Shape Shifter

 

(Photo: Cally Harper)

Tongues can do delightful and astonishing things. I am thinking of the way a frog fires its sticky tongue halfway across the universe to snag a passing insect (see below). Or how an alligator snapping turtle wriggles its tongue like a worm as a dinner invitation to fish. And now the Pallas’s long-tongued bat (Glossophaga sorcina) joins this elite club of astonishing animal tongue artists.

These bats, found from Argentina to northern Mexico, and sometimes into Arizona and New Mexico, have the fastest metabolism ever recorded in a mammal, says a 2007 study in the journal Nature. They burn half their body fat each day, and have to make up for it at night by consuming as much as 150 percent of their body weight in nectar from flowers. And of course, they have to do it on the wing. According to a study published today in the Proceedings of the National Academy of Science, the secret to its success is a remarkable ability to change the shape of its tongue into a hemodynamic—or blood-swollen—“nectar mop.”

When lead author Cally Harper, a doctoral candidate in biomechanics at Brown University in Rhode Island, began her study, specialists already knew that bats of this species have an unusual fringe of hair-like structures around the tip of the tongue.  They assumed these were useful for collecting nectar—but passively, like raking icing off a cake using your fingernails. Biologists also knew that these bats have enlarged blood vessels in their tongues. But they didn’t know what to make of them. Harper had a hunch that the two features might be connected, especially since …  Read the full article here.

Fur, Feathers, and Pharmaceuticals

The pharmacist is in

House sparrows and finches pad their nests with nicotine-laced cigarette butts to reduce mite infestations.  Wood ants do the same sort of thing with an antimicrobial resin from conifer trees, preventing microbial growth in the colony. Monarch butterflies infected with parasites protect their offspring from that irritating fate by laying their eggs on anti-parasitic milkweed.  (Well, if they can find any milkweed.)   And baboons exploit a well-stocked medicine chest, treating parasitic infections with the fruit of the Balanites tree, halting bouts of diarrhea by eating leaves from the Sodom apple, and relieving menstrual cramps by munching on the leaves of the candelabra tree.

“When we watch animals foraging for food in nature, we now have to ask, are they visiting the grocery store or are they visiting the pharmacy?” says Mark Hunter, co-author of an article on “Self-Medication in Animals,” published online today in the journal Science. “We can learn a lot about how to treat parasites and disease by watching other animals.

“Perhaps the biggest surprise for us was that animals like fruit flies and butterflies can choose food for their offspring that minimizes the impacts of disease in the next generation,” says Hunter, can ecologist at the University of Michigan. “There are strong parallels with the emerging field of

Tiger Cub: Ready for My Closeup

Camera traps are such a spectacular way to see animals in the wild without disturbing them.  Here’s the latest example.

The press release is from the Wildlife Conservation Society (WCS):

NEW YORK  (March 27, 2012) — A 4-5 month old tiger cub examines a remote camera last month in India’s Bhadra Tiger Reserve, a protected area where tiger numbers are increasing. The second camera can be seen in the background.

WCS conservationists, led by tiger expert Ullas Karanth, conduct annual surveys in the region, photographing and identifying individual tigers by their unique stripe pattern. WCS has been working in Bhadra Tiger Reserve since the late 1980′s. WCS’s partners led by DV Girish and other local conservationists have strongly pushed for increased protection in the reserve, and fought against forest exploitation, illegal settlements, and development projects that would have damaged the area.

Scientific data collected by WCS show that on account of conservation measures, prey numbers have doubled and tiger numbers are on the rise. Bhadra stands out as a model of tiger conservation success that affirms the value of the ‘source site’ strategy advocated by WCS for recovering wild tigers.

The Fine and Bloody Art of Hedgerows

(Photo: Campaign to Protect Rural England)

This is a piece I wrote in England in about 1994.  It’s dated in terms of hedgerow destruction, and protection.   (You can read an update here.  And there are some additional links at the end of the article.)   But I’m reprinting it on the hunch that some of the characters I met then are vanished types in the British countryside, and the crofters now probably all have iPhones.

“That’s a good hedge,” the farmer said,  walking along a dense field border of hawthorn and beech, somewhere in the north of England.  “It’s a grand habitat for things to creep in.”  It was October, and the hawthorn were thick with bright red berries that songbirds would harvest over the winter.  Here and there, a blackthorn was hung with fat, blue sloe berries.  (“Three pounds of sloes, two pounds of sugar, and one bottle of gin,” said the farmer, giving his recipe for sloe gin.  “I was telling a fella the other day that it’s three-two-one, and he said, ‘What, three bottles of gin?”)  There were rosehips that moth caterpillars had mined out for sustenance, and others, still intact, that field mice would climb up to strip bare for seeds in the middle of February.

Britain’s hedgerows are, in truth, an excellent place for things to creep in, a long, thin bramble-and-thorn habitat.  They are living fences populated by a Wind in the Willows community of moles, voles, badgers, weasels, and shrews.  Roughly 60 bird species nest or feed in hedges, including white throats and black caps up from Africa for the summer, and redwings down for the winter from Scandinavia.  So do hundreds of invertebrate species.  Bats roost in tree hollows by day and cruise the hedgerows for dinner by night.  Hedgehogs, despite their name, generally prefer household gardens.  But hedge sparrows are commonplace in hedges, making mossy nests full of beautiful pale blue eggs.  Indeed, for many species, hedges are the only available habitat.

“There is no natural habitat left in the United Kingdom,” says Colin Barr, who oversees a nationwide “countryside survey” for the Institute of Terrestrial Ecology.  “There is some semi-natural habitat, meaning little or no current interference by man–for instance, the sub-arctic plateau in Scotland.”   But the forests in many upland areas are actually government-sponsored plantations–often little more than tree farms.  And in the intensively-farmed lowlands, hedges and a few stream borders are the only habitat–indeed, often the only vegetation that hasn’t been plowed flat.  “So it follows,” says Barr, “that hedges are seen as particularly important.”

But hedgerows have always been a sort of shadow habitat, a habitat almost by accident.   They existed in the first place because farmers needed them, perhaps as far back as the Bronze Age more than 5000 years ago, to separate and shelter their livestock.   Hedgerows divided the countryside into a patchwork of small fields, creating a landscape that the poet Andrew Marvell once called “the garden of the world.”  But when farmers no longer needed the hedgerows,

Using the Smell of Rotting Meat to Find New Species

New breed of field biologist (Photo: Ernie Cooper)

Science magazine online recently reported a bizarre technique for finding new species:  By the smell of their rotting flesh.   The idea is to let carrion flies do the work of field biologists:

Even today, the distribution and abundance of many animal species remains poorly documented, and figuring out a habitat’s who’s who is no easy task. The terrain can be vast and difficult to traverse, and many creatures are secretive by nature. Traditionally, biologists have searched for the animals themselves, or for burrows, nests, footprints, droppings, and other traces—and all that searching can be time-consuming and costly. In recent years, they’ve been turning to labor-saving methods, such as setting out microphones, cameras, and traps that snag hairs, or studying animal DNA left behind in water or soil.

But why not just let someone else do the searching? Carrion flies—which include blowflies (family Calliphoridae) and flesh flies (family Sarcophagidae)—live around the world in virtually every terrestrial habitat occupied by vertebrates. Best of all, they’re abundant and much easier to capture than vertebrates—even dead ones.

“In the rainforest, many animals die each and every day, but it’s really rare to find a carcass,” says Sébastien Calvignac-Spencer, an evolutionary biologist at the Robert Koch Institute in Berlin and lead author of the new study.

Calvignac-Spencer and colleagues collected carrion flies in two tropical habitats: Taï National Park rainforest in Côte d’Ivoire and dry, deciduous Kirindy forest in Madagascar. They began by analyzing flies they captured under mosquito nets shrouding dissected mammal carcasses of known species, showing that DNA from the carcasses could be retrieved from the flies.

They then trapped 115 flies at random in the two forests and found that 40% contained identifiable DNA fragments from a total of 20 mammal taxa, two bird species, and an amphibian. In Kirindy, the catch represented 13% of the documented mammal community. In Taï, the mammals aren’t fully cataloged, but the scientists turned up DNA from six out of nine known primate species and one very rare antelope, they report this week in Molecular Ecology. Those results are “remarkable” for a modest sample, according to a commentary in the same issue.

You can read the full article by Rebecca Kessler here.  She also mentions recent research using leeches for the same purpose.  Visit this website for more information on the dashing field biologist in the photo.

Fashionable Slime

Sooner or later we all have to eat our words, and today it’s my slimy turn.  Here’s part of what I wrote about slime eels, also known as hagfish, in my 1996 book Spineless Wonders:  Strange Tales of the Invertebrate World:

Among other habits that have endeared them to seafarers, slime eels like to enter dead or dying bodies on the ocean bot­tom by way of mouth, gills, or anus, and gobble up everything except bones and skin, which remain intact. Fish immobilized in gill nets are particularly susceptible. In one study in the Gulf of Maine, slime eels gutted 3 percent to 5 percent of the catch. J. B. Heiser, a biologist at Cornell University’s Shoals Marine Laboratory in Maine, describes what’s left of the fish as “a bag of bones, literally . .. like it had been sucked dry by a high- powered vacuum cleaner.”

Slime eels are often still inside the fish when the bloated gill net spills its contents onto the fisherman’s deck, and Heiser, who has opened up several specimens, says the hags ensconced in their victim are typically well-fed and at ease, “smiling, slimy, usually snoring—gently.” In one case, the record, a single cod contained 123 slime eels, in a pink, wriggling mass.

It is a disheartening sight for fishermen, touching some source of horror beyond mere economic loss. One fisheries ex­pert has attributed this horror to the slime itself: “Being worth­less . . . the hag is an unmitigated nuisance, and a particularly loathsome one owing to its habit of pouring out slime from its mucous sacs in quantity out of all proportion to its small size. One hag, it is said, can easily fill a two-gallon bucket, nor do we think this any exaggeration.”

But, oh, how wrong, how terribly narrow-minded, of both me and my nameless expert, because hagfish slime is apparently destined to become the stuff of high fashion.  ScienceDaily reports:

Nylon, Kevlar and other synthetic fabrics: Step aside. If new scientific research pans out, people may be sporting shirts, blouses and other garments made from fibers modeled after those in the icky, super-strong slime from

Why Flies? Maybe for Fish Farm Feed

Salmon feeder? (SEM by MicroAngela)

In my book Spineless Wonders: Strange Tales of the Invertebrate World, I included a chapter with the headline, “Why Did God Make Flies?”

Now we know, thanks to this intriguing report from NPR’s Eliza Barclay.  Recycled maggots, anyone?

What’s the lowly house fly got to do with the $60 billion fish farming industry?

Quite a lot, says Jason Drew, a jet-setting British entrepreneur who is so enthusiastic about the potential of flies, he’s just written a book called The Story of the Fly and How It Could Save the World. He thinks flies can solve one of aquaculture’s most vexing issues: what to feed the growing ranks of farmed fish.

Farm-raised salmon, trout and shrimp need a lot of animal protein in their diet. Right now, that protein comes mainly from small, wild fish that are turned into fish meal. It takes about 3 pounds of fish to produce 1 pound of farmed salmon, and as we continue to deplete wild fish stocks, fisheries experts say we’re going to run out.

And so aquaculture experts all over the world are scrambling to figure out what to do about it.

A few years back, Drew was checking out some farms in Saudi Arabia that were exporting chicken and shrimp to South Africa, where he lives. He saw all the fish meal going to feed those creatures, and got to thinking just how unsustainable it was.

He also noticed, he says, that “the price of fish meal was moving in one direction only: up. Unless we find a new sea.”

At a slaughterhouse in Saudi Arabia, he stumbled upon what could become the new sea: a huge pond of blood, buzzing with flies. After consulting with some scientists, Drew became convinced that flies could recycle

Elephant Poo Air Conditioning

Dung beetle in booties

Apparently, elephant excrement is the next best thing to a Frigidaire window unit, if you are a dung beetle, according to researchers studying how the beetles roll balls of dung across the desert to their nest, in South Africa:

“The beetles climb on top of their moist balls whenever their front legs and heads overheat,” said Prof. Marcus Byrne from Wits University. “We stumbled upon this behaviour by accident while watching for an ‘orientation dance’ which the beetles perform on top of their balls to work out where they’re going. We noticed that they climbed their balls much more often in the heat of the midday sun.”

Further experiments showed that this midday phenomenon only held true when the beetles were crossing hot ground. In fact, beetles on hot soil climb their balls seven times as often as those on cooler ground.

To show that it was the beetles’ hot legs that made them climb the ball, the researchers applied some cool (as in temperature) silicone boots to their front legs as alternative protection from the heat. “To our great surprise, this actually worked, and beetles with boots on climbed their balls less often,” said Dr Jochen Smolka from Lund University, who collaborated on the research.

You have to love any study that involves putting booties on dung beetles.  And one last bit of ickiness:

Once on top of a ball at midday, the beetles were often seen “wiping their faces,” a preening behavior that the researchers suspect spreads regurgitated liquid onto their legs and head to cool them down further. That’s something the insects never do at other times of day.

Source:  Jochen Smolka, Emily Baird, Marcus J. Byrne, Basil el Jundi, Eric J. Warrant, Marie Dacke. Dung beetles use their dung ball as a mobile thermal refuge. Current Biology, 2012; 22 (20): R863 DOI: 10.1016/j.cub.2012.08.057

Duelling with a Flick-Knife Frog

Flick knife (by yunalee)

A Japanese researcher (and presumptive anime fan) has revealed how a frog can flick out sharp spikes from a false thumb for both combat and mating.

Noriko Iwai from the University of Tokyo, studied the Otton frog (Babina subaspera), on the Amami islands in southern Japan.  Unlike most frogs, Otton has a fifth digit, a sort of pseudo-thumb, containing the switchblade spikes.  Science Daily reports that the thumb serves mainly to hang onto the female in the muddy throes of amphibian love-making:

“While the pseudo-thumb may have evolved for mating, it is clear that they’re now used for combat,” said Dr Iwai. “The males demonstrated a jabbing response with the thumb when they were picked up, and the many scars on the male spines provided evidence of fighting.”

The conditions on the Amami islands make combat, and the need for weaponry, a key factor for the frogs’ mating success. Individuals fight over places to build nests, while the chances of a male finding a mate each night are rare, thus the ability to fight off competitors may be crucial.

Sadly, the frogs don’t face off as in the rumble scene from “West Side Story”  (or, to stick with anime, like Spike versus Vicious).  Instead, they

Another Defenseless Caterpillar to Scare the Piss out of You

It’s the caterpillar of the imperial fruit sucking moth (Pyllodes imperialis) in northern Queensland, Australia.   But it looks more like something Ridley Scott dreamed up for “Alien,” then discarded as just a little too creepy.