In the Tangled Bank, I wrote about how life has to evolve within constraints–constraints of physics, development, and history. One of the examples I used was the laryngeal nerve in giraffes. It travels down the giraffe’s neck, takes a U turn, and then heads back up again. It seems ridiculous, but makes sense if you think about how it was laid down in fish without necks, and was then gradually modified–rather than re-engineered outright–as tetrapods grew necks, and then taken to surreal extremes in the long-necked giraffe.

Youtube has an excellent snippet of Richard Dawkins hanging out with an anatomist as she dissects a giraffe’s neck, to show what this remarkable evolutionary legacy really looks like. Warning: it’s bloody, like all dissections. But it’s worth the gore!

(PS: Anybody know what show this came from?)

(PPS: Turns out, it’s from “Inside Nature’s Giants.” Wish I could see it from the States!)

Originally published August 30, 2010. Copyright 2010 Carl Zimmer.

On Wednesday, EO Wilson and colleagues at Harvard came out swinging at a major concept in modern evolutionary biology, known as inclusive fitness. A generation of scientists has used it to explain how animals help each other–because they’re kin. In the new paper, Wilson and colleagues say it’s superfluous.

I’ve written a story about the paper–and the sparks flying from it in biology circles–for tomorrow’s issue of the New York Times. I very much liked the way Jim Hunt, an expert on wasps, described the debate to me:

“Things are just bouncing around right now like a box full of Ping-Pong balls.”

To see what he means, check out the story.

[Image from Alex Wild]

Originally published August 30, 2010. Copyright 2010 Carl Zimmer.

The New York Times, August 30, 2010

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Why are worker ants sterile? Why do birds sometimes help their parents raise more chicks, instead of having chicks of their own? Why do bacteria explode with toxins to kill rival colonies? In 1964, the British biologist William Hamilton published a landmark paper to answer these kinds of questions. Sometimes, he argued, helping your relatives can spread your genes faster than having children of your own.

For the past 46 years, biologists have used Dr. Hamilton’s theory to make sense of how animal societies evolve. They’ve even applied it to the evolution of our own species. But in the latest issue of the journal Nature, a team of prominent evolutionary biologists at Harvard try to demolish the theory.

Continue reading “Scientists Square Off on Evolutionary Value of Helping Relatives”

I’ve contributed my first article to Technology Review–a short profile of Tim Lu of MIT, one of TR’s 35 innovators under 35. Lu is engineering viruses to attack biofilms–not just the ones that make us sick, but the ones that gum up factories and HVAC systems. Elegant and practical at the same time. Congratulations to all the winners!

Originally published August 27, 2010. Copyright 2010 Carl Zimmer.

Conservation Magazine, August 27, 2010

Link

Win-win solutions can be hard to come by. But if Cornell University soil scientist Johannes Lehmann is right, there may be a way to lower our emission of heat-trapping greenhouse gases, save millions of people’s lives, and significantly boost the productivity of the world’s farms—all at the same time. And, most remarkably, his strategy is based on a deceptively simple technology invented 8,000 years ago.

Lehmann’s idea starts with organic leftovers that people normally burn or leave to rot—forest brush, corn husks, nutshells, and even chicken manure. When this stuff decays or goes up in smoke, it releases vast amounts of heat-trapping carbon into the atmosphere.

Continue reading “Black is the New Green”