Round tubs teem with live fish for sale since carp is the traditional centerpiece of the Christmas feast in much of central Europe. Oddly enough, when contained in these round tubs, the carp tend to align themselves with an invisible north-south line. One might assume this is because the fish are seeking Santa in his North Pole home, but scientists argue the behavior is the result of a previously unknown capacity to perceive geomagnetic fields.
This detection of the Earth’s magnetic poles is a well-studied phenomenon in birds and other migratory species. These animals travel long distances north and south every year based on a compass that scientists typically explain with the pull of the planet’s magnetic poles.
But no one had thought to explore this phenomenon in carp until the researchers noticed the curious behavior of fish at the market. The large numbers of carp in their pre-Christmas tubs provided a perfect set-up for a larger scientific analysis, which looked at over 14,000 carp from 25 different markets around the Czech Republic. The researchers found that factors such as light, noise, and onlookers didn’t seem to have an effect on the carp’s orientation—regardless of those, the fish tended to line up as if on cue. Geomagnetism was the most likely force, they concluded, and this is the first time such a response has been recorded in carp.
Images courtesy of visivastudio via Shutterstock (left) and Vlastimil Hart et al. (right).
Here’s the latest lesson from the ant world: kidnapped babysitters may not be the most reliable. Evolutionary myrmecologist Susanne Foitzik studies a species of ants that, instead of using its own workers to raise its young, kidnaps larvae from another species and puts them to work as babysitters. But, she’s found, the free labor has a price.
The folks at Backyard Brains, a DIY-neurobiology project, made these pigment-producing cells in a dead squid pulse to the base beats of Cypress Hill’s “Insane in the Brain.” Go watch that thing right now.
Done? Wowed? Prepare to be more wowed: They did it by exploiting the fact that electrical current is key to both the actions of cells and the playing of mp3s. These pigmented cells, called chromatophores, are surrounded by muscle cells, and it’s by flexing these muscles that the squid reveals its colorful spots. By hooked up the nerve that sends the flexing orders to the wire of a set of earbuds, they got these amazing results.
Phallostethus cuulong was swimming quietly in Vietnam’s Mekong River, minding its own business, when humans discovered the fish in 2009. And now that researchers have described P. cuulong [pdf], we can’t help violating its privacy by gazing unabashed at its most interesting feature. That feature sits on the throat in the form of a priapium, an organ with as many parts as a Swiss Army knife, most of which contribute to a single function: making as many babies as possible.
My sister, a medical student who has worked in a pathology lab, recently mentioned in passing that specific strains of bacteria, grown in an incubator, can have some pretty unusual smells. When I asked what she meant, she drew me this table (on some handy Discover stationary).
Now, I’ve grown plenty of yeast in my day, and they just smell like gym socks. Maybe, if you get some wild ones in there, like gym shorts (I’ve never enjoyed fancy beer made with wild yeast. Too redolent of crotch).
This level of olfactory whimsy, then, was totally new to me: Pseudomonas aeruginosa smells like flowers? Streptococcus milleri smells of browned butter? Clostridium difficule, scourge of elderly intestines, bringer of fecal transplants, smells like horse poo? I’ll confess, I never quite thought about what happens when you get millions of a single kind of bacteria all together in one place and take a nice long sniff. I did not think it would ever be pleasant. I was wrong.
Robots like this? That’s nuts.
If mechanical engineer David Hu ruled the world, it would be crawling with robots based on mosquitoes, snakes, and Mexican jumping beans. Hu’s lab studies animal locomotion, but the research goes beyond the traditional slow-motion footage of creatures running. Instead, Hu examines topics like how water striders and rafts of ants stay afloat on water’s surface, the mechanics of giant pumpkins collapsing into amorphous blobs under their own weight, how snakes’ scales affect their slither, the optimal way for furry animals to shake off water, and how mosquitoes survive collisions with comparatively huge raindrops. His group has even analyzed the motion of Mexican jumping beans, which is due not to some inherent magic in the “beans,” but rather to temperature-sensing moth larvae in hollow seeds. (When the ground heats up, the larvae sense the change in temperature and make their seedy houses twitch into rolling movements towards cooler, shadier ground.) These topics are weird and interesting enough to have garnered Hu’s work plenty of media coverage. But when it comes to earning funding, “weird and interesting” doesn’t always cut it. What’s the practical purpose of this research? Instead of shrugging and saying, “Now we know how mosquitoes struggle out from water droplets 50 times their size! That’s pretty cool!” Hu has come up with a standard one-size-fits-all application. At the end of his papers, he adds that whatever wacky phenomenon he studied could inspire…robots! Read More
If these fossilized turtles had a final thought, it was probably, “If you’ve gotta go, go out with a bang!” New evidence suggests that the ancient reptiles died while mating and were preserved in their final embrace.
Germany’s Messel Pit Fossil Site contains black oil shale that has preserved even the soft tissues of tens of thousands of 47-million-year-old fossils. Among them, the only ones found in pairs were nine sets of coupled carettochelyid turtles, and although previous research speculated that the reptiles were copulating, there was no proof until now. German researchers discovered that the turtles were all in male-female pairs (in the above image, the larger fossil on the left is the female), and that their tails were aligned, a position that indicates the close contact of a mating stance.
Adélie penguin chicks chase an adult.
Penguins are undeniably adorable. What other animal waddles around in a little tuxedo? But don’t let that cute exterior fool you: on a 1910–1913 Antarctic expedition, surgeon and zoologist George Levick bore witness to some surprising sexual behaviors of Adélie penguins, including coerced sex and necrophilia. In fact, the paper he wrote on the penguins’ sexual habits was considered too explicit to be published during the Edwardian era, and has only recently been rediscovered after spending almost a century hidden away in the Natural History Museum at Tring.
Levick travelled to Antarctica with Captain Robert Scott’s 1910 Terra Nova expedition, where he spent 12 weeks in the world’s largest Adélie penguin colony at Cape Adare, observing the birds, taking photographs, and even collecting nine penguin skins. After his return, Levick used his daily zoological notes as source material for two published penguin studies, one for the general public and a more scientific one to be included in the expedition’s official report. Intriguingly, this second account includes vague references to “’hooligan’ cocks” preying on chicks. Levick merely writes, “The crimes which they commit are such as to find no place in this book, but it is interesting indeed to note that, when nature intends them to find employment, these birds, like men, degenerate in idleness.”
Now, modern-day researchers have discovered that Levick did in fact describe the hooligans’ crimes in the paper, “The sexual habits of the Adélie penguin.” This paper was expunged from his official account, probably because it was too disturbing for Edwardian mores. Levick himself covered some explicit passages of his personal notes with coded versions, rewritten in the Greek alphabet and pasted over the original entries. Although the paper was withheld from the official record, researchers at the Natural History Museum did preserve it in pamphlet form, printing 100 copies labeled, “Not for Publication.” But most of the originals have been lost or destroyed, and no later works on Adélie penguins cited this paper until recently, when researchers in the Bird Group at the National History Museum at Tring discovered one of the original pamphlets in their reprints section.
An album of songs inspired by animals doesn’t sound immediately promising. It brings to mind certain cassette tapes from my youth, featuring bearded men singing earnest ballads about the banana slug (not a joke; I actually had that tape).
But Songs for Unusual Creatures, by composer Michael Hearst, is a beast of a different color. If you popped it into your player without any context at all, you’d hear a catchy, rhythmic cross between classical music and jazz, threaded with eerie theremin solos and digeridoo bass lines. It’s the kind of music you might play on endless loop while you study, work out, or write (ahem). Lots of syncopation and kooky instruments, as well as clear melodies, keep the sonic landscape interesting. (You can see Hearst perform one of the songs above.)
But it’s not just pretty sounds. Each track on the CD draws its inspiration from one of 15 unusual creatures, the kind of evolution-honed weirdoes that readers of this blog and science writers like myself enjoy so much, like the blue-footed booby, the Chinese giant salamander, the honey badger, and the humpback anglerfish. Each of these animals is profoundly odd—the tardigrade (track 11), for example, is one of the few creatures that can survive the vacuum of space—and their eponymous songs are also distinctively strange. “Dugong,” about the cigar-shaped, seagrass-grazing marine mammals, is a spacey, blue little tune. “Tardigrade” sounds like the love child of a Gypsy circus band and a jazz quartet.
Don’t mess with this.
Folks, those turtle-shaped sandboxes are not just a consumerist fantasy: Carbonemys cofrinii is an extinct turtle with a 10-inch skull and, more impressively, a shell that rounds out to five feet, seven inches in length. That really is big enough to dig around in. That’s also the same height as the grad student who found the 60-million-year-old fossil in a Colombian mine.
The turtle was so big that it probably drove off other turtle competitors and dominated the lake by itself, scientists say. They think that C. cofrinni preyed on mollusks and small reptiles, like the one depicted in this artist’s interpretation. If we’re going to be spending time in the belly of a turtle, though, we’d personally prefer it to be full of sand and toys rather than chewed up food.