Feeds

Speedy evolution saves blue moon butterflies

Eye blinkingly fast

The Power of One Infographic

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. ®

Eight steps to building an HP BladeSystem

More from The Register

next story
Malaysian Airlines flight MH17 claimed lives of HIV/AIDS cure scientists
Researchers, advocates, health workers among those on shot-down plane
Forty-five years ago: FOOTPRINTS FOUND ON MOON
NASA won't be back any time soon, sadly
Mwa-ha-ha-ha! Eccentric billionaire Musk gets his PRIVATE SPACEPORT
In the Lone Star State, perhaps appropriately enough
MARS NEEDS OCEANS to support life - and so do exoplanets
Just being in the Goldilocks zone doesn't mean there'll be anyone to eat the porridge
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
Diary note: Pluto's close-up is a year from … now!
New Horizons is less than a year from the dwarf planet
Boffins discuss AI space program at hush-hush IARPA confab
IBM, MIT, plenty of others invited to fill Uncle Sam's spy toolchest, but where's Google?
prev story

Whitepapers

Reducing security risks from open source software
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Application security programs and practises
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Consolidation: the foundation for IT and business transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.