Disentangling interacting key processes of eco-evolutionary community dynamics

• Applicant: Dr. Lynn Govaert
• Subject Area: Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions ; Evolution, Anthropology
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 511084840

Protecting Earth’s biodiversity and predicting species responses to global change are main challenges that humans face. When environments change, individuals can migrate to track their environmental optimum, or can change traits to cope with the new environmental conditions. In the past decades, studies have increasingly shown that trait evolution to environmental change can be surprisingly fast. As ecology and evolution can occur on similar time scales, they can dynamically interact, resulting in eco-evolutionary dynamics and feedbacks. Given that environmental change alters both ecological and evolutionary processes, one needs to take an eco-evolutionary perspective to make reliable predictions of species responses to global change. In nature, all species are embedded within communities, in which multiple species interact and simultaneously evolve to environmental change. Yet, many studies on eco-evolutionary dynamics focus on evolutionary responses of a single species. Hence, we currently lack a general understanding of species responses to environmental change in a multi-species setting. In this proposal, I suggest that explicitly accounting for interactions between key evolutionary processes (selection, genetic drift, gene flow, mutation) and community processes (species sorting, ecological drift, dispersal, speciation) will yield a more mechanistic understanding of species and community responses to environmental change, and will result in a more predictive framework. In the proposed project, I will combine experimental and theoretical approaches with field-based observations to address three questions: (i) When to expect strong interactions between evolutionary and community processes – with a focus on the interaction between selection and species sorting? (ii) How does drift alter the interaction between selection and species sorting? (iii) How does migration alter the interaction between selection and species sorting? Given the complexity of the questions and the experiments, I will use freshwater ciliates, which have a longstanding history of being used to experimentally test conceptual questions in population and community ecology as well as evolutionary biology. I will combine the experimental results with theoretical dynamic models, and translate the findings to field observations. To date, no study has explicitly designed experiments or dynamic models including interactions between key evolutionary and community processes in a comprehensive way. While predicting species responses to global change is challenging, it is pressing that we address the complexity of the community when assessing such species responses to environmental change. The research described in this proposal will provide a crucially needed step in this direction.

• DFG Programme: Independent Junior Research Groups