The Dance of the Dung Beetles

After they have gathered a ball of dung, but before they wheel it away from the dung heap, dung beetles always climb on top and spin around in a little dance.  It looks like a moment of triumphant celebration, and one we can all identify with as we slog through our version of the same old shit.  But it turns out they are actually just taking a compass reading.

Here’s the report from Science Daily:

Dung beetle dance provides crucial orientation cues: Beetles climb on top of ball, rotate to get their bearings to maintain straight trajectory.

The dung beetle dance, performed as the beetle moves away from the dung pile with his precious dung ball, is a mechanism to maintain the desired straight-line departure from the pile, according to a study published in the Jan. 18 issue of the online journal PLoS ONE.

The purpose of this dance, in which the beetle climbs to the top of the ball and rotates, had previously been unknown, so the authors of the PLoS ONE study, led by Emily Baird of Lund University in Sweden, investigated the circumstances that cause the beetle to dance.

They found that the beetles are most likely to perform the dance before moving away from the pile, upon encountering an obstacle, or if they have lost control of the ball, suggesting that the behavior is crucial for keeping the ball moving in a straight line.

Such direct, efficient navigation allows the beetle to quickly move away from the intense competition from other beetles at the dung pile. The authors propose that the beetles store a compass reading of celestial cues during the dance, which they then use to guide their straight-line trajectory.

So it’s all about geography, not poetry.  Even so, musicians, rise up!  We need a modern-day Bela Bartok or Edvard Grieg to celebrate this particular peasant dance.

 

Emily Baird, Marcus J. Byrne, Jochen Smolka, Eric J. Warrant, Marie Dacke. The Dung Beetle Dance: An Orientation Behaviour? PLoS ONE, 2012; 7 (1): e30211 DOI: 10.1371/journal.pone.0030211

Games Pigs (and Primates) Play

The notion of Dutch pig farmers being obliged to hang around devising ways to entertain their pigs sounds like something out of Orwell, or maybe PETA’s Kafkaesque vision of hell for factory farmers.  You can imagine some poor guy in overalls doing his best standup routine (“Two pigs and a priest walked into a bar …”), only to have the displeased or merely bored pigs declare, “We are not amused,” followed by 30 days in a box cage.

But according to a recent press release from The Netherlands:

Since 2001, European legislation has made it compulsory for pig farmers to provide entertainment in the pens to combat boredom, aggression and tail biting amongst pigs, which will hopefully eliminate the need for routine tail-docking. Farmers have been experimenting with all kinds of materials and games, but in practice it proves difficult to provide the animals with an adequate challenge.

And now, to the rescue, just as the impatient pigs are about to declare “Off with their heads,” come the amusing folks at the Utrecht School of the Arts (HKU) and Wageningen University and Research Centre, with a computer game that allows pigs and people to play together. “Pig Chase” employs what looks like a huge widescreen tv in the rearing pen with light effects that enable the pigs to interact with a human player, who uses an iPad.  The press release continues:

Not just people but also pigs like to play. It was already known that pigs are capable of mastering a simple computer game, for example. The innovative aspect of this research is the idea of getting people and pigs gaming together. Thereby they might offer each other

How a Soda Tax Could Save 26,000 Lives a Year

The American addiction to soda has vast consequences for our waistlines and our lives.   (The obesity crisis also matters to the health of the planet).  Now a study by researchers at  Columbia University and the University of California San Franciso say a modest soda tax could save 26,000 lives a year.  Here’s the press release:

Newswise — Every year, Americans drink 13.8 billion gallons of soda, fruit punch, sweet tea, sports drinks, and other sweetened beverages—a mass consumption of sugar that is fueling soaring obesity and diabetes rates in the United States.

Now a group of scientists at the University of California, San Francisco (UCSF), San Francisco General Hospital and Trauma Center (SFGH) and Columbia University have analyzed the effect of a nationwide tax on these sugary drinks.

They estimate slapping a penny-per-ounce tax on sweetened beverages would prevent nearly 100,000 cases of heart disease, 8,000 strokes, and 26,000 deaths every year.

“You would also prevent

Wake up, Lysenko, Tell Lamarckists the News

In an article being published tomorrow in Cell, scientists have demonstrated that an acquired trait can be inherited, without any DNA involvement.  It’s the second time in recent days that scientists have hinted that Lamarckism may be more than wishful thinking.

The idea that an organism can pass on  to its offspring  traits acquired during its lifetime was an early theory of evolution, put forward by the eminent French naturalist Jean-Baptiste Lamarck (1744-1829).  The idea fell into disrepute after the 1859 Darwin-Wallace discovery of evolution by natural selection.   But it became a deeply dangerous idea–and Soviet national policy–in the hands of a twentieth-century follower of Lamarck, Trofim Lysenko.  He argued, among other things, that he could soak wheat in frigid water and alter its DNA to make future generations more resistant to the harsh Russian winters.  Under Stalin, criticism of Lysenkoism could get legitimate scientists arrested or even killed.

But now researchers are focusing on factors outside the DNA that may alter the expression of certain genes, and it seems that an individual can acquire changes in how these factors function and pass those changes on to subsequent generations. Last week, Australian scientists described a preliminary study in mice, not yet published in a peer-reviewed journal, suggesting that  obese Dads can pass on a tendency to obesity to their offspring.  The researchers even suggested that prospective dads should consider losing a few pounds before trying for kids.  (No harm in that, but, hey, lose it for your own sake.)

The new study from Cell is of course peer-reviewed.  It’s about acquired immunity to disease, a subject with potential for profound evolutionary effects.  But for now the researchers mostly stick to their study animal,  a worm.  Here’s the press release:

Columbia University Medical Center (CUMC) researchers have found the first direct evidence that an acquired trait can be inherited without any DNA involvement. The findings suggest that Lamarck, whose theory of evolution was eclipsed by Darwin’s, may not have been entirely wrong.

The study is slated to appear in the Dec. 9 issue of Cell.

“In our study, roundworms that developed resistance to a virus were able to pass along that immunity to their progeny for many consecutive generations,” reported lead author Oded Rechavi, PhD, associate research scientist in biochemistry and molecular biophysics at CUMC. “The immunity was transferred in the form of small viral-silencing agents called viRNAs, working independently of the organism’s genome.”

In an early theory of evolution, Jean Baptiste Larmarck (1744-1829) proposed that species evolve when individuals adapt to their environment and transmit those acquired traits to their offspring. For example, giraffes developed elongated long necks

The Water is Not Fine

Anyone who has ventured alone in remote and difficult corners of the planet knows that discovering new species entails a considerable dose of danger and also tedium, wonder and also absurdity, discomfort and also loneliness.  My book The Species Seekers is full of such stories, but I just came across a couple that ended up on the cutting room floor:

Fossil-hunter Louis Leakey described the experience of sharing a water hole with large animals at his camp in East Africa’s Olduvai Gorge this way:  “We could never get rid of the taste of rhino urine even after filtering the water through charcoal and boiling it and using it in tea with lemon.”

And botanist Joseph Banks contemplated his own death in a ship, The Endeavour, hung up on the Great Barrier Reef, in June 1770: 

“The most critical part of our distress now approached … if (as was probable) she should make more water when hauld off she must sink and we well knew that our boats were not capable of carrying us all ashore, so that some, probably the most of us, must be drownd:  a better fate maybe than those would have who should get ashore without arms to defend themselves…”

The indomitable Capt. James Cook eventually managed by considerable effort to get Endeavour off the reef and into a safe harbor for repairs, and Banks made it back to London alive.

As to the taste of rhino urine, I am pretty sure Leakey just learned to live with it.

Mommy, Who’s for Dinner Tonight?

Natalie Angier writes today about animal cannibalism, starting with research  by Richard Shine at the University of Sydney in Australia  about cane toad tadpoles gobbling up cane toad eggs:

Significantly, the tadpoles weren’t simply hungry for a generic omelette. Reporting in the journal Animal Behaviour, Dr. Shine and his co-workers showed that when given a choice between cane toad eggs and the similar-looking egg masses of other frog species, Rhinella tadpoles overwhelmingly picked the cannibal option. Oh, little cane toads lacking legs, how greedily you snack on pre-toads packed in eggs!

Life after metamorphosis brought scant relief from fraternal threats. The scientists also demonstrated that midsize cane toads wriggle digits on their hind feet to lure younger cane toads, which the bigger toads then swallow whole. “A cane toad’s biggest enemy is another cane toad,” Dr. Shine said. “It’s a toad-eat-toad world out there.”

Rhinella’s brutal appetite is among a string of recent revelations of what might be called extreme or uncanny cannibalism, when one animal’s determination to feed on its fellows takes such a florid or subversive turn that scientists are left, as Mark Wilkinson of the Natural History Museum in London put it, “gobsmacked” by the sight.

There are males that demand to be cannibalized by their lovers and males that seek to avoid that fate by stopping midcourtship and hammily feigning rigor mortis. There are mother monkeys that act like hipster zombies, greeting unwanted offspring with a ghoulish demand for brains; and there are infant caecilians — limbless, soil-dwelling amphibians — that grow fat by repeatedly skinning their mother alive.

In the past, animal cannibalism was considered accidental or pathological: Walk in on a mother rabbit giving birth, and the shock will prod her to eat her bunnies. Now scientists realize that cannibalism can sometimes make good evolutionary sense, and for each new example they seek to trace the selective forces behind it.

Why do cane toad tadpoles cannibalize eggs? Researchers propose three motives. The practice speeds up maturation; it eliminates future rivals who, given a mother toad’s reproductive cycle, are almost certainly unrelated to you; and it means exploiting an abundant resource that others find toxic but to which you are immune.

“We’re talking about a tropical animal that was relocated to one of the driest places on earth,” Dr. Shine said. “Cannibalism is one of those clever tricks that makes it such a superb colonizer and a survival machine.”

You can read the full article, in which she describes male black widow spiders being eaten by the females after sex as “arachinirvana”  here.  I think it would be nerve-wracky-nirvana, no?

Momofuku’s Swamp Yankee

Strusinski on the prowl. (Photograph by Andrew Hetherington)

This is a story I wrote about edible biodiversity for the October issue of Outside Magazine.

ONE DAY IN MAY, in a venerable old cemetery somewhere in northwestern Connecticut, a trio of food professionals clusters around a handsome pitch pine tree delicately infused with essence of dead New England farmer. The three of them are greedily plucking pale green buds and stuffing them alternately into plastic baggies and into their mouths. “These are fucking good,” says a test-kitchen chef from the Momofuku restaurant empire. “Great texture!” a colleague agrees.

Evan Strusinski, who makes his living foraging wild foods, steps back and sizes up the tree as if he means to collect the whole damn thing. He eyes the car in which they arrived and asks, “Does this Prius have a roof rack?” Then he eats a few more pine buds and his voice pitches up like Regina Spektor singing about tangerines: “Oh! They’re so poppy! So juicy! They inspire me to nibble.”

“Put it in light syrup, focus on the texture,” the Momofuku guy riffs. “Pine poppers! Serve ’em on ice cream.” Later they notice the lemony-tasting sheep sorrel on a hilltop nearby, and all of them drop to their knees as though in worship.

A certain lunatic enthusiasm for wild foods tends to infect people who go foraging with Strusinski, especially when he is in his usual hunting grounds, in the mountains of Vermont or on the coast of Maine. It’s contagious: Strusinski, a boyish 39-year-old with curly, uncombed hair and a now-and-then beard, will be digging edible roots with his bare hands and suddenly whoop, “I feel like a wild pig foraging for truffles!” Or he’ll push back his battered fedora and start to sing as he works his scissors deftly through the perfect threadlike scapes in a sloping field of ramps—“I’m going to be rich”—and then speculate on how many scapes it will take to procure the 1972 Toyota Land Cruiser of his dreams. (The idea is not entirely far-fetched: he recently

California Acts to Ban Shark Fin Soup

A few months back, I was annoyed by an NPR show that seemed to be turning a proposed ban on shark fin soup into an attack on the Chinese community.  Never mind that the bill was being sponsored and backed by people of Chinese ethnicity.  And never mind that it was about the highly destructive practice of cutting the fins off living sharks and tossing them back in the water to die.

Now California has done the right thing and passed the ban–meaning a slight but significant reduction in pressure on seriously threatened shark populations.

Here’s the press release:

SACRAMENTO, Calif. Sept. 6, 2011 — Yesterday, the California Senate passed Bill 376, which would ban the sale and trade of shark fin in the state of California. The Center for Oceanic Awareness, Research, and Education (COARE), applauds the California State Senate for joining them in actively addressing shark conservation issues, and playing a major role in reducing shark fin consumption in the U.S. and worldwide.

Assembly Bill (AB) 376 was introduced to the California State Assembly on 14 February 2011 by Assemblymembers Paul Fong (D-Cupertino) and Jared Huffman (D-San Rafael), and subsequently passed the Assembly on 23 May 2011 with a vote of 65-8.  Yesterday the bill passed the Senate with a vote of 25-9, and the bill now moves on to the governor for action.

California is now one step closer to helping the West Coast of the United States enact a full ban on the trade of shark fins, which will help reduce pressure on rapidly declining shark populations.  California’s proposed ban complements similar legislation recently signed into law in Washington State and Oregon, and is also preceded by legislative bans adopted by the State of Hawai’i, Guam, and the Commonwealth of the Northern Mariana Islands (CNMI).

California is one of the largest sources of demand for shark fin outside Asia and is a major entry for shark fin distribution in the United States.  This legislation represents a significant step towards

An Efflorescence of Flamingoes

American flamingo by J.J. Audubon

Natalie Angier on flamingoes, in today’s New York Times:

Now they paraded forward, now they all marched aft. Now they shot up their necks like periscopes and twisted their heads first left, then right. They flashed the black petticoats of their underfeathers in single- and double-winged salutes. They moonwalked on water, raised a spindled leg balletically, from dégagé position to arabesque. They honked like indignant Canada geese and rasped like didgeridoos.

She also explains how flamingoes feed and why they so often stand elegantly on one leg:

Wherever they alight, flamingos are filter feeders, the avian equivalent of baleen whales. They skate slowly through their chosen wetland, as stiff and pompous as Monty Python’s philosophers on a soccer field, treading through mud and water with their webbed feet, panning for brine shrimp, algae, insects, larvae, whatever the local microbios may be.

A flamingo submerges its head upside down,

A Parasite that Tricks a Rat into Becoming a Cat’s Dinner

This is a good one, from Louis Bergeron at the Stanford University news service:

When a male rat senses the presence of a fetching female rat, a certain region of his brain lights up with neural activity, in anticipation of romance. Now Stanford University researchers have discovered that in male rats infected with the parasite Toxoplasma, the same region responds just as strongly to the odor of cat urine.

Is it time to dim the lights and cue the Rachmaninoff for some cross-species canoodling?

“Well, we see activity in the pathway that normally controls how male rats respond to female rats, so it’s possible the behavior we are seeing in response to cat urine is sexual attraction behavior, but we don’t know that,” said Patrick House, a PhD candidate in neuroscience in the School of Medicine. “I would not say that they are definitively attracted, but they are certainly less afraid. Regardless, seeing activity in the attraction pathway is bizarre.”

For a rat, fear of cats is rational. But a cat’s small intestine is the only environment in which Toxoplasma can reproduce sexually, so it is critical for the parasite to get itself into a cat’s digestive system in order to complete its lifecycle.

Thus it benefits the parasite to trick its host rat into putting itself in position to get eaten by the cat. No fear, no flight – and kitty’s dinner is served.