British Butterfly is Evolving to Respond to Climate Change

Brown Argus butterly (A.agestis) on a flower. Courtesy of Vince Massimo

As global temperatures rise and climatic zones move polewards, species will need to find different environments to prevent extinction. New research, published in the journal Molecular Ecology, has revealed that climate change is causing certain species to move and adapt to a range of new habitats.

The study, led by academics at the Universities of Bristol and Sheffield, aimed to understand the role of evolution in helping a species to successfully track ongoing climate change.

With climate warming many species are moving further north in the UK. However, this may mean crossing a landscape with increasingly less of their preferred habitat. Evolutionary change in the ability to use geographically widespread habitats or increased ability to move longer distances can help species to track the warming climate and move northwards.

The Brown Argus butterfly is successfully expanding its distribution northwards in the UK and uses a range of distinct habitats. Using genetic techniques to detect evolutionary change, the researchers were able to show that the colonization of new sites further north by the Brown Argus has involved significant adaptation during or following colonization.

Furthermore, the results suggest that populations of the Brown Argus are adapted to different habitats and that pre-existing variation in habitat preference between populations has been important in allowing the colonization of new habitats.

James Buckley, one of the researchers from the University’s School of Biological Sciences, said, “To our knowledge, this is one of the first studies to identify genetic evidence for evolutionary change associated with range shifts driven by recent climate change.”

The study, which is funded by the Natural Environment Research Council (NERC), found that evolutionary change is likely to affect the success of species’ responses to climate change and that maximizing genetic variation in ecological traits (such as habitat preference) across species’ distributions should help species to move northwards and track the changing climate across a fragmented landscape.

James added, “These findings are important as understanding the likelihood and speed of such adaptive change is important in determining the rate of species extinction with ongoing climate change.”