Display Settings:

Format

Send to:

Choose Destination
Genetics. 2005 Aug;170(4):1809-20. Epub 2005 Jun 3.

Genetic diversity and genetic differentiation in Daphnia metapopulations with subpopulations of known age.

Author information

  • 1Unité d'Ecologie et d'Evolution, Département de Biologie, Université de Fribourg, CH-1700 Fribourg, Switzerland. christoph.haag@ed.ac.uk

Abstract

If colonization of empty habitat patches causes genetic bottlenecks, freshly founded, young populations should be genetically less diverse than older ones that may have experienced successive rounds of immigration. This can be studied in metapopulations with subpopulations of known age. We studied allozyme variation in metapopulations of two species of water fleas (Daphnia) in the skerry archipelago of southern Finland. These populations have been monitored since 1982. Screening 49 populations of D. longispina and 77 populations of D. magna, separated by distances of 1.5-2180 m, we found that local genetic diversity increased with population age whereas pairwise differentiation among pools decreased with population age. These patterns persisted even after controlling for several potentially confounding ecological variables, indicating that extinction and recolonization dynamics decrease local genetic diversity and increase genetic differentiation in these metapopulations by causing genetic bottlenecks during colonization. We suggest that the effect of these bottlenecks may be twofold, namely decreasing genetic diversity by random sampling and leading to population-wide inbreeding. Subsequent immigration then may not only introduce new genetic material, but also lead to the production of noninbred hybrids, selection for which may cause immigrant alleles to increase in frequency, thus leading to increased genetic diversity in older populations.

PMID:
15937138
[PubMed - indexed for MEDLINE]
PMCID:
PMC1449778
Free PMC Article

Images from this publication.See all images (5)Free text

F igure  1.—
F igure  2.—
F igure  3.—
F igure  4.—
F igure  5.—
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk