The 2019 QUEX PhD candidates are working on the following projects. Please note, these positions have been filled.

12. How do nutritional interventions affect male and female ageing rates?: an experimental genomic approach

UQ academic lead

Associate Professor Steve Chenoweth, School of Biological Sciences

Exeter academic lead

Professor Alastair Wilson, Professor of Evolutionary Biology, College of Life and Environmental Sciences

Project description

Senescence, where individuals decline in survival probability and reproductive output with age, is a phenomenon found right across the tree-of-life. Understanding, and often trying to delay, this phenomenon is an important area of human biomedical research, which focuses largely on identifying proximate risk factors – both intrinsic, like genetic mutations or chromosome telomere length, and environmental such as nutrition and exercise. However, the ubiquity of senescence across animal species has also long fascinated evolutionary biologists. If senescence is bad for fitness, why does it persist despite natural selection, and why are rates of senescence variable within- and between populations?

This Exeter–UQ collaborative research project seeks to address fundamental questions about the causes senescence in a way that combines these proximate (mechanistic) and ultimate (evolutionary) viewpoints. It will take an experimental approach to understanding why individuals and genders differ in the speed with which they age. Specifically, the project will dissect the relationship between an individual’s diet, variations in its personal genome and ageing outcomes.

To achieve this, the student will use a powerful experimental genomic system developed at the University of Queensland in the lab of A/Prof Steve Chenoweth. A comprehensive set of genomic resources are now available for an emerging model insect system that permits experimental investigations of ageing. These include panels of more than 100 sequenced living genomes, and a panel of 100 of mutation accumulation lines. This will allow the student to investigate how new mutations shape individual ageing trajectories, and critically determine whether harmful mutational effects can be offset through targeted dietary interventions. These genomic tools will be combined with an evolutionary approach, rooted in life-history models that give clear and general predictions about when, why and how senescence should occur. To test these predictions genomic and genetic data will be investigated using modelling and analysis techniques developed in the group of Prof Wilson at the University of Exeter.

This project, therefore, offers students a rare opportunity to acquire a broad understanding of evolutionary biology and life-history theory, a well as specific skills in statistical genetics, bioinformatics and the experimental techniques used in nutritional research. This broad training will allow them to develop their own innovative research programmes in fundamental and/or applied areas of biology – from tackling today’s emerging human and animal health problems, to understanding life-history variation in natural populations.

The student will divide their time between experimental design, theoretical modelling and data analysis at the University of Exeter (Wilson), and experimental genomic work at the University of Queensland (Chenoweth).