Population size
hideIn 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.
For more information about Population size, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with population size
Abundance of a look-alike species clouds population status of a million dollar fish
13 hours ago |
not rated yet |
1
The prized white marlin, sought by anglers in million dollar prize tournaments and captured incidentally in commercial fisheries, is among the most overfished marine species under international management and the subject ...
Physicists Show that Correlated Environmental Variations Can Quicken Extinctions
Jan 13, 2009 |
3.8 / 5 (6) |
5
(PhysOrg.com) -- In general, population extinction is a natural process. For one reason or another, an estimated 99.9% of all species that have lived on Earth are now extinct. However, the reasons for a species ...
Buried Coins Key to Roman Population Mystery?
Oct 05, 2009 |
3.5 / 5 (14) |
2
(PhysOrg.com) -- The first century BC in Italy was culturally a brilliant age, unequaled by any other period in Roman history. It was a time of Cicero, Caesar, Vergil, Horace and many other major literary ...
Study finds human population expanded during late Stone Age
Jul 29, 2009 |
4.3 / 5 (3) |
5
Genetic evidence is revealing that human populations began to expand in size in Africa during the Late Stone Age approximately 40,000 years ago. A research team led by Michael F. Hammer (Arizona Research Laboratory's Division ...
French male bears in immediate need of more females
Oct 27, 2009 |
not rated yet |
0
The population of brown bears (Ursus arctos) in France is now so small that the species might become extinct in the near future. However, there is new hope in the form of new research published October 28 in the open-access, peer-r ...
Seals quickly respond to gain and loss of habitat under climate change
Jul 10, 2009 |
4 / 5 (2) |
2
Southern Elephant seals responded rapidly to climate and habitat change and established a new breeding site thousands of kilometres from existing breeding grounds, according to new research.
High population density triggers cultural explosions
Other Sciences / Social Sciences
Jun 04, 2009 |
4.8 / 5 (8) |
3
Increasing population density, rather than boosts in human brain power, appears to have catalysed the emergence of modern human behaviour, according to a new study by UCL (University College London) scientists published in ...
Study finds potential disease threats to Washington sea otters
May 06, 2009 |
not rated yet |
0
Many of Washington State's sea otters are exposed to the same pathogens responsible for causing disease in marine mammal populations in other parts of the country, according to a study published by researchers from NOAA's ...
Decline of shorebird linked to bait use of horseshoe crabs
Biology /
Feb 17, 2009 |
not rated yet |
0
Declining numbers of a shorebird called the red knot have been linked to bait use of horseshoe crabs.
Estimation of isolation times in the Drosophila simulans complex
Jun 25, 2008 |
not rated yet |
0
The Drosophila simulans species complex continues to serve as an important model system for the study of new species formation. The complex is comprised of the cosmopolitan species, D. simulans, and two island endemics, D. ...
