Eco-evolutionary dynamics

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Evolution was classically considered to be a very slow force for change. Recent research, however, has revealed that evolution can proceed very rapidly in cases of dramatic environmental change. This rapid (or “contemporary”) evolution should have important consequences for ecological patterns and processes, including population dynamics (e.g., abundances of organisms), community structure (e.g., biodiversity), and ecosystem function (including ecosystem services, such as clean water, natural resources, and agricultural production). These “eco-evolutionary dynamics” have been demonstrated in many studies but nearly all of those studies were conducted in unrealistic laboratory settings. My research seeks to fill this critical information gap by understanding how eco-evolutionary dynamics play out in the real world. This research involves several model systems, including two described here that are particularly well suited for replicated experimental manipulations in nature. In Galpagos, my research focuses on how plants shape the evolution of finch beaks, and how that evolution feeds back to influence plant communities. Two key questions will be addressed. (1) How do evolving finch beak traits (size and shape) influence seed and plant communities? (2) How are specific plant species evolving in response to finch predation? These questions will be addressed through experimental manipulations (exclosures, seed removals, predation experiments) that influence the specific seed types consumed by finches. In North America, the equivalent questions are also two-fold. (1) How do differences in the foraging traits of stickleback fishes influence plankton communities in lakes and, perhaps thereby, whole lake ecosystems? (2) How do specific plankton species evolve in response to foraging by different stickleback types, again with potential consequences for communities and lake ecosystems. These questions will be addressed by introducing stickleback of different types into different lakes from which management agencies have removed all fishes (as a side effect of their efforts to remove invasive fishes). The proposed research will train at least six new PhD students, and more than 30 undergraduate students, in field methods (e.g., collection, observation, experiments), fish rearing (e.g., animal care and behaviour), experimental design (e.g., replication, controls, power), sample processing (e.g., morphometrics, spectroradiometry, stable isotopes), advanced statistics, and publication. Overall, the work will provide key information on the extent to which conservation and management practices should consider evolutionary processes. Perhaps, to a first approximation, evolution can be safely ignored; or, perhaps, evolution should be considered as an integral part of every such endeavor; or, perhaps, evolution is critically important in some cases but not others.