r in mind, that though food may be
now superabundant, it is not so at all seasons of each recurring year.

I should premise that I use the term Struggle for Existence in a large and
metaphorical sense, including dependence of one being on another, and
including (which is more important) not only the life of the individual,
but success in leaving progeny. Two canine animals in a time of dearth, may
be truly said to struggle with each other which shall get food and live.
But a plant on the edge of a desert is said to struggle {63} for life
against the drought, though more properly it should be said to be dependent
on the moisture. A plant which annually produces a thousand seeds, of which
on an average only one comes to maturity, may be more truly said to
struggle with the plants of the same and other kinds which already clothe
the ground. The missletoe is dependent on the apple and a few other trees,
but can only in a far-fetched sense be said to struggle with these trees,
for if too many of these parasites grow on the same tree, it will languish
and die. But several seedling missletoes, growing close together on the
same branch, may more truly be said to struggle with each other. As the
missletoe is disseminated by birds, its existence depends on birds; and it
may metaphorically be said to struggle with other fruit-bearing plants, in
order to tempt birds to devour and thus disseminate its seeds rather than
those of other plants. In these several senses, which pass into each other,
I use for convenience' sake the general term of struggle for existence.

A struggle for existence inevitably follows from the high rate at which all
organic beings tend to increase. Every being, which during its natural
lifetime produces several eggs or seeds, must suffer destruction during
some period of its life, and during some season or occasional year,
otherwise, on the principle of geometrical increase, its numbers would
quickly become so inordinately great that no country could support the
product. Hence, as more individuals are produced than can possibly survive,
there must in every case be a struggle for existence, either one individual
with another of the same species, or with the individuals of distinct
species, or with the physical conditions of life. It is the doctrine of
Malthus applied with manifold force to the whole animal and vegetable
kingdoms; for in this case there {64} can be no artificial increase of
food, and no prudenti