(biology, ecology) The study of populations of organisms, especially the growth and regulation of population sizes and genetics, and the effects of interactions between species.

plural of population density

A sudden (normally temporary) decrease in a population typically due to a stressful situation

(law) A process in which the major political parties compete with each other to be tough on crime.

Synonym of penal populism

A graphical illustration of the distribution of a population (typically that of a country or region of the world) by age groups and sex; it typically forms the shape of a pyramid when the population is growing.

A population that is inferred to have existed based on data that has been reconstructed rather than on direct sampling.

plural of population pyramid