+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Effect of unsampled populations on the estimation of population sizes and migration rates between sampled populations



Effect of unsampled populations on the estimation of population sizes and migration rates between sampled populations



Molecular Ecology 13(4): 827-836



Current estimators of gene flow come in two methods; those that estimate parameters assuming that the populations investigated are a small random sample of a large number of populations and those that assume that all populations were sampled. Maximum likelihood or Bayesian approaches that estimate the migration rates and population sizes directly using coalescent theory can easily accommodate datasets that contain a population that has no data, a so-called 'ghost' population. This manipulation allows us to explore the effects of missing populations on the estimation of population sizes and migration rates between two specific populations. The biases of the inferred population parameters depend on the magnitude of the migration rate from the unknown populations. The effects on the population sizes are larger than the effects on the migration rates. The more immigrants from the unknown populations that are arriving in the sample populations the larger the estimated population sizes. Taking into account a ghost population improves or at least does not harm the estimation of population sizes. Estimates of the scaled migration rate M (migration rate per generation divided by the mutation rate per generation) are fairly robust as long as migration rates from the unknown populations are not huge. The inclusion of a ghost population does not improve the estimation of the migration rate M; when the migration rates are estimated as the number of immigrants Nm then a ghost population improves the estimates because of its effect on population size estimation. It seems that for 'real world' analyses one should carefully choose which populations to sample, but there is no need to sample every population in the neighbourhood of a population of interest.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 012005965

Download citation: RISBibTeXText

PMID: 15012758

DOI: 10.1111/j.1365-294x.2004.02101.x


Related references

Seeing ghosts: the effect of unsampled populations on migration rates estimated for sampled populations. Molecular Ecology 14(1): 67-73, 2005

Estimation of migration rates and population sizes in geographically structured populations. NATO Science Series General Sub-Series A Life Sciences, 306: 39-53, 1998

Effective population sizes and migration rates in fragmented populations of an endangered insect (Coenagrion mercuriale: Odonata). Journal of Animal Ecology 76(4): 790-800, 2007

Using temporally spaced sequences to simultaneously estimate migration rates, mutation rate and population sizes in measurably evolving populations. Genetics 168(4): 2407-2420, 2004

Maximum-likelihood estimation of migration rates and effective population numbers in two populations using a coalescent approach. Genetics 152(2): 763-773, 1999

Allelic rates and population sizes of two populations of D melanogaster from cellar and vineyard. Drosophila Information Service, 85-86 No. 61, 1985

Effect of population patchiness and migration rates on the adaptation and divergence of vesicular stomatitis virus quasispecies populations. Journal of General Virology 80: 2051-2059, 1999

Estimation of rates of recombination and migration in populations of plant pathogens. Phytopathology 90(4): 320-323, 2008

Mutation rates, population sizes and amounts of electrophoretic variation of enzyme loci in natural populations. Genetics 92(2): 623-646, 1979

Determination of sample sizes for the estimation of Onchocerca volvulus infection rates in biting populations of Simulium ochraceum sl and its application to ivermectin control programs. Journal of Medical Entomology 35(5): 745-757, Sept, 1998

Estimation of effective size and migration rates in twelve European pig populations using non equilibrium model. Proceedings of the 8th World Congress on Genetics Applied to Livestock Production, Belo Horizonte, Minas Gerais, Brazil, 13-18 August, 2006: 33-19, 2006

Temporal sampling helps unravel the genetic structure of naturally occurring populations of a phytoparasitic nematode. 1. Insights from the estimation of effective population sizes. Evolutionary Applications 9(3): 489-501, 2016

Density dependent rates of population growth estimation in laboratory populations. American Naturalist 128(2): 282-293, 1986

Determination of sample sizes for the estimation of Onchocerca volvulus (Filarioidea: Onchocercidae) infection rates in biting populations of Simulium ochraceum s.l. (Diptera: Simuliidae) and its application to ivermectin control programs. Journal of Medical Entomology 35(5): 745-757, 1998