On science blogs this week: Evolution in action

E.O. (Sociobiology) Wilson has revised evolutionary theory in 2010's most important paper, as new kinds of bacteria were eating up that oil plume in the Gulf, just as the government said. Plus MIT's oil-cleaning robots, and introducing Scienceblogging.org.

 

[We have an RSS feed. No orange icon, but click here. If that doesn't work, the URL is http://www.nasw.org/rss.xml]

EVOLUTION IN ACTION, THE REVISED VERSION I. My nominee for this year's most important paper has just appeared in Nature: "The evolution of eusociality" by Martin A. Nowak, Corina E. Tarnita, and Edward O. Wilson (466:1057, doi:10.1038). It's a formal (i.e., mathematical) rejection of kin selection theory. Kin selection? Wikiversity's definition of kin selection has the virtue of simplicity: "the evolutionary tendency to help people who have our genes." Except that the paper argues that kin selection is not an evolutionary tendency.

Kin selection has for decades has been the prevailing hypothesis about the evolutionary origins of altruism and eusociality. (Nature definies eusociality thus: "A life-history strategy in which only a subset of members of a group produce their own offspring, and others act as non-reproductive helpers, as in honeybees or naked molerats.")

The paper shows mathematically that ordinary evolutionary theory is enough to explain the emergence of eusociality. Several steps are involved, so its appearance will be a rare event. But once it occurs, eusociality is a winning strategy; eusocial species like ants, the Wilson model organism, are major success stories. As the press release from Harvard notes, "The biomass of ants alone composes more than half that of all insects, exceeding that of all terrestrial nonhuman vertebrates combined." (Homo sap is regarded as being sorta kinda eusocial.) See Brandon Keim's description of what's in the paper at Wired Science.

The paper has just appeared, so there hasn't been much time for commentary-type blogging yet. As I write, the two major posts are from Dienekes' Anthropology Blog and Gene Expression. They focus on a scholarly question that I find deeply uninteresting, but maybe you'll be fascinated. To wit, Does this paper represent a change of heart for E.O. Wilson, arguably our star public scientist?

Dienekes argues that Wilson used to be a kin selectionist but began to espouse group selection recently. (Let's go with Nature's definition again, this time for group selection: "Selection on traits that increase the relative fitness of populations or lineages of organisms at some fitness cost to individuals.") At Gene Expression, Razib Khan insists that Wilson has been a closet group selectionist all along, and quotes Hindu Scripture from the Wilson Founding Document of 1975, Sociobiology, to prove it.

Booooorrrring.

Perhaps something more compelling will be blogged in the next few days and we can catch up next week. It's really hard to overstate how important this potential change in scientific theory could be. For evolution as a study subject and a science, yes, but I'm thinking chiefly of the impact on discussions about — and research on — all kinds of human behavior. Everything from parenting styles to consumerism, to say nothing of gigantic topics like war and religion.

EVOLUTION IN ACTION, THE REVISED VERSION II. I looooove writing this item, suggesting as it does that scientific conflicts can be resolved without rancor, that our government is not lying to us, that once again evolution gives very visible evidence that it's on the job.

It's a tale that blends a great policy story with a great science story and leads to a happy ending for all. (Except maybe for citizens who lose faith in scientists, the government, and journalists because we haven't explained well enough that, in the real world, statements by scientists, the government, and journalists (and bloggers!) are provisional, subject to amendment, correction, and sometimes even jettisoning altogether. As we shall see.)

In short, it looks as if the various studies of that oil plume from the Deepwater Horizon spill in the Gulf of Mexico in April, the oil that either was or wasn't continuing to plague the Gulf, are not in conflict after all.

Turns out that all the reports were more or less right. Yes, the vast oil plume, a mile wide and nearly a mile deep, was there in May and June, just as groups of scientists from the Lawrence Berkeley Lab and the Woods Hole Oceanographic Institution said it was. But most of the plume was gone by early this month — ahem, just as the government said it was.

(Sound of frantic backpedaling by the present writer, who last week accused the gov't of Orwellian doublespeak on this topic and who this week extends apologies and issues a correction.)

The reason the plume is vanishing is evolution in action. The reason the plume is vanishing is oil-eating bacteria, including never-before-seen species specially adapted to deal with events like the oil spill and its enormous oil plume. These creatures were discovered by the Berkeley team, which looked for microbes and microbial products and found lots, publishing their second study this week. They estimate that the microbes can degrade half a given quantity of oil in about three days. (The Woods Hole folks had estimated microbial activity indirectly by measuring oxygen, concluding that the bugs weren't doing much.)

You will find a particularly helpful explanation not in a blog, but in a newspaper news story, thus demonstrating that the MSM aren't quite dead yet. David Brown writes in the Washington Post:

From a purely Darwinian point of view, this was no surprise. About 500,000 barrels of oil get into into the gulf's water each years through seafloor seeps. (In comparison, the 1989 Exxon Valdez spill in Alaska was 260,000 barrels.) Natural selection has favored microbial species able to quickly use oil as a nutrient when it is around. It's particularly favored ones that can use it in very cold, bottom waters — conditions generally not conducive to rapid bacterial growth. Many of the species flourishing in the samples taken by the Berkeley group actually consume oil better at 40 degrees Fahrenheit than at 70 degrees.

Lots of bloggery, too, naturally. The Knight Science Journalism Trackers were on the case; see Phil Hilts here, Boyce Rensberger here, and obtain further elucidation from the several comments to both posts. At the Columbia Journalism Review's blog The Observatory, Curtis Brainard also chronicles journalists' perplexity.

At Deep-Sea News, Dr M ruminates on the microbes and the effects of oxygen (or lack of it) in the depths. At Wired Science, Brandon Keim is cautiously optimistic, with the emphasis on cautiously. Greenwire's Katie Howell reports how the administration is not backing down from its earlier estimates that some 75% of the oil is gone. (Once more, apologies, but I imagine the Berkeley paper is helping to stiffen official backbones.) Robert Service is at the American Chemical Society meeting in Boston and reports for ScienceInsider that the news about environmental damage from the spill appears encouraging.

MIT LAUNCHES CAMPAIGN TO STARVE ANIMALS. So it turns out that MIT is aiming to put those marvelous helpful bugs out of business — to say nothing of out-of-work Gulf fisherpersons who were bringing in some income by assisting with the cleanup. MIT engineers are working on solar-powered robots called Seaswarm. Rosa Golijan at Gizmodo reports that they claim a 5000 robot-strong Seaswarm could have cleaned up the Gulf spill in a month.

But MIT, what will the bacteria eat? What will the unemployed fisherpersons eat?

THE EVOLUTION OF SCIENCE BLOGGING INFRASTRUCTURE. Running out of time, as usual. But not before calling your attention to a major new science blogging development.

Scienceblogging.org is something we have needed for a long time: a science blog aggregator. The slogan is "Your one-stop shop for the most recent science blogging." Links to hundreds of science blog posts, maybe thousands, including several in languages other than English. They are making a huge effort to be comprehensive, and as far as I can tell achieving it.

Aug. 26, 2010

Drexel University online