Friday, July 13, 2007

Evolution at work, maybe

From the comment section in Vox Day's blog, I was pointed to this article in the BBC News site. The headline reads Butterfly shows evolution at work. It says
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.
My emphasis. Now the impression one gets from the article is that the blue moon butterly (Hypolimnas bolina) developed a brand new gene in less than 6 years. A blink, nay, a micro-blink of an eye in evolutionary time scales. Evolution at work indeed, on the express lane. Needless to say, biologists are pretty excited.

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."
Indeed it is. IF it is what they say it is, that is, if it indeed a new gene that developed that quickly in response to the bacteria, as the first breathless paragraphs of the article seem to be saying. But

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.
Right. It might not be a new gene after all. They have to examine other populations of the butterfly first to make sure that the gene does not exist in those populations. So the headline should say Evolution at work... maybe. We're still checking. The article reports rapid natural selection as if it were a remarkable thing. It isnt. An epidemic would wipe out individuals that arent resistant to the disease, and leave those with resistance to breed, and the epidemic could do that quite rapidly indeed. What would be remarkable is if they somehow determine that the gene is indeed new, because that could indicate that a specific code was developed as a response to the bacteria.

I dont know if this article is unwitting propaganda in the ongoing battle between the Darwin adherents and their opponents or is just simple tabloid sensationalism, the kind like this one here.

Update (16 July 2007): The link I provided to CNN's squid story in the last paragraph above has since been corrected. It now reads 'Huge squid washes up on beach' instead of 'Bus-sized squid...'.


Baldagyi Hatipoglu said...

saw this news bit but too busy to comment. so it turns out there's no genetic mutation involved. ang labo! the news' headline was misleading

Jego said...

To be fair, there's still the possibility that it is indeed a new gene, but the data does not support such a conclusion at this point, even though the article gives that impression. Boooo!

By the way, in the link I provided to CNN's squid story, it seems CNN has corrected the headline. It now reads 'Huge squid washes up on beach' instead of 'Bus-sized squid...'.