Effects of population size and metapopulation dynamics on a mating-system polymorphism.

Détails

ID Serval
serval:BIB_43AE4A04582C
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Effects of population size and metapopulation dynamics on a mating-system polymorphism.
Périodique
Theoretical Population Biology
Auteur(s)
Pannell J.R., Barrett S.C.
ISSN
0040-5809 (Print)
ISSN-L
0040-5809
Statut éditorial
Publié
Date de publication
2001
Peer-reviewed
Oui
Volume
59
Numéro
2
Pages
145-155
Langue
anglais
Résumé
The evolutionary dynamics of neutral alleles under the Wright-Fisher model are well understood. Similarly, the effect of population turnover on neutral genetic diversity in a metapopulation has attracted recent attention in theoretical studies. Here we present the results of computer simulations of a simple model that considers the effects of finite population size and metapopulation dynamics on a mating-system polymorphism involving selfing and outcrossing morphs. The details of the model are based on empirical data from dimorphic populations of the annual plant Eichhornia paniculata, but the results are also of relevance to species with density-dependent selfing rates in general. In our model, the prior selfing rate is determined by two alleles segregating at a single diploid locus. After prior selfing occurs, some remaining ovules are selfed through competing self-fertilisation in finite populations as a result of random mating among gametes. Fitness differences between the mating-system morphs were determined by inbreeding depression and pollen discounting in a context-dependent manner. Simulation results showed evidence of frequency dependence in the action of pollen discounting and inbreeding depression in finite populations. In particular, as a result of selfing in outcrossers through random mating among gametes, selfers experienced a "fixation bias" through drift, even when the mating-system locus was selectively neutral. In a metapopulation, high colony turnover generally favoured the fixation of the outcrossing morph, because inbreeding depression reduced opportunities for colony establishment by selfers through seed dispersal. Our results thus demonstrate that population size and metapopulation processes can lead to evolutionary dynamics involving pollen and seed dispersal that are not predicted for large populations with stable demography.
Mots-clé
Alleles, Angiosperms/genetics, Angiosperms/physiology, Genetic Variation, Models, Genetic, Pollen/genetics, Pollen/physiology, Polymorphism, Genetic, Population Density, Population Dynamics
Pubmed
Web of science
Création de la notice
22/09/2011 15:06
Dernière modification de la notice
20/08/2019 13:47
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