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Check out this deft rap about life on other planets by Jonathan Chase, a.k.a. Oort Kuiper (yes, that Oort and that Kuiper). The delivery is subdued and literate, like Massive Attack-era Tricky, and the video incorporates clips from Cosmos, the classic PBS series narrated by Carl Sagan. Bonus points for cribbing footage from SETI and working in a cameo by Gregor Mendel.

The bar on science rap has been raised. Once a novelty act confined to late-night grad-school potlucks, where just finding something to rhyme with “plate tectonics” was a triumph; now you get spot-on lyrics backed by leaping basslines and 1950s samples.

Other recent triumphs of the genre include the cogent Large Hadron Rap (405,000 hits in less than a month) and the salt-soaked Cruise, Cruise Baby. Say what you want about the LHR’s backup dancers (I was under the impression that experimental physics required nanosecond-accurate timing) - but I learned more about the setup, mechanics, and ambition of the Large Hadron Collider from this rap than from everything I’ve read on the subject previously put together.

Hat tip: Knight Science Journalism Tracker [though Tracker, please note that's a British accent]

I spent last week at the International Society for Behavioral Ecology meetings at Cornell University.

Behavioral ecology, the study of what animals do and how it affects their lives, can be delightfully arcane. One research team designed a robot stickleback in order to learn how many fish it takes to persuade a school to change direction. (Early results suggest the answer is two.)

Another team found that African honeybee workers surreptitiously raise their own eggs rather than those of their queen overlords, in effect staging a bloodless coup.

Mitchell Baker, of Queens College, New York, had some amazing insights into pesticide resistance studying the formidable Colorado potato beetle. “If you leave them alone,” he said, “they will eat a field down to brown sticks.”

A pesticide, like an antibiotic, is supposed to kill any pest that’s not resistant to it. But when survivors get together to breed, one thing they all have to bequeath to their young is pesticide resistance. “Potato beetles can evolve resistance to anything you can throw at them, usually within three generations,” Baker said.

Resistance can have a downside for the beetle, though. It comes with a grab bag of handicaps. Through novel experiments at agricultural fields, Baker discovered that pesticide-resistant beetles hatch later, move more slowly, have compromised immune systems, mate less successfully, raise fewer young, die off during the winter at greater rates, and get cannibalized by their nestmates more often than non-resistant beetles.

Apparently, the genes that make a beetle resistant have such debilitating side-effects that it takes the application of deadly pesticides just for them to survive the competition. Baker’s research could point to ways to postpone widespread resistance by taking advantage of those weaknesses.

It’s tempting to view the world as a collection of species perfectly adapted to living together. But what I find fascinating about evolution are the compromises that constantly play out on any species’ scrap heap of talents. For potato beetles, pesticides are pulling resistance to the top of the pile. But change what’s killing them-a different pesticide, perhaps, or maybe hotter summers-and resistance will fall to the wayside in favor of something equally vital for the moment.

(Image: Colorado potato beetle; Scott Bauer/USDA/Wikipedia)

Don’t worry, that’s not a giant bug on the first tomato of summer. It’s a tiny bug on a chile pepper about the size of a caper. But don’t let its size fool you: that’s one of the hottest peppers out there, the chile piquin, which grows wild in Bolivia.

I remember sampling a few of these chiles at a dinner party in Missoula, Montana, some years ago. Scientists describe the taste as “pungent,” which is kind of like calling a bad pinot noir “cheeky” or Henry VIII “irritable.” My recollection goes more like this: a whiff of ozone, a grass fire ripping across my tongue, and then the lingering sensation of pavement that has just been peeled out on by a 17-year-old in his parents’ car.

This week, the host of that party - Joshua Tewksbury, now an assistant professor at the University of Washington - announced a breakthrough in understanding why chiles get so hot. Turns out it has little to do with punishing the taste buds of mammals; nor science’s next best guess, which involved singling out birds to carry the seeds to useful places.

Instead, the chemical warfare seems to be directed at a fungus, called Fusarium, that’s deadly to chile seeds. Spores get into the chiles through holes made by bugs as they feed. (Look closely, and you can see this bug’s straw-like beak plunged between its two front legs and into the chile’s skin.)

Like good scientists, Tewksbury and his research team went to great lengths to test their idea. They sampled wild chiles across 600 square miles of Bolivia. Chiles with more bug-beak holes contained more the spicy chemical capsaicin - and were infected with fungus less often. To clinch the deal, the researchers built imitation chiles and loaded them with differing amounts of capsaicin. Like the real thing, hot fakes were much more resistant to fungal infection.

So chile plants turn up the heat depending on the risk they face from fungi. Could something similar be at work in the evolution of culinary marvels like the four-star panang curry I had for lunch? Did humans start eating fiery foods, back in the days before refrigeration, as a kind of insurance?

(Image: University of Washington)

This week I’m blogging from a meeting of 1,000 ornithologists in Portland, Oregon.

At a symposium entitled “Avian CSI” I heard about sophisticated ways that biologists learn intimate details about birds from tiny pieces of recovered evidence. A team of Smithsonian scientists is especially good at identifying bird remains - even mere specks exhumed from the guts of a giant snake.

It turns out that Everglades National Park has a growing demand for experts in snake-meal identification. Wild Burmese pythons, most likely released by fed-up pet owners, have graduated from amusing 10-o’clock-news material into a growing, self-sustaining, and hungry population. Park officials have now captured and killed more than 600 of the snakes. Some contained a full complement of eggs ready for laying.

A host of remarkable birds call the Everglades home, including stunners like the roseate spoonbill, scarlet ibis, reddish egret, and the endangered wood stork and threatened limpkin. And necropsies of captured pythons have turned up plenty of feathers covered in fragrant python digestive slurry. But park officials had no idea which birds they came from. So they turned to Carla Dove and the “feather lab” at the National Museum of Natural History.

To clinch her IDs, Dove uses deceptively low-tech methods that hinge on experience and close observation. There are so many sources of DNA in a python’s stomach that genetic analyses are complicated. Instead, Dove painstakingly cleans feathers and bones, using a fume hood to suck out the most offensive of the smells. Sometimes, she said, she runs down the hall to dry her feathers with the hand dryer in the women’s bathroom.

She puts cleaned feathers under a microscope to analyze their microscopic structure, which differs reliably among different groups of birds. (Here, the distinctive barbules of a common backyard mourning dove.) Dove uses traditional light microscopes instead of electron microscopes because she needs to see into the sample, not just the surface. The final step is to compare python meals with the reference specimens in the Museum’s enormous collection.

So far, the team has identified some 29 species from the bowels of Everglades pythons. Victims include everything from the meatball-sized house wren to the 4-foot tall great blue heron. Rails, coots, and gallinules - slender birds of the marshes - are most frequently eaten, but at least one limpkin and one wood stork have vanished down python throats. One meal even included a magnificent frigatebird, a tropical seabird with a seven-foot wingspan whose closest roosting site is 10 miles away.

The work is fascinating, but Dove says she hopes people think twice before releasing the python they’ve grown tired of into the Everglades. Even so, she says, the population may already be too well established to bring back under control. But the work does point out the way museum collections can yield unexpected dividends.

“A hundred and fifty years ago, when people started this collection,” Dove said, “They could not have imagined the uses we would put these specimens to” - including identifying birds involved in airplane strikes as well as ancient DNA studies. “But they’re crucial to the work we do today. It’s a reminder that we need to continue these collections for purposes we may not have dreamed of yet.”

(Image: Burmese python by Roy Wood, National Park Service; mourning dove feather courtesy Carla Dove)

Diamonds are the subject of one of the great battles between the forces of Marketing and the forces of Matter. In one corner is DeBeers, with the best advertising slogan of the 20th Century, “Diamonds are Forever.” In the other corner are the chemists, with the knowledge, since 1796, that Diamonds are Carbon.

H. Tracy Hall was the first guy to turn carbon into diamonds. He died last week at age 88.

The L.A. Times has the best obituary of Hall that I’ve seen. I got a kick out of all the tinkering he had to do before he hit on the right contraption for cooking up diamonds:

“Hall had built a pressure chamber that he called the “half-belt” that had been used to create high pressures in a 35-year-old Watson-Stillman press that leaked so much water from its hydraulics that he had to wear rubber boots while working with it.”

On December 16, 1954, he succeeded:

“My hands began to tremble; my heart beat rapidly; my knees weakened and no longer gave support. My eyes had caught the flashing light from dozens of tiny . . . crystals.”

Fifty years later, it’s still a thrill to create a diamond, a thrill we tried to capture in a story in the June issue of Smithsonian magazine.

One of the barriers to publishing a story about diamond growers is that almost everyone involved is touchy about secrecy. Private companies want to protect their supersecret recipes–some combination of temperature, pressure and vaporized carbon–from competitors, and nobody knows how far the natural diamond powers will go to protect their market.

Hall had his share of secrecy worries as well. He had been working for General Electric, but they didn’t support his early diamond experiments and gave him a measly $10 savings bond when he succeeded:

“Disheartened by the lack of credit, he began looking for another job, landing at Brigham Young University in Provo, where he planned to do high-pressure research. But the federal government had slapped a secret label on the apparatus, which effectively prevented Hall from using it.

“His solution was to invent another apparatus, called the tetrahedral press, that was even better and that circumvented all the patents held by GE. He published his research in a widely read journal, but shortly thereafter, the government slapped a secret label on that device as well.”

The official “shush” didn’t last long, though, and Hall started his own company and kept making diamonds.

His successors have started selling gem-quality diamonds in the past few years, and the natural diamond industry has responded by claiming that their diamonds are different.* As a DeBeers spokesperson told our author: “When people want to celebrate a unique relationship they want a unique diamond, not a three-day-old factory-made stone.”

But H. Tracy Hall knew, with the clarity of a chemist, that diamonds are diamonds, and diamonds are carbon.

*For more on diamond marketing, see this fun critique of the cult of the diamond engagement ring

–Laura Helmuth