Conservation Genetics

, Volume 5, Issue 3, pp 357–365 | Cite as

Low RAPD Variation and Female-Biased Sex Ratio Indicate Genetic Drift in Small Populations of the Dioecious Conifer Taxus Baccata in Switzerland

  • Karin Hilfiker
  • Felix Gugerli
  • Jean-Philippe Schütz
  • Peter Rotach
  • Rolf Holderegger


Small populations are prone to genetic drift as a consequence of random sampling effects. We investigated whether we could detect such random sampling effects in the English yew (Taxus baccata), a dioecious conifer species occurring in scattered populations in Switzerland. Seven pairs of small and large populations were analyzed using random amplified polymorphic DNA (RAPD) marker bands from 20 individuals per population. Several genetic parameters (mean marker band frequency deviation, molecular variance, population differentiation) indicated that small populations experienced genetic drift. These genetic differences between small and large populations of yew were paralleled by an increased sex ratio bias towards a higher number of females in the small populations. Our findings support earlier assumptions that the Swiss occurrences of yew may be described as metapopulation dynamics, characterized by local colonization and extinction events leading to the observed genetic drift.

gender bias genetic variation gymnosperm population size forest tree species 


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Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • Karin Hilfiker
    • 1
    • 2
  • Felix Gugerli
    • 1
  • Jean-Philippe Schütz
    • 2
  • Peter Rotach
    • 2
  • Rolf Holderegger
    • 1
  1. 1.Division of Ecological GeneticsSwiss Federal Research Institute WSLBirmensdorfSwitzerland
  2. 2.Chair of SilvicultureSwiss Federal Institute of Technology ZürichZürichSwitzerland

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