the principle that only those organisms best adapted to their environment will survive and reproduce

The competition between living things for survival and reproduction; Darwin considered this a key driver of evolution.

Competition between living things to survive and reproduce, where the fittest survive and others are eliminated. Darwin viewed this struggle as a key driver of evolution. Also called [[生存竞争|生存競爭|sheng1 cun2 jing4 zheng1]].

habitat; the conditions or environment in which a person or organism lives

living space; room for survival; can also refer to the historical concept of Lebensraum

the general well-being of individuals and societies, outlining negative and positive features of life; often used in a medical or sociological context

subsistence farming; subsistence agriculture