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Conservation Genetics

, Volume 1, Issue 1, pp 45–55 | Cite as

Genetic variability and gene flow in the globally, critically-endangered Taita thrush

  • Peter Galbusera
  • Luc Lens
  • Tine Schenck
  • Edward Waiyaki
  • Erik Matthysen
Article

Abstract

Analysis of 155 individuals with seven polymorphicmicrosatellite DNA markers showed significant genetic differentiationbetween the only three remaining subpopulations of the globally,critically-endangered Taita thrush. Small, recently-disturbedsubpopulations such as studied here may violate the assumptions ofmutation-drift and gene flow-drift equilibrium inherent to mostpopulation genetic tools that estimate gene flow. We thereforeidentified putative dispersers using two recently-developed assignmenttests based on individual genotypes. Previous-generation and currentmigration rates between any two subpopulations were estimated at one andzero individuals per generation, respectively. Strong congruence withnon-genetic estimates of between-fragment dispersal provided indirectevidence for the accuracy of the assignment test. From a conservationperspective, the available demographic and genetic data suggest asubstantial threat to the long-term survival of at least the smallestsubpopulation.

assignment test effective population size gene flow habitat fragmentation microsatellite DNA markers 

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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Peter Galbusera
    • 1
  • Luc Lens
    • 2
    • 3
  • Tine Schenck
    • 2
  • Edward Waiyaki
    • 3
  • Erik Matthysen
    • 2
  1. 1.Laboratory of Animal Ecology, Department of BiologyUniversity of Antwerp (UIA)WilrijkBelgium;
  2. 2.Laboratory of Animal Ecology, Department of BiologyUniversity of Antwerp (UIA)WilrijkBelgium;
  3. 3.Department of OrnithologyNational Museums of KenyaNairobiKenya

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