Hard to believe—they’re insects, not astronomers, for goodness sakes! As Discover mentions, the dung-dining coleopteran are in good company, navigation-wise:

Christopher Columbus traveled by following the stars, as did Harriet Tubman.

Some of the same Swedish researchers who tested dung beetles’ sense of direction and published last year, have now found that these brilliant beetles dabble in celestial navigation of a sort.

Publishing last week in Current Biology, the researchers tested one species of dung beetle, Scarabaeus satyrus, in a planetarium in Johannesberg. They found that the beetles used the entire Milky Way to guide their dung in a straight line to their destination. As Ed Yong notes in National Geographic:

If they left out this galactic stripe, or only added the 18 brightest stars, the beetles took much longer to find their way out.

The researchers were thorough, too. In their experiments, they gave the beetles caps to block the light from reaching their eyes. Once again, the beetles wandered from the most direct route.

The scientists believe that although the beetles’ eyes are too weak to distinguish individual constellations, they use the gradient of light to dark provided by the Milky Way to ensure they keep rolling their balls in a straight line and don’t circle back to competitors at the dung pile. The New Yorker offers a particularly charming description of the experiment.

Not sure, even with a ball of poop, I could navigate as well as dung beetles—day or night!

Image: Maria Dacke

A leggy neighbor

The leggiest animal on the planet lives just south of San Francisco, according to a new report in ZooKeys. Illacme plenipes comes the closest to the description of a millipede than any of its relatives—females have as many as 750 legs!

Even millipede researcher Paul Marek thinks Illacme plenipes is special. Its plentiful legs have claws and National Geographic News lists more of its cool features:

…massive antennae (relative to the scale of its body), which the millipede uses to feel its way through the dark; a jagged and translucent exoskeleton; and body hairs that produce a sort of silk that may help Illacme plenipes adhere to the undersides of boulders. And unlike in other millipedes, the mouth of this species is specifically structured for piercing and sucking plant tissues.

Wanna get to know your neighbor? Movies and images are available for download here.

Insect hearing aids

A recent publication in Science explores how certain rainforest katydids are able to listen like mammals do, but much more efficiently. Katydids’ hearing organs are near the insects’ knees, and much like human ears, gather sounds from the air and transmit them to the brain in fluids.

For humans and other mammals, sounds are collected by the eardrums in vibrations, which are transferred by three ear bones to the cochlea. Fluid in the cochlea translates these sounds and sends them to the brain.

In katydids, the ear bones are missing, simplifying the process. (An excellent comparison illustration is available at Scientific American.) This simplification could lead to better hearing aids for humans, according to the lead author of the study, Fernando Montealegre-Z. “These findings change our views on insect hearing and open the way for designing ultrasensitive bio-inspired sensors.”

Insect-inspired water bottles

Finally, recent news reports describe a new company creating water-collecting bottles for “the most arid regions of the world.” Their inspiration? The Namib Desert beetle. Wired UK describes the insects’ process of water collection:

The beetle survives by collecting condensation from the ocean breeze on the hardened shell of its wings… The beetle extends and aims the wings at incoming sea breezes to catch humid air; tiny droplets 15 to 20 microns in diameter eventually accumulate on its back and run straight down towards its mouth.

Want more exciting entomology?

How about disease-fighting ladybirds? Learn more at ScienceShot. Insect movie stars? Watch their cameos at the New York Times.

Katydid image: Fernando Montealegre-Z and Daniel Robert

So when I heard he just returned from Alaska, it didn’t surprise me.  But his description of the area he studied did:  “painfully lush.”

His beetles are flightless, “long-legged runners” and like rocks and snow. But Dave went to a valley in the Juneau Icefield that was a green oasis—full of vegetation including blueberries and heather and hemlocks, willows and alders.

Eighteen years ago, Dave described a species of beetle from nearby Glacier Bay—about 34 miles south of his destination this summer. He wanted to see if he could find those beetles again or unearth a similar species.

His son is the director of the Juneau Icefield Research Program, or JIRP, which offers undergraduates an exciting summer of scientific study and fieldwork in glaciology, geology, botany and more. The students get to work side-by-side scientists in the different fields—in addition to Dave, this trip included a soil biologist, geologist, glaciologist and a couple of botanists.

At some point the Butcher Glacier cut across this area, creating a very unusual valley—about a mile long. The surroundings are mostly rock and ice so this “painfully lush” valley is quite an anomaly. The scientists are trying to determine how long it’s been ice-free.

The team was helicoptered in from Juneau and camped in the valley for six rainy days. Dave usually finds his beetles under rocks or at night on ice fields, but the lush valley produced very few finds. Fortunately, pit traps set-up on the valley floor were more productive.

Dave found very few beetles and almost no carabids (his specialty). Most were fully-winged finds, which could have flown in from the adjacent coastal lowlands, Dave says, or possibly even from nearby British Columbia. The one flightless beetle he found, however, is of special interest; its occurrence is unexpected and worthy of further study this fall.

Image: Dave Kavanaugh

The trick with most vertical or inverted walkers has to do with forces or sticky adhesives that work well on dry land, but not so much when things get wet and, well, slippery.

But two researchers, Stanislav Gorb of Kiel University in Germany and Naoe Hosoda of the National Institute for Material Science in Japan, decided to test the locomotion of Gastrophysa viridula, normally a terrestrial beetle, underwater. Ed Yong describes their submarine movements in Discover:

… once they touch the bottom, they can walk around very easily. Their footsteps aren’t precarious ones, either. While they don’t walk quite as easily underwater as they do on land, they can still produce a fair amount of force.

How are the beetles doing this? Bubbles, of course! The beetles use air bubbles trapped between their setae (the small hairs on the bottom of the beetles’ feet) to produce surface tension that creates stickiness underwater… At least for something the size of a beetle.

But wait, these bubbles probably do even more! Nature reports that

The bubbles themselves provide adhesion, but they may also de-wet the area around the beetles’ feet to allow the ‘hairs’ to function in the same way as they do in the dry.

Oils on the setae further enhance the adhesive effect.

So what next? Bio-inspired technology! Co-author Gorb explains their new environmentally-friendly, underwater adhesive, “Inspired by this idea, we have designed an artificial silicone polymer structure with underwater adhesive properties.” Microscopic bristles keep air trapped in the material, mimicking the beetles’ bubbles, keeping the material sticky underwater without using glue. Good ideas stick!

Images: Stanislav Gorb and Naoe Hosoda

In a surprising reversal of fortune, Israeli researchers have found a certain group of beetle larvae that feed on frogs.

As Ed Yong reports in his Discover blog:

During its lifetime, a frog will snap up thousands of insects with its sticky, extendable tongue. But if it tries to eat an Epomis beetle, it’s more likely to become a meal than to get one.

The larvae have shown 100% success in their ability to lure the frogs into becoming a meal. In fact, these beetles eat nothing else in the larval stage. Here are the gruesome details.

According to the researchers, Epomis larvae combine a sit-and-wait strategy with unique movements of their antennae and mouthparts to draw the attention of an amphibian (frogs and toads were used in the study). Thinking it has spotted potential prey, the amphibian comes closer and the larva increases the intensity of these enticing motions.

When the amphibian attacks, the larva manages to avoid the predator’s tongue and uses its unique double-hooked mouthparts to attach itself to the amphibian’s body and initiate feeding, which can include both sucking of bodily fluids and chewing body tissues, usually killing the much larger amphibian.

“It seems that instead of serving as food items for amphibians, Epomis larvae have evolved to specifically take advantage of amphibians as a food source,” says researcher Gil Wizen.

These findings extend the perspective of co-evolution in the arms race between predator and prey and suggest that counterattack defense behavior has evolved into predator-prey role reversal.

The research is published in the online journal PLoS ONE. Images and video of the beetle and the frightening attack can be found at Wired and Discover.

Image: Gil Wizen/AFTAU