the case of the coadaptations of
organic beings to each other and to their physical conditions of life,
untouched and unexplained.

It is, therefore, of the highest importance to gain a clear insight into
the means of modification and coadaptation. At the commencement of
my observations it seemed to me probable that a careful study of
domesticated animals and of cultivated plants would offer the best
chance of making out this obscure problem. Nor have I been disappointed;
in this and in all other perplexing cases I have invariably found that
our knowledge, imperfect though it be, of variation under domestication,
afforded the best and safest clue. I may venture to express my
conviction of the high value of such studies, although they have been
very commonly neglected by naturalists.

From these considerations, I shall devote the first chapter of this
Abstract to Variation under Domestication. We shall thus see that a
large amount of hereditary modification is at least possible, and, what
is equally or more important, we shall see how great is the power of man
in accumulating by his Selection successive slight variations. I will
then pass on to the variability of species in a state of nature; but
I shall, unfortunately, be compelled to treat this subject far too
briefly, as it can be treated properly only by giving long catalogues of
facts. We shall, however, be enabled to discuss what circumstances
are most favourable to variation. In the next chapter the Struggle
for Existence amongst all organic beings throughout the world, which
inevitably follows from their high geometrical powers of increase, will
be treated of. This is the doctrine of Malthus, applied to the whole
animal and vegetable kingdoms. As many more individuals of each species
are born than can possibly survive; and as, consequently, there is a
frequently recurring struggle for existence, it follows that any being,
if it vary however slightly in any manner profitable to itself, under
the complex and sometimes varying conditions of life, will have a better
chance of surviving, and thus be NATURALLY SELECTED. From the strong
principle of inheritance, any selected variety will tend to propagate
its new and modified form.

This fundamental subject of Natural Selection will be treated at
some length in the fourth chapter; and we shall then see how Natural
Selection almost inevitably causes much Extinction of the less improved
forms of life and induces what