mestication, at least during early times, unless of service to
man. From these circumstances the number of domesticated animals has never
been large. With respect to plants, I have shown in the ninth chapter how
their varied uses were probably first discovered, and the early steps in
their cultivation. Man could not have known, when he first domesticated an
animal or plant, whether it would flourish and multiply when transported to
other countries, therefore he could not have been thus influenced in his
choice. We see that the close adaptation of the reindeer and camel to
extremely cold and hot countries has not prevented their domestication.
Still less {406} could man have foreseen whether his animals and plants
would vary in succeeding generations and thus give birth to new races; and
the small capacity of variability in the goose and ass has not prevented
their domestication from the remotest epoch.

With extremely few exceptions, all animals and plants which have been long
domesticated, have varied greatly. It matters not under what climate, or
for what purpose, they are kept, whether as food for man or beast, for
draught or hunting, for clothing or mere pleasure,--under all these
circumstances domesticated animals and plants have varied to a much greater
extent than the forms which in a state of nature are ranked as one species.
Why certain animals and plants have varied more under domestication than
others we do not know, any more than why some are rendered more sterile
than others under changed conditions of life. But we frequently judge of
the amount of variation by the production of numerous and diversified
races, and we can clearly see why in many cases this has not occurred,
namely, because slight successive variations have not been steadily
accumulated; and such variations will never be accumulated when an animal
or plant is not closely observed, or much valued, or kept in large numbers.

The fluctuating, and, as far as we can judge, never-ending variability of
our domesticated productions,--the plasticity of their whole
organisation,--is one of the most important facts which we learn from the
numerous details given in the earlier chapters of this work. Yet
domesticated animals and plants can hardly have been exposed to greater
changes in their conditions than have many natural species during the
incessant geological, geographical, and climatal changes of the whole
world. The former will, however, commonly ha