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ENV East Doctoral Training Partnership

 

Applications to the EnvEast Doctoral Training Partnership are now closed.

Below you can browse some of the PhD projects we have previously funded; if you would like to be informed when applications open, or if you have any questions about EnvEast and our application process, please email us.

Projects previously funded by EnvEast

RICHARDSON_U14EE

Evolving with pathogens: how pathogens drive genetic diversity over space and time in an endemic island bird

Project description

Genetic diversity is key to the adaptive potential of species and populations, affecting their ability to respond, adapt and avoid extinction in the face of future challenges. How genetic diversity is generated and maintained in natural populations, especially small and/or fragmented ones, is therefore a fundamental question for population and conservation ecologists.

Nowhere is diversity more important than at genes that underpin the immune system. Only by measuring how pathogens and immune genes co-vary over space and time can we understand the mechanisms that drive variation at these critical genes. Although studies have investigated variation in pathogen-mediated selection (PMS) between populations, few have addressed the scale at which selection can occur within a population. Recent work, showing that changes in PMS are important over fine landscape scales of just a few hundred meters, suggests this may be of considerable ecological and evolutionary importance. Fewer studies still have incorporated a temporal component into their analyses.

Previous studies have revealed that Berthelot’s pipit was bottlenecked as it colonised the Canary Islands and spread northwards to Madeira and the Selvagens. However variation at certain immune genes appears to have regenerated rapidly since then. Moreover, the pathogens infecting pipits have been found to differ consistently across islands and, importantly, at the landscape scale within Tenerife. This study will focus on variation within two gene families central to the innate immune response. Toll-like receptor genes produce molecules which mediate innate immune responses by recognising pathogens. Beta-defensin genes produce anti-microbial peptides that directly attack invading pathogens. This system provides an excellent opportunity to investigate how and why adaptive genetic variation changes over time, at both the population and the landscape scale, within a natural population.

  • Start date 1 October 2014