TY - JOUR

T1 - Effective population size/adult population size ratios in wildlife

T2 - A review

AU - Frankham, Richard

PY - 2007

Y1 - 2007

N2 - The effective population size is required to predict the rate of inbreeding and loss of genetic variation in wildlife. Since only census population size is normally available, it is critical to know the ratio of effective to actual population size (Ne/N). Published estimates of Ne/N (192 from 102 species) were analysed to identify major variables affecting the ratio, and to obtain a comprehensive estimate of the ratio with all relevant variables included. The five most important variables explaining variation among estimates, in order of importance, were fluctuation in population size, variance in family size, form of N used (adults v. breeders v. total size), taxonomic group and unequal sex-ratio. There were no significant effects on the ration of high v. low fecundity, demographic v. genetic methods of estimation, or of overlapping v. non-overlapping generations when the same variables were included in estimates. Comprehensive estimates of Ne/N (that included the effects of fluctuation in population size, variance in family size and unequal sex-ratio) averaged only 0-10-0-11. Wildlife populations have much smaller effective population sizes than previously recognized.

AB - The effective population size is required to predict the rate of inbreeding and loss of genetic variation in wildlife. Since only census population size is normally available, it is critical to know the ratio of effective to actual population size (Ne/N). Published estimates of Ne/N (192 from 102 species) were analysed to identify major variables affecting the ratio, and to obtain a comprehensive estimate of the ratio with all relevant variables included. The five most important variables explaining variation among estimates, in order of importance, were fluctuation in population size, variance in family size, form of N used (adults v. breeders v. total size), taxonomic group and unequal sex-ratio. There were no significant effects on the ration of high v. low fecundity, demographic v. genetic methods of estimation, or of overlapping v. non-overlapping generations when the same variables were included in estimates. Comprehensive estimates of Ne/N (that included the effects of fluctuation in population size, variance in family size and unequal sex-ratio) averaged only 0-10-0-11. Wildlife populations have much smaller effective population sizes than previously recognized.

UR - http://www.scopus.com/inward/record.url?scp=55749091997&partnerID=8YFLogxK

U2 - 10.1017/S0016672308009695

DO - 10.1017/S0016672308009695

M3 - Review article

C2 - 18976539

AN - SCOPUS:55749091997

VL - 89

SP - 491

EP - 503

JO - Genetical Research

JF - Genetical Research

SN - 0016-6723

IS - 5-6

ER -