Gourmet butterflies speed north: study

May 24, 2012

A new study led by scientists in the Department of Biology at the University of York has shown how a butterfly has changed its diet, and consequently has sped northwards in response to climate change. Their study is published in the latest issue of Science.

The researchers found that warmer summers have allowed the Brown Argus butterfly to complete its by eating wild Geranium plants. Because the Geraniums are widespread in the British countryside, this change in has allowed the butterfly to expand its range in Britain at a surprisingly rapid rate. Over the past 20 years, the Brown Argus has spread northwards by around 79 kilometres and has become common in the countryside in much of southern England.

Lead author PhD student Rachel Pateman, of the University of York's Department of Biology and the NERC Centre for Ecology & Hydrology, said: "Many are shifting their distributions northwards as the climate warms, but this previously scarce species has surprised everyone by moving its range at over twice the average rate."

Co-author Chris Thomas, Professor of Conservation Biology at York, said: "Because wild Geraniums are widespread in the landscape, the can now move from one patch of host plants to next and hence move rapidly through the landscape – expanding their range generation after generation."

Co-author David Roy, from the NERC Centre for Ecology & Hydrology, said: "The change in diet represents a change to the interactions between species – in this case between a butterfly and the plants that its caterpillars eat – caused by climate warming. Changes to the interactions between species are often predicted to alter the rate at which species shift their distribution in response to climate change; and now we have demonstrated this in nature."

In the 1980s the butterfly was considered scarce in Britain, with populations undergoing continued decline but it has subsequently undergone a dramatic reversal of fortune. The team put this down to the effect of climate on the ability of the butterfly to use additional food plant species.

In the 1980s, the caterpillars were mainly confined to Rockrose plants growing on the chalk hills of southern England, but the use of plant species in the Geranium family has increased as summer temperatures have increased. Wild Geraniums are suitable food plants for the caterpillars in warm years, but not in colder summers. This seems to be because the plants grow in different places, which provide different microclimates. Common Rockrose is found mainly on hot south-facing slopes, where the butterfly can complete its life cycle even in cool summers. This is not the case for the Geraniums and so they only become suitable for the butterfly when summers are warm.

Co-author Richard Fox, from the charity Butterfly Conservation, said: "It is important that we understand how and why species are responding to climate change. Such research would not be possible without the thousands of records of butterflies our dedicated volunteers have collected over many decades, which have allowed us to detect these long term changes."

Rachel Pateman said: "This study has highlighted that species do not respond to climate change in isolation, and that climate change affects how species interact with one another. In the case of the Brown Argus butterfly, changes in interactions with its food plants have helped it to respond to climate change very rapidly. However, changes to interactions may hinder other species, potentially putting them at risk of extinction."

Co-author Professor Jane Hill, of the Department of Biology at the University of York, said: "There will be winners and losers from . It is important that we begin to understand how the complex interactions between species affect their ability to adapt to change so we can identify those that might be at risk and where to focus conservation efforts."

Explore further: Invasive vines swallow up New York's natural areas

More information: The paper ‘Temperature-dependent alterations in host use drive rapid range expansion in a butterfly’ by Rachel M. Pateman, Jane K. Hill, David B. Roy, Richard Fox and Chris D. Thomas is published in Science, on Friday, 25 May 2012.

Related Stories

Climate adaptation difficult for Europe's birds

Jan 17, 2012

Åke Lindström is Professor of Animal Ecology at Lund University, Sweden. Together with other European researchers he has looked at 20 years' worth of data on birds, butterflies and summer temperatures. During this ...

Recommended for you

Invasive vines swallow up New York's natural areas

6 hours ago

(Phys.org) —When Antonio DiTommaso, a Cornell weed ecologist, first spotted pale swallow-wort in 2001, he was puzzled by it. Soon he noticed many Cornell old-field edges were overrun with the weedy vines. ...

Citizen scientists match research tool when counting sharks

21 hours ago

Shark data collected by citizen scientists may be as reliable as data collected using automated tools, according to results published April 23, 2014, in the open access journal PLOS ONE by Gabriel Vianna from The University of Wes ...

Researchers detail newly discovered deer migration

Apr 23, 2014

A team of researchers including University of Wyoming scientists has documented the longest migration of mule deer ever recorded, the latest development in an initiative to understand and conserve ungulate ...

How Australia got the hump with one million feral camels

Apr 23, 2014

A new study by a University of Exeter researcher has shed light on how an estimated one million-strong population of wild camels thriving in Australia's remote outback have become reviled as pests and culled ...

Former Iron Curtain still barrier for deer

Apr 23, 2014

The Iron Curtain was traced by an electrified barbed-wire fence that isolated the communist world from the West. It was an impenetrable Cold War barrier—and for some inhabitants of the Czech Republic it ...

Humpback protections downgrade clears way for pipeline

Apr 22, 2014

Environmentalist activists on Tuesday decried Canada's downgrading of humpback whale protections, suggesting the decision was fast-tracked to clear a major hurdle to constructing a pipeline to the Pacific ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet May 24, 2012
Odd how Biologists see all manner of plants and animals shifting their habitats north or to higher elevations on mountainsides in order to maintain a similar climate niche, and yet failed Libertarian/Randite Economists from industry propaganda groups like the Cato Institure, the Competitive Enterprise Institute, The American Enterprise Institute, the Heritage Institute, etc, all claim that the observed warming isn't politically happening.

More news stories

Genetic code of the deadly tsetse fly unraveled

Mining the genome of the disease-transmitting tsetse fly, researchers have revealed the genetic adaptions that allow it to have such unique biology and transmit disease to both humans and animals.

Ocean microbes display remarkable genetic diversity

The smallest, most abundant marine microbe, Prochlorococcus, is a photosynthetic bacteria species essential to the marine ecosystem. An estimated billion billion billion of the single-cell creatures live i ...

Engineered E. coli produces high levels of D-ribose

D-ribose is a commercially important sugar used as a sweetener, a nutritional supplement, and as a starting compound for synthesizing riboflavin and several antiviral drugs. Genetic engineering of Escherichia co ...