Adaptation of Fragmented Freshwater species Assemblages In Rapidly-changing environmentS
Informations
- Funding country
France- Acronym
- -
- Start date
- 10/1/2012
- End date
- 3/31/2016
- Budget
- 399,174 EUR
Fundings
| Name | Role | Start | End | Amount |
|---|---|---|---|---|
| BIOADAPT - Adaptation - des gènes aux populations. Génétique et biologie de l'adaptation aux stress et aux perturbations - 2011 | Grant | 10/1/2012 | 3/31/2016 | 399,174 EUR |
Organisations
Abstract
We will study how fragmented systems (metapopulations and metacommunities) adapt to climate change and bioinvasions. The specificity of these systems is that diversity is regulated at the landscape scale by perturbations that result in local turnovers of genotypes and species. The fitness of a genotype emerges from its ability to colonize new patches, to compete with others within patches, and to avoid extinction during perturbation. Equilibria due to tradeoffs among these abilities are compromised by global change, which modifies both the rate of perturbation and the competitive environment (through the arrival of invasive species). Given the increasing importance of fragmented habitats, understanding how communities and species evolve in response to such changes is a major goal. /nWe focus on small tropical freshwater habitats, (ponds and streams) in the Antilles. They are naturally fragmented and are exposed to dramatic climate change, resulting in increased frequency of desiccation events (perturbation). At the same time many invasive species have spread in these habitats. Our first major objective is to decompose adaptation in these systems by quantifying colonisation ability, resistance to perturbation and competitiveness in a set of species in a community, and/or a set of genotypes in a species. Thus we will explain past changes, and predict future changes, in the frequency of these species/genotypes, i.e. the adaptive trajectory of the community/species in response to increased perturbation rates and bioinvasions. To this end we will rely on exceptional datasets: yearly surveys performed for >14yr in Guadeloupe ponds / Martinique rivers. The Guadeloupe ponds harbour communities of freshwater molluscs (similar in their life habits) while Martinique rivers mainly contains one species (Melanoides tuberculata) which is parthenogenetic and is composed of a set of morphologically identifiable clones. These clones compete with each other, providing a large-scale evolutionary experiment at the scale of the island. Using state-of-the-art bayesian patch-occupancy models, as well as more innovative analysis based on graph-theory, we will model the temporal trajectories of these systems. These results will potentially have a large impact because no such analysis has ever been done on a n-species or n-genotype system, highlighting a big gap between theory and field studies. In parallel, we will concentrate our efforts on laboratory measures of life-history and drought-resistance traits to uncover the phenotypic and genetic architecture of colonization, resistance and competition abilities. /nWe will also adress how trait evolution might affect coexistence by looking at rapid evolution of traits in a pair of related species (Physa acuta and P. marmorata), one of which is a recent invader, and the other a local species. Theoretical models will be made to understand which pairs (or communities) of species or genotypes are not only ecologically, but also evolutionarily stable, and how character displacement may (or not) take place in the competition-colonisation-resistance phenotype space. This theory will be applied to a two-species subset (one invasive, one indigenous) of our data in Guadeloupe. We will perform a phenotypic scan by looking for rapid local adaptation to new perturbation regimes in the invasive species; and rapid character displacement in the local species when the invader arrives. /nThis project brings together a pluridisciplinary consortium (ecology, quantitative and molecular genetics, mathematical modeling), with a good equilibrium between Empiricists and theorists, field ecology and lab experiments, evolutionary genetics and community ecology. The competences of the different members are highly complementary, and most of them have collaborated and written joint papers in the past. /n