Feeds

Speedy evolution saves blue moon butterflies

Eye blinkingly fast

Intelligent flash storage arrays

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. ®

Intelligent flash storage arrays

More from The Register

next story
MARS NEEDS WOMEN, claims NASA pseudo 'naut: They eat less
'Some might find this idea offensive' boffin admits
LOHAN crash lands on CNN
Overflies Die Welt en route to lively US news vid
Comet Siding Spring revealed as flying molehill
Hiding from this space pimple isn't going to do humanity's reputation any good
Experts brand LOHAN's squeaky-clean box
Phytosanitary treatment renders Vulture 2 crate fit for export
Boffins who stare at goats: I do believe they’re SHRINKING
Alpine chamois being squashed by global warming
No sail: NASA spikes Sunjammer
'Solar sail' demonstrator project binned
Carry On Cosmonaut: Willful Child is a poor taste Star Trek parody
Cringeworthy, crude and crass jokes abound in Steven Erikson’s sci-fi debut
prev story

Whitepapers

Cloud and hybrid-cloud data protection for VMware
Learn how quick and easy it is to configure backups and perform restores for VMware environments.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Three 1TB solid state scorchers up for grabs
Big SSDs can be expensive but think big and think free because you could be the lucky winner of one of three 1TB Samsung SSD 840 EVO drives that we’re giving away worth over £300 apiece.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.