Joint evolution of differential seed dispersal and self‐fertilization |
| |
Authors: | R Iritani P‐O Cheptou |
| |
Affiliation: | 1. Department of Integrative Biology, University of California, Berkeley, CA, USA;2. Biosciences, College of Life and Environmental Science, University of Exeter, Exeter, UK;3. Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan;4. UMR 5175 CEFE‐Centre d'Ecologie Fonctionnelle et Evolutive (CNRS), Montpellier Cedex 05, France |
| |
Abstract: | Differential seed dispersal, in which selfed and outcrossed seeds possess different dispersal propensities, represents a potentially important individual‐level association. A variety of traits can mediate differential seed dispersal, including inflorescence and seed size variation. However, how natural selection shapes such associations is poorly known. Here, we developed theoretical models for the evolution of mating system and differential seed dispersal in metapopulations, incorporating heterogeneous pollination, dispersal cost, cost of outcrossing and environment‐dependent inbreeding depression. We considered three models. In the ‘fixed dispersal model’, only selfing rate is allowed to evolve. In the ‘fixed selfing model’, in which selfing is fixed but differential seed dispersal can evolve, we showed that natural selection favours a higher, equal or lower dispersal rate for selfed seeds to that for outcrossed seeds. However, in the ‘joint evolution model’, in which selfing and dispersal can evolve together, evolution necessarily leads to higher or equal dispersal rate for selfed seeds compared to that for outcrossed. Further comparison revealed that outcrossed seed dispersal is selected against by the evolution of mixed mating or selfing, whereas the evolution of selfed seed dispersal undergoes independent processes. We discuss the adaptive significance and constraints for mating system/dispersal association. |
| |
Keywords: | adaptive dynamics evolutionary constraints inbreeding depression mating system metapopulation pollen limitation seed dispersal self‐fertilization |
|
|