NERC GW4+ DTP PhD studentship: Evolutionary consequences of cultural niche construction

Supervisors:

Dr Alex Thornton, College of Life and Environmental Sciences, University of Exeter
Dr Alastair Wilson, College of Life and Environmental Sciences, University of Exeter
Dr Jon Bridle, School of Biological Sciences, University of Bristol

Project description:

Social learning, the ability to learn from others, can have major ecological and evolutionary implications by promoting the spread of adaptive information within and between generations and generating cultural differences between populations. Theoretical models suggest that by allowing organisms to alter their environments and enter new niches, culturally transmitted traits can modify selection pressures and thereby influence genetic evolution1. However, while such cultural niche construction is increasingly recognised as a major factor in human evolution, its importance in other species has yet to be examined. There is thus an urgent need for empirical research to determine the consequences of cultural transmission in nature.
The only well-documented case of culturally-facilitated niche invasion occurred when black rats entered newly-planted pine forests in Israel in the 1950s and 1960s. Here there is strong experimental evidence that the ability to extract seeds from pine cones was transmitted by social learning from mothers to offspring, enabling rat populations to become established in the previously unoccupied forest niche2. Pine cones constitute the only source of food within forests and rats from non-forest populations are typically unable to learn efficient pine-cone stripping through trial and error in the absence of knowledgeable models2. Dispersal into the forests from surrounding areas is therefore likely to be extremely limited, leading to genetic differentiation and differential selection in forest and non-forest populations. In particular, one may predict that forest populations may have come under selection for morphological adaptations to a more arboreal lifestyle and improved learning abilities to maximise skill acquisition. Using this unique system, the project will examine the evolutionary repercussions of cultural niche construction for the first time in non-human animals. Specifically, it will:

1. Determine whether the culturally-facilitated invasion of pine plantations has led to genetic divergence between forest and adjacent non-forest populations
2. Use morphometric measurements and learning experiments to examine phenotypic divergence in morphological and cognitive traits between populations
3. Use models from quantitative genetics to determine the role of selection in generating adaptive genetic and phenotypic differences between populations

The student will work with established Israeli partners to trap and sample rats and run experiments to compare social learning abilities in rats from forest and adjacent non-forest populations. Genetic analyses of tissue samples will use state-of-the art facilities in Exeter and Bristol. Together this work will make a major contribution to our understanding of the role of cultural processes in driving evolutionary change.

Training opportunities:

The student will receive training in the following areas (details of facilities given in brackets):

• Evolutionary theory, particularly theoretical advances in gene-culture coevolution and cultural niche construction; comparative psychology and social learning theory
• Design of learning experiments (training by Dr Alex Thornton; experimental facilities provided by project partners at the University of Tel Aviv)
• Mammal trapping, handling and tissue-sampling (training and tissue storage facilities provided by project partners at the University of Tel Aviv)
• Molecular genetics: including DNA extraction; PCR; microsatellite genotyping (necessary laboratory facilities available at the Universities of Exeter and Bristol)
• Statistics, including use of population and quantitative genetic models (necessary computing facilities available at the University of Exeter, Penryn Campus)

Interdisciplinary aspects:

This is a highly interdisciplinary project integrating evolutionary biology, molecular genetics and comparative psychology. It will use cutting edge techniques in molecular and quantitative genetics to explore questions at the interface of ecology and evolution and thus falls firmly within the NERC remit. Specifically, the proposal bridges three key research themes:

(1) “Genomes and evolution”: exploring cultural transmission as a driver of evolutionary change
(2) “Ecology, conservation and biodiversity”: examining the effects of cultural transmission on dispersal patterns and niche invasion in free-living animal populations
(3) “Climate change and impacts”: determining the role of cultural processes in enabling animals to exploit new resources and cope with changing environments.

Unlike previous research in these areas, the project incorporates the role of cognitive processes typically studied by psychologists and is informed by theoretical models of cultural niche construction and gene-culture coevolution emerging from evolutionary anthropology. The combination of these approaches will generate unique insights into the evolutionary and ecological consequences of cultural processes.

For further information, please visit http://www.exeter.ac.uk/studying/funding/award/?id=1369