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In population genetics and population ecology, population size (usually denoted N) is the number of individual organisms in a population.

The effective population size (Ne) is defined as "the number of breeding individuals in an idealized population that would show the same amount of dispersion of allele frequencies under random genetic drift or the same amount of inbreeding as the population under consideration." Ne is usually less than N (the absolute population size) and this has important applications in conservation genetics.

Small population size results in increased genetic drift. Population bottlenecks are when population size reduces for a short period of time.

Overpopulation may indicate any case in which the population of any species of animal may exceed the carrying capacity of its ecological niche.

See also[edit]

Original courtesy of Wikipedia: http://en.wikipedia.org/wiki/Population_size — Please support Wikipedia.
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The Globalist
Sat, 14 Nov 2015 22:56:03 -0800

Dawn of the 22nd Century: Estimating Africa's Population Size. Projecting population size over the long term is tricky business. By The Globalist, November 15, 2015. Credit: Veronika M Shutterstock.com ...
Mon, 09 Nov 2015 12:21:23 -0800

I refer to the commentary “Change of ways led to All Blacks' triumph” (Nov 4). If Singapore sport, especially team sport, is paying attention, there is a lesson to be learnt here. New Zealand, with a population of just over 4.5 million people, swept to ...


Sun, 01 Nov 2015 05:01:04 -0800

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Tue, 03 Nov 2015 11:39:41 -0800

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