Archaeoentomology is a strange little corner of archaeology. Its practitioners search for signs of ancient bug life—fossilized eggs, old fly pupae, the like—in dig sites to tell, for instance, whether a body lay exposed before burial. One area they’d really like to know more about is what moves into coffins with bodies once they’ve, ah, started to go to earth. The worms crawl in, the worms crawl out, the worms play pinochle on your snout, to be sure, but which worms?
After three and a half years of mucking around Florida cow pastures, veterinary entomologist Philip Kaufman has collected 62,320 dung beetles. That comes to about 60 beetles a day, if you’re counting. What’s the secret to his beetle-catching success? The New York Times Green Blog has got the scooper—erh, scoop:
He collected fresh dung with an ice cream scooper, then packed it into small pouches that he froze in his lab. He set up pit fall traps, or mesh-covered funnels partly buried underground that were baited with the thawed dung balls. Positioned at a slant, the mesh encouraged beetles to fall into a bit of PVC pipe from which they could not escape. After placing the traps, he would return within 24 hours to investigate the day’s catch.
Squatting around cowpats paid off: Kaufman’s research on the diversity dung beetles has just been published in the Annals of the Entomological Society of America. He isn’t the only one with an affinity for dung beetles though. The little critters actually do a lot of a farm’s clean-up work, eating through the dung that can quickly pile up when a single cow produces 82 lbs of manure a day. Cow farmers have been asking Kaufman for dung beetles to stock their farms.
Read more about the fascinating world of dung beetles at the Times.
Image via Flickr / mbarrison
If you have been itching to clamber across glass windows or cling to a ceiling like Spiderman, that wacky dream may today be one step less wacky than it was yesterday. Researchers Paul Steen and Michael Vogel of Cornell University think they can help you tap into your inner Spidey through a palm-sized adhesive device that could one day allow people scale walls.
The scientists didn’t work with any real-life arachnids while designing their tech, instead drawing inspiration from a beetle species in Florida that can stick and unstick from leaves at will. The leaf beetles can withstand pulling forces of 60 times its own body weight by using the surface tension of many tiny drops of water, which form “liquid bridges” between the beetle’s body and the leaf.
The scientists’ contraption looks like a little plate and could be worn either on the palm or as a boot sole. While the device isn’t strong enough to be tested on people yet, it did keep this Lego man dangling from a slick glass shelf.
Trigona carbonaria is a bee without a stinger, one of the 10 or so out of 2,000 Australian bee species to lack the feature. This doesn’t appear to have been any concern… at least not until the hive beetle Aethina tumida showed up. This invasive insect may have reached the island continent along with a flock of athletes during the 2000 Olympic Games in Sydney, and as the name suggests, it like to invade beehives. But it hasn’t been very successful in this case, thanks to creative defensive tactics by the bees.
Since the worker can’t sting, they instead make the beetles into mummies. Workers swarm to the approaching beetle, which adopts the turtle defense–tucking in its head and legs, according to researcher Mark Greco, whose team used CT scans to see the action inside the hive. Then the construction onslaught starts. From BBC News:
After [a female] lays her eggs, she seals each one in a bell-shaped case. When the larva hatches, it performs some renovations, cutting a hole in the roof and enlarge the structure with their own poo. By sticking its head and legs out, it converts its excremental maisonette into a mobile home, one that it carries around with them until adulthood.
This beetle behavior has been well established by scientists. However, the leaf beetle Neochlamisus platanithey has been singled out by researchers for its “elaborate example of faecal architecture.” The larvae add a little insulation in the form of plant hairs, called trichomes, which help ward off predators, according to new research.
Staged attacks on larvae with and without fecal shelters demonstrated that poop-protected larva were less likely to be attacked by crickets, spined soldier bugs, and green lynx spiders than unprotected larva. NERS explains why:
Even if a predator investigates the case, they must first breach the unappetising shield, and the larva doesn’t make it easy for them. [The researchers] saw that, in some cases, the larvae pulled their cases down flush with the floor, making them even harder to penetrate. That defence was particularly effective against the bugs, whose stabbing mouthparts couldn’t break through the wall of the case. Some of the larvae also wiggled their cases back and forth, which could serve to shake off or startle a predator.
Even if a predator breaks through the case (as frequent holes in the structures suggest), they’d meet a large concentration of trichomes in the attic before they reached the larva underneath.
For beetles at least, putting up with their mothers’ crap can save their lives.
Discoblog: Enough of This S#%t! Dung Beetles Morph into Millipede-Eaters
Discoblog: Finally! An iPhone App That Lets You Track Your Bathroom Habits
Discoblog: Archeologists Find the Darnedest Things Digging Around in Hyena Poop
Image: Wikimedia Commons / Neochlamisus
It’s hard to get any respect when you eat feces. Maybe that’s why one species of lowly dung beetle has forsaken its namesake for a more glamorous place on the food chain—that of a ferocious carnivore. The species Deltochilum valgum may look like any other dung-roller, but it has adapted to feed on giant millipedes more than ten times its size—for comparison, picture a house cat taking down and subsequently devouring an anaconda.
When rumors of Peruvian dung beetles eating millipedes started floating around, a research team led by Trond Larsen of Princeton University headed to the Peruvian rainforests to see for themselves. After setting up more than 1,000 beetle traps baited with either dung, fungus, fruit, or millipedes in various stages of life and death, they found that D. valgum‘s food of choice is in fact injured millipedes. When D. valgum finds an injured millipede, it uses its powerful hind legs—originally adapted for rolling neat balls of dung—to grasp the millipede’s body. After the millipede finishes flailing about, the beetles uses its sharp teeth to saw between its prey’s body segments, sometimes decapitating it. The corpse is then dragged to a safe location where the beetle devours the soft inner tissue.