Subventions et des contributions :

Subvention ou bourse octroyée s'appliquant à plus d'un exercice financier. (2017-2018 à 2022-2023)

This proposal seeks to develop and analyze mathematical models to understand how adaptive processes and population heterogeneity combine to affect coevolution, species interactions, and the response of population sizes to environmental change. It thereby extends the work I have carried out under my current NSERC Discovery Grant ‘Applications of consumer-resource models in ecology and evolution’ (RGPIN 227077-10).
Much of population and community ecology has been based on theory that assumes that species consist of identical individuals (or units of biomass) with characteristics that do not change over time. While there are now many articles that explore particular exceptions to these generalizations, most have concentrated on the simplest multi-species examples (2-3 species) and have only relaxed one of these two restrictive assumptions. Research has already shown that population heterogeneity and individual adaptation each have the potential to dramatically change predictions about how species’ abundances and traits change in response to a change in the abundance of other species or a change in the environment that affects the properties of the species.
The proposed research will analyze mathematical models of simple food webs involving between 2 and 6 species. It will focus on how an environmentally-caused change in the ecological characteristics of one or more species affects the future abundances of all of the species in the food web. The characteristics include food uptake rates, maximal birth rates and death rates, as well as others. The models will differ from those used in most previous work by the inclusion of both behavioural and evolutionary traits influencing the same ecological parameter; for example a predator's time spent foraging as well as its maximal capture rate of prey. The research will explore the conditions under which environmental change increases a species' immediate rate of population growth while decreasing its ultimate population size. Recent work (Cortez and Abrams, 2016) has shown that such traits are likely to occur in a wide variety of simple food webs. The research proposed here will examine whether the inclusion of more interacting species and adaptively changing characteristics within species makes such unexpected responses more or less likely to occur. It should also help to understand how evolutionary change within food webs is likely to change the initial population shifts that occur following environmental change. This will help to design both harvesting strategies for exploited species and recovery plans for endangered species.