Populations

Populations are studied, in exacting, in a branch of ecology known as population biology, and in population genetics. In population dynamics, size, age and sex structure, mortality, reproductive behavior, and development 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 members of the varieties. 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 dilapidated areas of the region. Biological dispersal is one of the key elements upsetting such populations; if dispersal is sufficiently low for a prolonged period of time, speciation is likely to be a consequence.
Population growth is varying in population over time. It also can be quantified as the change in the number of individuals in a population per piece time. The term population growth can technically refer to any species, but almost always refers to humans, and it often used easily for the more specific demographic term population growth rate, and is often used to refer specifically to the expansion of the population of the world.