Feeds

Speedy evolution saves blue moon butterflies

Eye blinkingly fast

High performance access to file storage

Researchers on the island of Samoa have witnessed evolution in action, as the population of male "Blue Moon" butterflies has returned from the brink of extinction. The researchers, from Berkeley University, put the resurgence of the species down to an evolutionary arms race, in which the butterflies' latest weapon is a gene that fights off a parasite.

The male 'Blue moon' butterfly. Image credit: Sylvain Charlat

The male 'Blue moon' butterfly. Image credit: Sylvain Charlat.

Six years ago, the male Blue Moon butterflies made up just one per cent of the species. The cause was a parasitic bacteria, Wolbachia. The bacteria is passed down by the mother and selectively kills male butterflies before they have a chance to hatch.

But despite continued infection with the bacteria, the males of the species are now back at 40 per cent of the total population.

The key lies in a gene that holds the bacteria in check. The gene is so successful that it spread throughout the entire population of butterflies within 10 generations - over the course of a year, according to the paper published in the 13 July edition of Science.

"To my knowledge, this is the fastest evolutionary change that has ever been observed," said Sylvain Charlat, lead author of the study and a post-doctoral researcher with joint appointments at the University of California, Berkeley, and University College London.

"This study shows that when a population experiences very intense selective pressures, such as an extremely skewed sex ratio, evolution can happen very fast."

The team is not certain of the origins of the saviour gene. It could have emerged through random mutation, or it could have been introduced into the population by a migrating butterfly.

"Regardless of which of the two sources of the suppressor gene is correct, natural selection is the next step. The suppressor gene allows infected females to produce males, these males will mate with many, many females, and the suppressor gene will therefore be in more and more individuals over generations," said Charlat.

The researchers say the discovery illustrates how quickly a species can respond to an evolutionary pressure and, more generally, how important parasites might be as an evolutionary force. ®

High performance access to file storage

More from The Register

next story
Fancy joining Reg hack on quid-a-day challenge?
Recruiting now for charity starvation diet
Red-faced LOHAN team 'fesses up in blown SPEARS fuse fiasco
Standing in the corner, big pointy 'D' hats
KILLER SPONGES menacing California coastline
Surfers are safe, crustaceans less so
Opportunity selfie: Martian winds have given the spunky ol' rover a spring cleaning
Power levels up 70 per cent as the rover keeps on truckin'
Discovery time for 200m WONDER MATERIALS shaved from 4 MILLENNIA... to 4 years
Alloy, Alloy: Boffins in speed-classification breakthrough
Elon Musk's LEAKY THRUSTER gas stalls Space Station supply run
Helium seeps from Falcon 9 first stage, delays new legs for NASA robonaut
Top Secret US payload launched into space successfully
Clandestine NRO spacecraft sets off on its unknown mission
prev story

Whitepapers

Top three mobile application threats
Learn about three of the top mobile application security threats facing businesses today and recommendations on how to mitigate the risk.
Combat fraud and increase customer satisfaction
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Five 3D headsets to be won!
We were so impressed by the Durovis Dive headset we’ve asked the company to give some away to Reg readers.
SANS - Survey on application security programs
In this whitepaper learn about the state of application security programs and practices of 488 surveyed respondents, and discover how mature and effective these programs are.