Location of Repository

Modelling the impact of colonisation on genetic diversity and differentiation of forest trees: interaction of life cycle, pollen flow and seed long-distance dispersal.

By F. Austerlitz and P. H. Garnier-Géré

Abstract

International audienceIt was shown previously that the long lifespan and juvenile phase of trees strongly attenuate founder effects during colonisation in a diffusive dispersal model. However, this model yielded too slow a colonisation rate in comparison with palynological data for temperate forest trees. Since rare long-distance dispersal events have been shown to increase considerably colonisation rates in population dynamics models, we investigate here the impact of long-distance dispersal on within-population diversity (H(S)) and among-population differentiation (F(ST)) during the colonisation process. We use a stochastic approach and compare several dispersal strategies, ranging from very rare dispersal events of large amplitude to more frequent events of smaller amplitude. Using a simulation approach, which takes into account tree life-history traits, we show that long-distance dispersal events increase colonisation speed, and yield much larger founder effects in comparison with the diffusive model. The two models that include intermediate- and long-distance dispersal events show stronger deviations from experimental F(ST) values during and at the end of the colonisation process than the model with more frequent events of smaller dispersal variance. Furthermore, the introduction of a high level of pollen flow has a much more limited impact on models that include long-distance dispersal than on a diffusive dispersal model. The relatively high H(S) values that were obtained in all models are discussed according to the assumed mutation rate and effective population size. This study is an example of how observed genetic data can provide additional evidence on the best demographic model for a given species or group of species

Topics: [SDV.GEN.GPO] Life Sciences [q-bio]/Genetics/Populations and Evolution [q-bio.PE]
Publisher: Nature Publishing Group
Year: 2003
DOI identifier: 10.1038/sj.hdy.6800243
OAI identifier: oai:HAL:hal-00531062v1
Provided by: Hal-Diderot
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • https://hal.archives-ouvertes.... (external link)
  • https://hal.archives-ouvertes.... (external link)
  • https://hal.archives-ouvertes.... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.