Plastic and genetic responses of a wild bird population to recent environmental changes

Principal researcher: David Canal

Period: 2019-2022

Understanding the mechanisms by which natural populations respond to environmental fluctuations and their consequences for population persistence are crucial under the ongoing global climate change (CC). Using long-term data from a natural population of a migrant passerine, I will investigate population-level responses to current environmental changes to discriminate whether these responses result from phenotypic plasticity of individuals, changes in between-individual variations or genetic changes affecting mean phenotypes. I will focus on various phenotypic traits characterized by different degrees of within-individual plasticity ranging from traits expressed with little within-individual variation (e.g. morphological traits) to highly flexible, behavioural traits. In addition, I aim to determine the key environmental factors that influence different types of responses acting on different traits. Given i) the availability of morphologic, life history and behavioural data as well as the imminent obtainment of genome-wide genetic markers for several generations of individuals and ii) the fact that the mechanisms mediated by within-individual and between-individual variances have been traditionally neglected in studies of population level responses to CC, the proposed research will solidly expand our understanding of the mechanisms that contribute to adaption to predictable and unpredictable changes in the environment.

Function and regulation of the tegumentary coloration in Chimango Caracaras

Principal researcher: David Canal

Period: 2020-2022

The evolution of ornamental colorations is a central issue in behavioral and evolutionary biology. To understand the function and evolution of these characters, it is necessary to understand the mechanisms that regulate their expression and how they are linked to physical state and individual quality. Carotenoid-based colorations, which are frequent in birds, constitute an ideal study model to investigate these processes. Further, this type of characters have great interest in the field of ecotoxicology because i) they are closely linked with the physiological state of the animal -making them useful in environmental monitoring processes- and ii) due to its key role in social communication, they could mediate sublethal effects of anthropic action on wildlife. The general objective of this project is to investigate the physiological mechanisms involved in the expression of the coloration of the tarsi and ceres of Chimango Caracaras Milvago chimango, as well as to elucidate whether the expression of this coloration is related to the individual quality and the degree of habitat alteration.

Eco-evolutionary dynamics of sexual traits in wild bird populations under changing environment

Principal researcher: Jesús Matínez Padilla.

Period: 2020-2023

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 .