Abstracts (first author)
Eco-evolutionary dynamics and the evolution of sex
The evolution of sexual reproduction is one of the most important and controversial problems in evolutionary biology because sexual reproduction is almost universal while its inherent costs have made its maintenance difficult to explain. Major hypotheses on the evolution of sex predict sex to be advantageous when the environment changes frequently over time. Recurrent change can occur as a result of eco-evolutionary feedback dynamics but has not been considered in the context of the evolution of sex. An eco-evolutionary feedback loop occurs when environmental change causes natural selection in a population within a few generations, and the resulting trait evolution then modifies the environment, causing further selection and evolution, and so on. An example for this eco-evolutionary feedback comes from a predator-prey system where the algal prey evolves a defence against predation when grazing by rotifer is intense, and loses the defence, but gains competitive ability when the predators (rotifers) are scarce and prey are abundant. I present experimental results showing that the rate of sex evolved to higher rates in the rotifer when eco-evolutionary feedback dynamics occur. In contrast, the rate of sex evolved to lower rates in control populations where the trait evolution in the algae and thus the eco-evolutionary feedback was prohibited. Thus the changes driven by the interplay of ecological and evolutionary change on one time scale can provide conditions allowing for a more globally relevant explanation for the evolution of sex.