Are British butterflies getting bigger due to changes in our climate?

Are butterflies getting bigger due to changes in our climate? Winged insects’ body size increases with temperature, study shows

  • The study used digital technology to analyse tens of thousands of specimens
  • They looked at body measurements of 24 UK butterfly species and temperature  
  • 17 in Natural History Museum collection had body size increase with temp

British butterflies are getting bigger due to climate change, research shows.

For the past few decades scientists have observed that winged insects have been steadily increasing in size. 

They decided to establish if there was a link between size and average temperatures.

The study used digital technology to analyse tens of thousands of specimens in the Natural History Museum’s butterfly collection. 

In a comparison of the body measurements of 24 UK butterfly species with monthly temperature records, they found that for 17 of the species, body size increased with temperature. 

British butterflies are getting bigger due to climate change, research shows. Pictured: A Peacock butterfly with wings open

Dr Phillip Fenberg, who co-authored the study at Southampton University, said the difference between cold and warm years is roughly a millimetre in forewing size.

There was also a link at the late larval stages of the insects’ development.

He said: ‘Our paper is among the first to show that computer vision can be applied to these digital images for testing hypotheses on how animals may respond to climate change. 

‘This is accelerating our potential to understand how the biosphere will react to climate change.’ 

The study, which also involved researchers from the Natural History Museum and University of California, follows others showing a link between changing global temperatures and the size of wildlife, although one found that birds might be shrinking in size. 

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