Population Biology

Population biology is the study of populations of organisms, especially the growth and regulation of population size, population genetics, demography and life history evolution, and interactions among species. A population is a group of individuals of the same species that have a high probability of interacting with each other. A simple example would be trout in a lake, or moose on Isle Royale, although in many cases the boundaries delineating a population are not as clear cut. The term population biology is often used interchangeably with population ecology and population genetics.

Although Malthus's book, An Essay on the Principle of Population, dealt only with the economy of human population fluctuations, which he theorized as being related to finite food resources, abundance and decadence, it gave inspiration to Charles Darwin for the theoretical basis of his seminal work, The Origin of Species.

Charles Darwin in his autobiography (written 1876, edited by his son and published 1887), pp. 34–35.

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