattle known as niatas or natas. If we argue from the
case of the improved pig, we may infer that an abundant
source of food in the shape of luxuriant pasturage was
the cause of this transformation in nature, as it is one of
the conditions of such change in art. But if this is so,
we can go a step further, for in the Sivatherium giganteum
of the Pliocene Sivalik Hills of North-eastern India we
have an animal with a similar configuration of facial bones.
In one case, at any rate, we have evidence which goes
to show that the change could not be brought about by
Natural Selection. One of the strongest arguments in
favour of Organic Evolution is based upon the evolution
of the horse, as revealed in successive strata of the earth’s
surface. The change from a five-fingered to a one-fingered
manus is generally selected for special observation. I am
not quite sure that it would be possible to show that the
change, made gradually, would have been a matter of life
and death to the differently endowed individuals ; but un
less we can prove this, or give good reasons for supposing
that this has been so, we have no right to attribute the
change to Natural Selection. It may, however, be observed
that concurrently with this modification of the manus,
there has been a development of the teeth. On this latter
point, Mr. Henry Fairfild Osborn says :—
i! The teeth . . . furnish not only the most intricate correlations
and readjustments, but the complete history of the addition of a