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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)

Filed under “Hang on a sec”: a new scientific paper has called into question one of the most exciting paleontological finds of the 21st century. Soft tissue discovered deep inside a Tyrannosaurus rex legbone may be a recent “biofilm” (what you might call scunge if you found it on a dishrag), not remnants of the Toothy One after all. That’s the suggestion of a team led by Thomas Kaye, writing in the scientific journal PLOS One.

Avid Smithsoniacs and dino fans may remember bits and pieces of this story. In 2005, paleontologists Mary Schweitzer and Jack Horner were stuffing a T. rex femur inside a too-small helicopter on their way home. They cracked the bone in half to make it fit, and Schweitzer noticed a goopy residue on the 65-million-year-old insides of the bone (see the Smithsonian story). Then this April, Schweitzer and her colleagues isolated a protein called collagen from the sample, analyzed it, and found striking similarities to the collagen of modern birds.

Kaye’s contradictory opinion comes from using an electron microscope to peer at similar residues he found in different fossils. Studying fossils of 17 dinosaur and mammal species, Kaye and his team saw evidence of biofilms, or slime left behind by bacteria that grew on the bone long after the dinosaur’s death.

Where Schweitzer’s group described the remains of red blood cells, Kaye’s team thought they were seeing iron-rich structures routinely built by bacteria. (The iron content and the structures’ characteristic shape might have made them look like red blood cells in some analyses, Kaye suggested.) Kaye found these structures time and again in his samples - even in a fossilized shell, which never would have contained blood at all. Worst of all, carbon dating suggested the biofilm was as recent as 1960.

Of course, there’s still the matter of the collagen’s similarity to chickens and ostriches - a detail Schweitzer was quick to point out to reporters. And Kaye didn’t sample the T. rex in question, leaving open the chance that Schweitzer’s find was the genuine article.

Personally, I’m leaning toward believing in the extraordinary. At least until the collagen results are explained (I mean, can anyone tell me if bacteria even make collagen?) Either way, it’s fascinating to listen to the well-constructed arguments on both sides. That’s what science is all about.

It’s been a good week for people who look through microscopes at fossils. First off, Scientific American told us about some German scientists who discovered evidence of 400-million-year-old life trapped in seawater trapped inside volcanic rock.

Far more buzz circled around the second report: that we may be able to figure out what color dinosaurs and ancient birds were. This means that one day, paleontologist-artists may have to stop dreaming up rosy purples and outlandish greens to clothe their dinosaurs in (remember Mark Witton’s lovely pterosaurs a few posts ago?).

Is there any ephemeral detail that scientists can’t discover about long-dead creatures through clever chemistry? They’ve figured out the diet of an extinct seabird, learned about Aztec travels from records in exhumed teeth, and now they’ve put back together the stripes on a 100-million-year-old bird.

The evidence sat in front of them for years in the form of a powdery residue on some fossils. It was long thought to be the meaningless remains of carrion-eating bacteria, but Yale graduate student Jakob Vinther’s electron microscope revealed the powder looked exactly like the pigment-bearing sacs that occur on modern-day feathers. Nowadays, those sacs are full of melanin which give birds colors ranging from black to russet brown.

Though the work was done on fossil birds, the scientists report that similar residues from dinosaur scales and the hair of ancient mammals may reveal their colors as well. The researchers were also careful to point out that the residues didn’t contain any intact melanin (unlike the T. rex discovered in 2005 with actual protein still preserved inside a massive thigh). A hundred million years is a long time, after all.

(Image: J. Vinther/Yale)

It’s called astrobiology: the idea that life emerged somewhere in the cold reaches of space, and only made it to Earth belatedly, after stowing away on a meteorite or comet. It sounds far-fetched, but astronomers have a growing body of evidence that supports the idea. They added another piece this week, in the journal Earth and Planetary Science Letters.***

And after all, say the astrobiologists, life had to originate somewhere. Reassuringly, their leading proposals involve scenarios considerably more humble than standard Hollywood images of luminous humanoids arriving in gleaming steel cylinders.

In this week’s finding, scientists isolated from an Australian meteorite two molecules called uracil and xanthine, each of which consists of 12-15 atoms of carbon, oxygen, nitrogen, and hydrogen.  (The carbon in the samples differed in makeup from what’s found on Earth, indicating the find wasn’t the result of contamination once the meteorite landed.)

The find suggests that somewhere out in space conditions are right for such complicated molecules to form spontaneously. Even more exciting, uracil and xanthine are precursors of two pivotal molecules in living organisms, RNA and DNA. The way astrobiologists interpret this, life may not have zapped into existence in a single, unique flash in some earthbound primordial soup after all (which was the way I learned it in school).

Rather, the building blocks may form, en masse, in cold interstellar factories, and then perhaps travel the cosmos on the backs of comets, waiting for a crash landing. Like little starter kits.

(Image: Bill Saxton, National Radio Astronomy Observatory/National Science Foundation)

***Fascinated (or skeptical)? Read about some more pieces of evidence here, here, or in the captioned version of the above picture, here.