Selection for traits favouring pollen dispersal and access to sexual partners
(Post-doc – 2015-2019, University of Lausanne)
A key prediction of the theory of sexual selection is that male reproductive success should be limited by the ability to access sexual partners while female reproduction should rather be limited by the ability to harvest resources. Such prediction was repeatedly formulated for anisogamous species, such as flowering plants, in which males invest much more resources than females in each gamete produced. Thanks to paternity analyses, I tested this prediction of the theory of sexual selection in the wind-pollinated species Mercurialis annua. In this species, male reproductive success, and not female one, was limited by ability to access a higher number of mates. The ability to access sexual partners was associated with longer pollen dispersal but not to larger pollen production. Furthermore, several morphological traits were correlated with longer pollen dispersal and could therefore be sexually-selected.
Evolution of life history traits in fire-prone environments
(PhD – 2010-2013, Institut des Sciences de l’Evolution de Montpellier)
During my PhD, I focused on resource allocation between growth and survival, production and dispersal of progeny and maintenance of those progeny through strategies resembling maternal care in plants. With a special focus on the evolution of plant regenerative strategies in fire prone environments, I studied the joint evolution of both climatic and fire regime niches and plant strategies. Modeling optimal resource allocation allowed me to predict that both resource availability and fire regimes affected the plant resource allocation to a seed bank maintained actively in the plant canopy. I further reconstructed the phylogeny of the genus Leucadendron which includes a broad diversity of life history traits (e.g. fire regenerative strategies, seed dispersal, pollen dispersal) in order to test the prediction of my models. Comparative analyses along the Leucadendron phylogeny highlighted that life history traits evolved jointly in the history of the genus. Further analyses modeling the evolution of climatic and fire regime niches along the Leucadendron phylogeny showed that ecological niches did not evolved independently from plant regenerative strategies.