Can wild insects adapt to climate change by changing their behaviour?
Main supervisor: Prof Tom Tregenza
Co-supervisor(s): Dr Jon Bridle (University of Bristol)
Contact number: 01326 371862
Host institution: University of Exeter
CASE Partner: Chelonia Limited
Climate change poses a profound threat to biodiversity. The capacity of living organisms to cope with changing thermal regimes therefore demands urgent attention. This studentship is to conduct a study using a wild insect population in a meadow in the north of Spain. The successful student will quantify the extent of variation in behavioural thermoregulatory behaviour, its evolutionary potential, and the strength and variation of selection on this behaviour.
Theoretical studies predict significant impacts of global warming on insect biodiversity. However, these studies often lack information about the behavioural adaptions that might equip animals to cope with variable temperatures (1: Maino et al 2016). We need answers to questions like:
• What thermoregulatory challenges do insects face in their natural environment?
• How do individuals use behaviour to cope with changes in temperature in the wild?
• How much among-individual variation in behavioural thermoregulation exists in natural populations?
• How much of the variation in behavioural thermoregulation is heritable, and hence provides the potential for evolutionary adaptation?
• How strong is selection on behavioural thermoregulation in natural populations?
• Do the strength and/or direction of selection on behavioural thermoregulation vary among years in natural populations?
The studentship will exploit our 10 year study (www.wildcrickets.org) of a natural population of field crickets (Gryllus campestris) (2: Rodríguez-Muñoz et al 2010) to answer these questions. We have genetic measures of reproductive success and detailed behavioural information from ten years of video from up to 140 cameras recording simultaneously. These data will allow the student to retrospectively extract detailed information on thermoregulatory behaviour and estimate heritability and effects on fitness.
A combination of actual temperature measurements under different microhabitat conditions (sun and shade), behavioural observations of wild crickets obtained from video data, and environmental variables will be used to parameterise a predictive thermal model. This will make it possible to estimate individual body temperatures from video data and environmental variable measurements.
This approach will allow the student to identify the extent to which individual crickets use behaviour to thermoregulate in their natural environment and to quantify variation in the expression of this trait. DNA fingerprinting data means that we can accurately assign offspring to their parents, so providing a measure of lifetime reproductive success. This detailed data on variance in behavioural traits, and their relation to fitness in natural populations, will provide the student with some of the first data to test the potential for selection to drive evolutionary change in behavioural thermoregulation.
1. Maino JL, Kong, JD, Hoffmann et al. (2016). Current Opinion in Insect Science, 17: 1-6.
2. Rodríguez-Muñoz, R., Bretman, A., Slate, J., Walling, C. & Tregenza, T. Science 328, 1269–1972 (2010).