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Research Fellows Directory

Jarrod Hadfield

Dr Jarrod Hadfield

Research Fellow


University of Edinburgh

Research summary

Individuals of the same species often differ depending on where they live. Part of these differences are genetic differences that have accumulated because they allow individuals to survive and reproduce better in the location they were born. However, some of the differences are environmental and reflect the direct action of environmental variables, such as temperature, on aspects of the individuals morphology and behaviour. To tell which is more important - genetic or environmental differences - scientists often have to move individuals between locations and see how they, or their offspring, change. While these types of experiments are possible for some types of animals and plants for others, such as birds, they are more difficult. However, when people have measured individuals at different locations, and at different times at the same location, it is possible to distinguish environments from genetic effects without having to move individuals. Using mathematical models I have shown how this is possible and how it is also possible to use similar data to measure what characteristics are best in which environments. With collaborators I then applied these mathematical models to large data sets collected by citizen scientists across the UK. The first collaboration showed that differences in when birds lay their eggs (earlier in the south, later in the north) is primarily due to a direct response to the environment, potentially temperature. In contrast, differences in when plants flower or come into leaf are sometimes the result of genetic differences and sometimes the result of environmental differences depending on the species.

Interests and expertise (Subject groups)

Grants awarded

The Quantitative Genetics of Evolutionary Stasis

Scheme: University Research Fellowship

Dates: Jan 2017 - Dec 2019

Value: £297,334.28

Evolutionary Rate: Micro to Macro

Scheme: University Research Fellowship

Dates: Jan 2012 - Dec 2016

Value: £482,637.24