The evolution of mutualistic interactions and of aggregated dispersal

Mutualistic interactions have long fascinated biologists. If a mutualism benefits the recipients of the mutualistic act but come at a cost to the provider, it is an evolutionary puzzle why interactions why such interactions exist. This puzzle has been solved for the simpler version where the positive interaction is between individuals of the same species. In that case the act is often called altruism or cooperation and its evolution can explained if the provision of the benefit is somehow intrinsically linked to the receipt of benefits from others. If this is at play within a species, the theories of reciprocity and inclusive fitness theory explain why altruistic acts evolve [1,2].

Mutualisms -positive interactions that occur between different species - have been described at various levels. They appear to be common among microbial communities but are also found higher organisms. Many plants appear to engage in mutualistic acts with microbes, that they take with them on their seeds. A further famous example is the interaction between mites, yeasts and dung beetles, in which the community of organisms appears to travel from one place to the next as a group [3].

In contrast to the single species counterpart, we do not have a well-developed understanding under what circumstances such interactions can evolve and be maintained. We know that it is crucial in the interaction that the mutualistic partners need to encounter each other with some regularity [e.g. 4-6] .

In this project we will employ models and adaptive dynamics to study when and how mutualisms will evolve. These models will take the form of a haystack model: a collections of demes that are seeded by groups of individuals [e.g 7]). After a time of interaction, the demes yield a new generation of dispersers that seed the next round of interaction. Of particular interest is the question if and how clumps of dispersers of different species can favour the evolution of a mutualism and whether, if a mutualism exists, whether clumping will evolve.

To apply follow link and instructions at https://www.royalholloway.ac.uk/studying-here/applying/postgraduate/how-to-apply/. Please indicate supervisor’s last name "Jansen" and project title in your application. Application deadline 12 March 2023