Runaway sexual selection- catching the genes.
Dr Domino Joyce (UoH), Dr Martin GennerContact email: firstname.lastname@example.org
Sexual selection has generated an incredible amount of biodiversity. The idea that exaggerated male traits and female choice for those traits become associated to produce runaway sexual selection is widely accepted. In the nearly 90 years since Fisher proposed this though, the genetic mechanisms remain elusive, despite the genomics revolution of the last ten years or so. A major challenge in biology is therefore evaluating the wealth of models which predict how biodiversity could be generated by sexual selection, with empirical examples using known “sexual selection loci”. Understanding the genetic changes which can lead to runaway sexual selection would allow us to better understand how a substantial proportion of life on earth evolved.
A well established model for studying genetics, evolution and behaviour are the cichlid fish of Lake Malawi. Approximately 1000 species of fish have evolved in less than 5 million years, showing an incredible array of ecologically and sexually selected adaptations, and there are many genomic resources available. Studies in our lab have identified a genomic region associated with a fascinating sexually selected behaviour - the shape of underwater sand-castles (“bowers”) that male fish build in order to impress females, and we are now in a position to explore and verify this experimentally. This system is ideal for studying sexual selection and mate choice because i) fish build bowers and mate in large pools in captivity ii) individuals can be identified using PIT tags iii) bower manipulation or substitution is possible iv) cichlid fish are maternal mouth brooders and offspring can be DNA paternity tested v) genomic studies have identified candidate genes responsible for varying bower shapes vi) we already have 15 genomes from 3 related species waiting to be analysed vii) we are developing CRISPR-cas9 gene editing in these species.
We are looking for a PhD student who wants to broaden their experience in bioinformatics and fish husbandry to explore the genetic basis of the sexually selected loci responsible for these traits, using genomics and laboratory experiments to identify and verify the causes of phenotypic change.
Related undergraduate subjects:
- Molecular ecology