One of the most profound challenges we all face is our deterioration with age - a process known as senescence. Individuals clearly senesce differently, as they start to deteriorate at different ages and some individuals decline quicker than others. However, our understanding of why individuals senesce differently remains limited. In particular, little is known about whether individual characteristics (e.g. morphological, physiological, immunological or reproductive traits) start to senesce at the same age or rate, and how complex, interacting environmental and genetic factors impact on how these traits senesce in natural populations. To devise better medical and veterinary treatments it is crucial to improve our understanding of the internal (cellular, genetic) and external (environmental) basis of individual differences in senescence. This will provide insight into why some individuals are less able to buffer against senescence, perhaps, for example, due to their genetic makeup (e.g. reduced resistance to oxidative damage) or because of the impact of a poor early-life environment on their development.
This PhD will investigate the relative impact of environmental and genetic factors on senescence using the model Seychelles warbler system. Seychelles warblers are subject to variable environmental effects and show considerable differential senescence. The PhD student will have access to this exceptional Seychelles warbler study population and the associated long-term dataset and genetic pedigree, gaining skills in fieldwork, microscopy, genomics, quantitative genetics and statistics. For example, path analysis will be used to determine the relationships between environmental and genetic effects on the senescence of multiple traits, while next-generation sequencing will provide genomic resources to infer inbreeding and determine its effect on senescence. Molecular and statistical skills are an advantage, but training will be provided. The student will benefit from interactions with all members of Seychelles Warbler Project (http://seychelles-warbler-project.group.shef.ac.uk
) and a vibrant academic environment at the University of Leeds, including training programs through LeedsOmics (http://www.leedsomics.org
The successful student will work with researchers at the Universities of Leeds, East Anglia, Sheffield and Groningen to investigate individual variation in senescence. The student will address the following fundamental questions in evolutionary biology:
1. Do individuals differ in the onset and rate of the senescence of morphological, immunological, physiological and reproductive traits?
2. Within-individuals, is there synchrony of senescence across functionally similar traits?
3. What is the relative impact of genetic and environmental effects on senescence?
This will improve our understanding of how and why some individuals live longer, healthier lives, and provide insight into mitigating senescence.
Applicants must hold a 2.1 Honours or Masters degree in a relevant subject, and have a keen interest in molecular ecology and life-history evolution. Previous experience of bird ringing, fieldwork in harsh environments, molecular techniques, Access databases and statistics would be beneficial; however, excellent training will be provided (e.g. http://www.fbs.leeds.ac.uk/postgraduate/professionaldev.php
). The student will be required to conduct fieldwork for a minimum of three seasons (up to 3 months per season).
The student will be supervised by Dr Hannah Dugdale (Leeds), Amanda Bretman (Leeds) and Prof David S Richardson (East Anglia). They will also collaborate with Dr Alex Sparks (Leeds), Prof Terry Burke (Sheffield) and Prof Jan Komdeur (Groningen).
Bebbington K, Spurgin LG, Fairfield EA, Dugdale HL, Komdeur J, Burke T & Richardson DS. 2016. Telomere length reveals cumulative individual and transgenerational inbreeding effects in a passerine bird. Molecular Ecology, 25, 2949-2960
Edwards HA, Burke T, Dugdale HL (2017) Repeatable and heritable behavioural variation in a wild cooperative breeder. Behavioral Ecology, 28, 668–676
Hadfield JD, Richardson DS & Burke T (2006) Towards unbiased parentage assignment: combining genetic, behavioural and spatial data in a Bayesian framework. Molecular Ecology, 15, 3715–3730.
Hammers M, Kingma SA, Bebbington K, van de Crommenacker J, Spurgin LG, Richardson DS, Burke T, Dugdale HL, Komdeur J (2015) Senescence in the wild: Insight from a long-term study on Seychelles warblers. Experimental Gerontology, 71, 69–79 www.sciencedirect.com/science/article/pii/S0531556515300425
Leech T, Sait SM, Bretman A (2017) Sex-specific effects of social isolation on ageing in Drosophila melanogaster Journal of Insect Physiology, 102, 12-17