Grant: Discovery Grants Program - Individual

In many species there is variation within sexes in the tactics used to obtain mates. The most common form of these alternative reproductive tactics (ARTs) occurs when large males compete directly with each other for mates, while smaller males use a tactic that allows them to avoid competition with large males. North American sunfishes are a model system for studying ARTs. Most males use a parental tactic in which they build nests where females release eggs, after which the parental male cares for the eggs. Smaller males use a sneaker tactic in which they dart into a nest at the moment of spawning or a satellite tactic that mimics female characteristics to deceive parental males into accepting the satellite in his nest. My research program will work to understand how the presence of ARTs has shaped the evolution and ecology of sunfishes. My first objective is to understand how female sunfish select mates, and determine if the presence of ARTs makes it easier or harder for females to select a preferred mate. My second objective is to understand how satellite males mimic female characteristics to escape recognition by parental males, and understand how parental males and juvenile bluegill recognize individuals that are related to themselves within a nest (kin). My third objective is to understand if foraging differences influence the immune system through the bacteria and parasites that individuals encounter in their diets, and if ARTs act as an obstacle to foraging and immune specializations. My overarching goals are to understand how selection affects fitness in wild populations and to discover the basis of adaptations. This novel research program includes a number of innovative elements designed to address fundamental questions about animal behaviours. Past studies of ARTs have overwhelmingly focused on male tactics, while largely ignoring the role of females. My research will be among the first to provide a detailed examination of female mating preferences, why those preferences exist, and whether male ARTs override female preferences or provide additional opportunities for female choice. Female mimicry is a key element of the success of the satellite mating tactic, but how this mimicry is achieved and the degree to which parental males can recognize these imposters has never previously been addressed. Kin recognition is widespread in many animals, but the mechanisms underlying it are poorly understood outside of a few model systems. My research will help to understand this behaviour in a fish in which kin recognition is fundamental to the ability of parental males to allocate parental care adaptively in response to the number of their own offspring in their nest. Finally, my research will explore the role of foraging and immune specialization in the formation of new species.