Does habitat unpredictability promote the evolution of a colonizer syndrome in amphibian metapopulations ?
Résumé
Dispersal is a central component of life history evolution. An increasing number of studies suggest that spatiotemporally variable environments may promote the evolution of “dispersal syndromes,” consisting of covariation patterns between dispersal and morphologi- cal, physiological, behavioral, and life history traits. At the interspecific scale, the “colonizer syndrome” appears to be one of the most frequently recorded associations between dispersal and life history traits, linking a high dispersal rate, high fecundity, and a short lifespan as sys- tematically combined adaptations in spatiotemporally varying environments. However, few studies have highlighted the existence of a “colonizer syndrome” at the intraspecific scale, and none have investigated how different degrees of habitat stochasticity might shape covariation patterns between dispersal and life history traits. In this study, we examined this issue in free- ranging metapopulations of the yellow-bellied toad (Bombina variegata) using capture–recap- ture data. Combining the results of this study with another recent study, we found that a high dispersal rate, high fecundity, and a short lifespan are associated in metapopulations experi- encing unpredictable environments. In contrast, a very low dispersal rate (close to zero), low fecundity and a long lifespan are associated in metapopulations occupying predictable environ- ments. We discuss these results as well as their demographic and evolutionary consequences.