Butterfly shows evolution at work Scientists say they have seen one of the fastest evolutionary changes ever observed in a species of butterfly.
The tropical blue moon butterfly has developed a way of fighting back against parasitic bacteria.
Six years ago, males accounted for just 1% of the blue moon population on two islands in the South Pacific.
But by last year, the butterflies had evolved a gene to keep the bacteria in check and male numbers were up to about 40% of the population.
Scientists believe the comeback is due to "suppressor" genes that control the Wolbachia bacteria that is passed down from the mother and kills the male embryos before they hatch.
"To my knowledge, this is the fastest evolutionary change that has ever been observed," said Sylvain Charlat, of University College London, UK, whose study appears in the journal Science.
Rapid natural selection
Gregory Hurst, a University College researcher who worked with Mr Charlat, added: "We usually think of natural selection as acting slowly, over hundreds of thousands of years.
"But the example in this study happened in the blink of the eye, in terms of evolutionary time, and is a remarkable thing to get to observe."
The team first documented the massive imbalance in the sex ratio of the blue moon butterfly (Hypolimnas bolina) on the Samoan islands of Savaii and Upolu in 2001.
In 2006, they started a new survey after an increase in reports of male sightings at Upolo.
They found that the numbers of male butterflies had either reached or were approaching those of females.
The researchers are not sure whether the gene that suppressed the parasite emerged from a mutation in the local population or whether it was introduced by migratory Southeast Asian butterflies in which the mutation already existed.
But they said that the repopulation of male butterflies illustrates rapid natural selection, a process in which traits that help a species survive become more prominent in a population.
"We're witnessing an evolutionary arms race between the parasite and the host. This strengthens the view that parasites can be major drivers in evolution," Mr Charlat said.
The beauty of natural selection. A single gene in only a handful of males that allowed them to survive in a time when they were all dying and look at it now, they're becoming resistant to it. I'd like to hear about the effect on the rate of other genetically linked traits in these survivors. Something like this could have the chance to create a genetic bottle neck in the population, especially if the males that carried this gene carried many negative genetic traits.
I've committed the greatest sin, worse than anything done here today. I sold half my soul to the devil. -Ivan Isaac, the Half Souled Knight
Remember folks, its not evolution. Its natural selection.
Every species has within them the ability to adapt, that doesn't mean its evolved. No sirree. So speaks the non -scientist idiot who thinks they know more than real scientists.
Back on topic, this is cool. Just another example of many to shove in the fundies face.
Never apologise for being a geek, because they won't apologise to you for being an arsehole. John Barrowman - 22 June 2014 Perth Supernova.
Countries I have been to - 14.
Australia, Canada, China, Colombia, Denmark, Ecuador, Finland, Germany, Malaysia, Netherlands, Norway, Singapore, Sweden, USA.
Always on the lookout for more nice places to visit.
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—Abraham Lincoln
People pray so that God won't crush them like bugs.
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Oil an emergency?! It's about time, Brigadier, that the leaders of this planet of yours realised that to remain dependent upon a mineral slime simply doesn't make sense.
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The peppered moth in Northern England is just as good an example. As is the fact that, apparently, a significant fraction of African elephants now don't have tusks.
Another one: Individual humans are remarkably weak, and good prey for carnivores such as lions. Why don't lions eat humans? Because they don't like the taste much, probably. Why don't they like the taste? Because the ones that did died.
You want to see the most lethally efficient pack predator ever known? Look in the mirror.
kinnison wrote:
Another one: Individual humans are remarkably weak, and good prey for carnivores such as lions. Why don't lions eat humans? Because they don't like the taste much, probably. Why don't they like the taste? Because the ones that did died.
Actually that´s not quite true. Every once in a while people who behave dumb enough do get eaten by lions.
There´s even a video of a camara man getting eaten by a pack of lions floating somewhere around in the internet.
kinnison wrote:
Another one: Individual humans are remarkably weak, and good prey for carnivores such as lions. Why don't lions eat humans? Because they don't like the taste much, probably. Why don't they like the taste? Because the ones that did died.
The reasons why most predators don't mess with humans is from way back in the day when mobs of our ancestors used to hunt them. I believe that the parts of africa and asia with megafauna still is where man and said animals existed together and the rest of the continent where most of the megafauna went extinct is where man eventually migrated to and where they typically weren't afraid of man. This probably links to disease and climate change for the reason why most megafauna died off.
I've committed the greatest sin, worse than anything done here today. I sold half my soul to the devil. -Ivan Isaac, the Half Souled Knight
