Grants and Contributions:

Grant or Award spanning more than one fiscal year. (2017-2018 to 2022-2023)

Mating systems are often described as a characteristic of a species based on one or a few populations. However, considerable intraspecific differences in mating system structure can be driven by variation in ecological conditions within and among populations. In animals, mating system structure results from the interplay among mechanisms of sexual selection, including competition and mate choice, as well as conflict between the sexes over mating opportunities and rates. For example, the distribution of available mates across space and time influences the degree to which they can be monopolized. Inter- and intra-population differences in mate distribution can have a significant effect on the success of different mechanisms used to obtain them, which can lead to intraspecific variation in sexually-selected traits. This research seeks to understand how differences in ecological conditions can result in changes in the distribution of reproductive success, the relative influence of different mechanisms of sexual selection at both the individual and gamete levels, and the evolution of sexually-selected traits. To this end, this work will combine field research in salmonid fishes in Eastern Canada with laboratory experiments using small freshwater fish from the genus Oryzias . During the course of this research programme, four graduate students and six undergraduate students will receive training in field or experimental techniques related to fish behaviour and collection, molecular analysis of parentage, and statistical analysis of biological data. Graduate students and Honours students will also receive training in the preparation of manuscripts for publication. As a whole, this research will contribute to our understanding of the evolution of mating systems and sexually-selected traits, and will provide a new perspective on the consequence of variation in selection within and among populations.