On The Origin of Species by Charles Darwin Chapter 3 Page 1

Struggle For Existence

Its bearing on natural selection — The term used in a wide sense — Geometrical ratio of increase — Rapid increase of naturalised animals and plants — Nature of the checks to increase — Competition universal — Effects of climate — Protection from the number of individuals — Complex relations of all animals and plants throughout nature — Struggle for life most severe between individuals and varieties of the same species: often severe between species of the same genus — The relation of organism to organism the most important of all relations.

1.

Before entering on the subject of this chapter I must make a few preliminary remarks to show how the struggle