ECO-EVOLUTIONARY DYNAMICS OF SECONDARY SEXUAL TRAITS IN WILD BIRD POPULATIONS UNDER CHANGING ENVIRONMENTAL CONDITIONS
The notion that ecology and evolution are intertwined in a short-term has been notorious only in the last few decades, providing a new synthetic and yet in development framework. The concept of eco-evolutionary dynamics aims to understand the interplay between ecology and evolution, either from contemporary evolution to ecological changes (evo-to-eco) or from recent ecological changes to evolutionary change (eco-to-evo). However, the synthetic overview of eco-evolutionary dynamics of phenotypes still has deep caveats. First, unravelling the complex interactions among different sources of evolutionary change that leads adaptive divergence, beyond those driven by natural selection; second, identifying the target phenotypes where selection can act upon and where evolutionary dynamics can be observed and quantified; and third, defining the relative influence of multiple biotic- and non-biotic factors that drives the evolutionary dynamcis. However, adaptive divergence might not be the only evolutionary mechanism that promote population differentiation leading to local adaptation. A key factor that has been identified as key on driving adaptive divergence in populations is gene flow. Gene flow has been suggested as a major source at driving adaptive divergence, but its homogenising or disruptive effect on phenotypes is still controversial. We frame our project on the idea that the role of geneflow on local adaptation is mediated by environmental conditions. We make use of secondary sexual trait in as a target phenotype, since its expression is environment-dependent heritable, selected and evolutionary labile. We place our project in a natural setting where environmental conditions are changing, have a constant but variable flow of immigrant breeders of known and unknown local population and a long-term monitored population for the last 35 years population of a wild bird, the pied flycatcher. By applying a rigorous genetic protocol, we will trace eco-to-evo dynamics of secondary sexual traits using state-of-the-art quantitative genetic techniques making use of genetic pedigrees of 14 generations depth embracing more than 14,000 records. We will tease apart the relative role of different evolutionary mechanisms that promotes local adaptation arising after the action of multiple agents of selection. We will combine observational studies with field based long-term experiments, in which will particularly test the evolutionary trajectories of secondary sexual traits. The expected results will have major implications on how we understand
ecological and evolutionary processes of adaptation, with fundamental implications for the origin and maintenance of biodiversity at short temporal scales. In this proposal, we aim obtaining a better comprehension about how animal populations on short-term temporal scales respond to environmental stochasticity, which is of urging importance in the light of recent climate change.