People

My PhD work aims to characterize the genetic basis of adaptation in the three-spine stickleback (Gasterosteus aculeatus) to predation and other sources of divergent natural selection. The purpose of this work is to further understand the general mechanisms that underlie genetic variation, adaptation to novel or changing environments and speciation.

To investigate the genetic basis of morphological adaptation to predation, I will be conducting a large scale pond experiment using benthic and limnetic F2 hybrids, in the presence or absence of cutthroat trout (Oncorhynchus clarkii). There are multiple morphological traits that differ between benthic and limnetic stickleback that we believe play a role in defense against predation. During the course of my experiment (one to two years), I will be monitoring the change in frequency of the divergent alleles that underlie these morphological traits (e.g. pelvic spines and pigmentation).

I am also interested in behavioural adaptations to predation, so I am planning to use behavioural assays to characterize differences in the behavioural responses of these benthic and limnetic stickleback to cutthroat trout predation. One behaviour I am particularly interested in is the tendency of a fish (or population of fish) to school.

I am also keen to investigate how species interactions affect adaptation and speciation. In particular I would like to know how species interactions at the microbial level may influence adaptation to novel environments. To investigate this I plan to use next-generation sequencing technology, in order to determine how microbial communities associated with stickleback (in their gut) differ between populations inhabiting divergent environments.

Lastly, I am interested in the sensory basis of sexual selection. Colouration influences mate choice in many species and often has been shown to be a reliable proxy for male quality. However, the molecular basis of female preferences for colour traits and indeed most male secondary traits in many species is poorly understood. In the guppy (Poecilia reticulata), a model species for the study of sexual selection, females often prefer the most colourful males. Little is known about colour vision in this species. My M.Sc work exploited the technique of in situ hybridization to characterize the expression patterns of cone opsins (the genes responsible colour vision) across the surface of the retina in this species, to give further insight into the visual capacity of guppies.