Eco-evolutionary dynamics and the maintenance of organismal diversity

Project Information

EcoEvoDiv

Grant agreement ID: 101088709

DOI

10.3030/101088709

EC signature date 23 March 2023

Start date 1 January 2024

End date 31 December 2028

Funded under

• European Research Council (ERC)

Total cost

€ 1 995 250,00

EU contribution

€ 1 995 250,00

Coordinated by

BIOLOGICKE CENTRUM AV CR VVI
Czechia

Periodic Reporting for period 1 - EcoEvoDiv (Eco-evolutionary dynamics and the maintenance of organismal diversity)

Reporting period: 2024-01-01 to 2026-06-30

Summary of the context and overall objectives of the project

There is growing evidence that evolution can be very rapid and intervined with ecological processes into eco-evolutionary dynamics. However, we are only beginning to understand what this mixing of ecological and evolutionary processes implies for maintenance of biodiversity in nature. Species diversity and its maintenance is traditionally studied within community ecology. Separately, maintenance of genetic and phenotypic variation within species is studied by evolutionary biology. Although interlinked, these questions are therefore usually studied separately, not considering the other level. Intriguingly, genetic variation could help maintain species diversity, and reciprocally, diversity could help maintain variation, forming a positive feedback loop. However, this hypothesis has not been empirically tested in complex ecological networks, because maintaining such networks in the laboratory is a major challenge.

In this project, we therefore experimentally test this hypothesis using a uniquely tractable network of tropical rainforest Drosophila and their parasitoids, that we developed to allow multigenerational microcosm experiments. We will manipulate species diversity and genetic variation of all species in a factorial design to test the hypothesis. We will also explore the mechanisms of interactions between diversity and variation, focusing on rapid evolution. To link the findings to natural eco-evolutionary dynamics, we will investigate mechanisms maintaining diversity and variation in the wild. Based on the empirical work we will advance eco-evolutionary concepts of organismal diversity and stability.

This project will provide a causal test of the interaction between maintenance of diversity and variation, thus linking two key questions in ecology and evolutionary biology. Uncovering the specific coexistence mechanisms will allow us to predict the importance of diversity variation feedbacks in other systems with important implications for conservation of biodiversity.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The EcoEvoDiv project investigates how species diversity in communities helps to maintain genetic and phenotypic variation in populations, and vice versa. The project utilizes Drosophila flies and their parasitic wasps from Australian rainforest as a model community system. It consists of four objectives focussing on laboratory experiments, fieldwork in natural settings, and synthesis.
In laboratory experiments we tested mechanisms by which species diversity in communities can help to maintain genetic and phenotypic variation in populations, and vice versa. We have tested how multiple selective pressures typical of more diverse communities influence adaptation. Environments with more selective pressures can restrict adaptation through trade-offs, or, on the contrary speed-up adaptation. We further tested for rapid adaptation in the system, because rapid adaptation can help maintain diversity. The analysis of these studies are ongoing, abut already brought important preliminary understanding for the main experiment of the grant. While preparing the experiments, we developed a review of experiments studying evolution in communities. We conducted a systematic literature search and identified types of experimental designs and understudied gaps in understanding. By far the most studies have targeted clonal microorganisms, and evolution in communities of sexually reproducing insects studied in our project is severely understudied.
In the fieldwork we sampled Drosophila – parasitoid networks in the Australian rainforest in frequent intervals over more than two years to understand how diversity and genetic variation interact in nature. The processing of the samples is ongoing. Many species are present year-round, making the planned population genomic analysis possible

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The analysis of the complex experiements and field sampling we conducted is underway, but we expect that the results are likely to have impact beyond the fundamental understanding of natural processes. In particular, we expect our project to inform insect pest control and conservation biology.