About the project

The evolutionary consequences of climate change are likely to be widespread, but are little understood. In particular, what happens when closely related species which used to be geographically separated come into contact as a result of climate-driven shifts to their distributions?

This PhD will research a model system of hybridisation due to climate change - as it happens. The brown argus butterfly (Aricia agestis) has moved northwards in Britain since the 1980s and has recently colonised parts of the distribution of the northern brown argus (Aricia artaxerxes). This studentship will examine the extent to which hybridisation between the two Aricia species is taking place, the evolutionary consequences of this, and ultimately assess the likelihood of survival of the northern species.

A background in evolutionary genetics and conservation would be useful, together with an interest in understanding the evolutionary consequences of global change.

Map of Great Britain showing the distributions of the univoltine Northern brown argus, Aricia artaxerxes (blue squares), and the bivoltine brown argus, Aricia agestis (red and pink squares).

Red squares: records of A. agestis from 1970-1987 when geranium use was uncommon).

Pink squares: new expanded range of A. agestis where geranium use is widespread.

Project objectives

  • Quantify how the number of butterfly generations per year and their use of host plants have changed (phenotypic changes) since ~1900.

  • Estimate the extent of gene flow between the two species.

  • Identify genes involved in new adaptations to host plants and the number of generations per year, and evaluate whether adaptive genes are passing between the two species.

  • Estimate rates of expansion and gene flow, and assess whether the northern species might be genetically replaced by the southern species with further warming.

Supervisory team

  • Main supervisor: Dr Kanchon Dasmahapatra (Leverhulme Centre for Anthropocene Biodiversity, Department of Biology, University of York)
  • Co-supervisor: Dr Rachel Pateman (Stockholm Environment Institute, Department of Environment and Georgraphy, University of York)
  • Co-supervisor: Dr David Roy (Biological Records Centre, Wallingford, UK Centre for Ecology and Hydrology)
  • Co-supervisor: Dr Simon Duffield (Natural England)
  • Co-supervisor: Prof Chris Thomas (Leverhulme Centre for Anthropocene Biodiversity, Department of Biology, University of York)

Excellent training opportunities and research environment

The project will involve fieldwork in Britain, lab work, and the bioinformatic analysis of genome sequences. You will benefit from using high quality genome assemblies from the Darwin Tree of Life Project and ecological data from the UK Biological Records Centre and Butterfly Conservation. You will benefit from access to York’s dynamic research centres, the Leverhulme Centre for Anthropocene Biodiversity and the Stockholm Environment Institute.

Natural England is a CASE partner for this project, and will provide supervision, additional resources for fieldwork, and policy or conservation-based placement opportunities.

Addition training opportunities are provided through the NERC ACCE DTP and NERC Advanced Short Training courses.

Biological Sciences is ranked in the top 10 overall in the UK. The Department of Biology has held an Athena SWAN Gold award since 2014, and the ethos is to support all staff and students to reach their full potential, and .


The project is funded by the NERC ACCE DTP. The funding covers 3.5 years of stipend (£18,622 per year in 2023/24), university fees and research expenses. Additional fieldwork expenses will be provided by Natural England and Butterfly Conservation Yorkshire.

Both UK and non-UK candidates are eligible for this funding.

Relevant publications

Buckle J & Bridle JR (2014) Loss of adaptive variation during evolutionary responses to climate change. Ecology Letters 17: 1316– 1325.

Buckley J, Butlin RK & Bridle JR. (2012), Evidence for evolutionary change associated with the recent range expansion of the British butterfly, Aricia agestis, in response to climate change. Molecular Ecology, 21: 267-280.

Pateman RM, Jane K Hill, David B Roy, Richard Fox, Chris D Thomas (2012) Temperature-dependent alterations in host use drive rapid range expansion in a butterfly. Science 336: 1028-1030.

Mallet J, Wynne IR & Thomas CD (2011), Hybridisation and climate change: brown argus butterflies in Britain (Polyommatus subgenus Aricia). Insect Conservation and Diversity, 4: 192-199.

How to apply

Both UK and non-UK candidates are eligible to apply for this project. Click here to apply. Applications are open from 21 October 2023 till 8 January 2024.

For further information please email