The effects of subdivision on the genetic divergence of populations and species

Authors
Citation
J. Wakeley, The effects of subdivision on the genetic divergence of populations and species, EVOLUTION, 54(4), 2000, pp. 1092-1101
Citations number
45
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biology,"Experimental Biology
Journal title
EVOLUTION
ISSN journal
0014-3820 → ACNP
Volume
54
Issue
4
Year of publication
2000
Pages
1092 - 1101
Database
ISI
SICI code
0014-3820(200008)54:4<1092:TEOSOT>2.0.ZU;2-W
Abstract
An island model of migration is used to study the effects of subdivision wi thin populations and species on sample genealogies and on between-populatio n or between-species measures of genetic variation. The model assumes that the number of demes within each population or species is large. When popula tions (or species), connected either by gene flow or historical association , are themselves subdivided into demes, changes in the migration rate among demes alter both the structure of genealogies and the time scale of the co alescent process. The time scale of the coalescent is related to the effect ive size of the population, which depends on the migration rate among demes . When the migration rate among demes within populations is low, isolation (or speciation) events seem more recent and migration rates among populatio ns seem higher because the effective size of each population is increased. This affects the probability of reciprocal monophyly of two samples, the ch ance that a gene tree of a sample marches the species tree, and relative li kelihoods of different types of polymorphic sites. It can also have a profo und effect on the estimation of divergence times.