Populations

Populations are studied, in particular, in a branch of ecology known as population biology, and in population inheritance. In population dynamics, size, age and sex structure, mortality, reproductive behaviour, and growth of a population are studied. In biology, an isolated population denotes a breeding group whose members breed mostly or solely among themselves, usually as a result of physical isolation, although biologically they could breed with any member of the species. If there are several completely or nearly completely secluded populations in the global population of a taxon, these are called subpopulations. The metapopulation is a network of subpopulations in a given area ,where the individuals of the various subpopulations are able to cross ramshackle areas of the region. Biological dispersal is one of the key elements disturbing such populations; if dispersal is sufficiently low for a prolonged period of time, speciation is likely to be a significance.

Demography is the learning of human populations. Its three central foci are the processes of fertility, mortality, and migration, though the field encompasses many extent of population change including the family , public health, work and the labor force, and family planning. Various aspects of human activities in populations are also studied in sociology, economics, and geography. Study of populations is almost always governed by the laws of probability, and the conclusions of the studies may thus not always be relevant to some individuals. This odd factor may be reduced by statistical means, but such a generalization may be too vague to imply anything. Demography is used extensively in marketing, which relates to economic units, such as retailers, to potential customers.