Chaine A.S.,French National Center for Scientific Research |
Legendre S.,Laboratoire Ecologie and Evolution |
Clobert J.,French National Center for Scientific Research
PeerJ | Year: 2013
Dispersal plays a key role in natural systems by shaping spatial population and evolutionary dynamics. Dispersal has been largely treated as a population process with little attention to individual decisions and the influence of information use on the fitness benefits of dispersal despite clear empirical evidence that dispersal behavior varies among individuals. While information on local density is common, more controversial is the notion that indirect information use can easily evolve.We used an individual-based model to ask under what conditions indirect information use in dispersal will evolve. We modeled indirect information provided by immigrant arrival into a population which should be linked to overall metapopulation density. We also modeled direct information use of density which directly impacts fitness. We show that immigrant-dependent dispersal evolves and does so even when density dependent information is available. Use of two sources of information also provides benefits at the metapopulation level by reducing extinction risk and prolonging the persistence of populations. Our results suggest that use of indirect information in dispersal can evolve under conservative conditions and thus could be widespread. © 2013 Chaine et al.
Bleu J.,Laboratoire Ecologie and Evolution |
Bleu J.,Mohammed V University |
Bleu J.,Agro ParisTech |
Bleu J.,French National Center for Scientific Research |
And 9 more authors.
Animal Behaviour | Year: 2012
Choice for mate quality and number of mates are key components of female mating strategies. We investigated how selection on female choosiness also influences number of matings in various ecological conditions. In our individual-based model, females choose their first mate according to an evolving acceptance threshold and then mate with males of increasing quality (trade-up choice). We simulated evolution of this threshold under various conditions of density, sex ratio and mating cost. Thresholds rapidly evolve towards a small set of values that depend on the tested parameters. Consistent with intuitive predictions, choosier females are selected when either number of encounters with males or mating cost is high. Selection results in most females sharing the same threshold. Variation in female mating patterns remains because some variation in thresholds is maintained, at least by mutations, and because of random events affecting number of matings. Our model indicates that mating cost strongly affects evolution of female choosiness and mating frequency. Moreover, it influences the relative importance of other factors: when mating cost is low, selection on acceptance thresholds is weak and relatively more females use thresholds that differ from the norm. In that context, mate quality is therefore the most important factor affecting female reproductive success. When mating cost is high, females evolve thresholds such that both the cost of multiple mating and the risk of remaining unmated become as important as mate quality. High mating cost, by selecting for high choosiness, also leads to females mating with fewer males. © 2011 The Association for the Study of Animal Behaviour.