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Archive for the ‘Biodiversity’ Category

There’s Something Fishy About These Bats

Posted by Richard Conniff on April 12, 2014

The long-fingered bat. (Photo: Antton Alberdi, UPV/EHU)

The long-fingered bat. (Photo: Antton Alberdi, UPV/EHU)

For researchers on the Mediterranean coast of Spain, near Valencia, the mystery began when bat excrement on the floor of a cave turned out to be loaded with scales, suggesting that an insect-eating bat species had instead turned to fishing.

It wasn’t a complete surprise. Bats are amazingly diverse, with 1,240 species (that’s 20 percent of all mammals), and they’ve had 50 million years to develop a multitude of quirky behaviors. Different bat species are known to eat almost anything—insects, of course, but also fruit, leaves, flowers, nectar, pollen, and, yes, blood. It might be genuinely surprising if somebody said bats catch and eat songbirds, except that researchers caught bats doing just that in 2007.

Frogs too. Early this year, researchers in Central and South America reported on how the male túngara frog’s love song produces a widening pattern of ripples on the surface of the water. Bats have learned to use that pattern as a flight path to cruise in and pluck up the unfortunate Lothario for dinner.

Still, Ostaizka Aizpurua-Arrieta and her coauthors on a new study in the journal PLOS One wanted to find out how Spain’s long-fingered bat learned to fish. “It was a special challenge for me because we didn’t think fishing was among the habits of the long-fingered bat,” says Aizpurua-Arrieta. These bats use echolocation to hunt down their main food source, immature midges, at the surface of the water. But the sonic pulses the bats emit for echolocation can’t penetrate below the surface, to where fish live. The long-fingered bat also weighs no more than a third of an ounce, which is “why it is difficult to imagine it fishing.”

And yet,

Read the rest of this entry »

Posted in Biodiversity, Cool Tools, Food & Drink | Tagged: , | Leave a Comment »

Hidden Superheroes of the Forest Underworld

Posted by Richard Conniff on April 7, 2014

A black-chinned red salamander in Georgia. (Photo: Todd W. Pierson/University of Georgia)

A black-chinned red salamander in Georgia. (Photo: Todd W. Pierson/University of Georgia)

My latest for the New York Times:

If someone asked you to name the top predator in North American forests, you might think of bears, or maybe great horned owls. But here’s another answer to think about: woodland salamanders.

These skittish, slippery amphibians literally live under a rock, or a log, or any convenient dark and damp forest habitat. As apex predators go, they are mainly small, a few inches long and weighing well under an ounce.

But they are hugely abundant — and very hungry. On an average day, a salamander eats 20 ants of all sizes, two fly or beetle larvae, one adult beetle and half of an insect called the springtail. And in doing so, they collectively affect the entire course of life in the forest — and perhaps far beyond.

According to a new study in the journal Ecosphere, salamanders play a significant role in the global carbon cycle. If flatulent cattle are among the black hats of climate change (the livestock industry emits 14.5 percent of human-associated greenhouse gases), then salamanders may just be the white hats, helping to stave off climate disaster. If no one has noticed this before, well, this is how it goes when you live under a rock.

A painted ensatina in northern California. (Photo: Todd W. Pierson/University of Georgia)

A painted ensatina in northern California. (Photo:
Todd W. Pierson/University of Georgia)

The study — by Hartwell H. Welsh Jr., a herpetologist at the United States Forest Service’s research station in Arcata, Calif., and Michael L. Best, now at the College of the Redwoods in Eureka, Calif. — notes that salamanders’ prey consists almost entirely of “shredding invertebrates,” bugs that spend their lives ripping leaves to little bits and eating them.

Leaf litter from deciduous trees is on average 47.5 percent carbon, which tends to be released into the atmosphere, along with methane, when the shredding invertebrates shred and eat them.

If there aren’t as many shredders at work and the leaves remain in place, uneaten, they are covered by other leaves, “like being trapped under a wet blanket,” as Dr. Welsh put it. The anaerobic environment under those layers preserves the carbon until it can be captured by the soil, a process called humification.

At least in theory, having more salamanders in a forest should mean Read the rest of this entry »

Posted in Biodiversity, Cool Tools, Environmental Issues | 1 Comment »

The Biological Warfare of Very Small Wasps

Posted by Richard Conniff on February 28, 2014

What a home invader looks like to a caterpillar

This is how a home invader looks to a caterpillar (Photo: José L. Fernández-Triana)

My latest for Takepart, the website of the movie company Participant Media:

Earlier this year, a study came out describing a new plant species in the Andes that is the sole home of an estimated 40 or 50 kinds of insects. I thought that had a certain “wow” factor. It also seemed like a chance to write about “keystone species”—the ones on which whole ecosystems depend—and the ripple effects when such a species goes extinct.

So I asked for a comment from evolutionary ecologist Dan Janzen at the University of Pennsylvania, and he responded with characteristic pith and vinegar. “You tell me what species on the planet is not an important part of the life cycle of many tens to hundreds of other species,” he demanded. “As for so-called keystone species, that simply means a species whose removal or other kind of perturbation happens to create a set of ripples big enough for a two-meter-tall, diurnal, nearly deaf, nearly dumb, nearly odor-incompetent, nearly taste-incompetent, urban invasive species”—that would be us, Homo sapiens—“to see, or bother to see, the ripple.” I let that project slide.

But a new study out this week in the journal Zookeys gives me a better idea of what Janzen was getting at. It describes 186 new species in northwestern Costa Rica, all parasitic wasps, the largest of them about half the length of my pinkie nail, and most—at one to five millimeters—much smaller. They’re certainly too small for most people to notice and too obscure to care about—except perhaps that each is a deadly master of a macabre kind of biological warfare.

First, the background. For more than 30 years, ecologists and parataxonomists—the foot soldiers in the science of species discovery—have been methodically prowling the Read the rest of this entry »

Posted in Biodiversity, Cool Tools | Tagged: , , , | 3 Comments »

Democracy Offers A Last Chance for Lemurs

Posted by Richard Conniff on February 20, 2014

Sahamalaza's blue-eyed black lemur (Eulemur flavifrons) in, northwest Madagascar. (Photo: Nora Schwitzer)

Sahamalaza’s blue-eyed black lemur (Eulemur flavifrons) in northwest Madagascar. (Photo: Nora Schwitzer)

My latest column for Takepart, the web site of movie company Participant Pictures:

Sahamalaza National Park in northwestern Madagascar is home to the strikingly beautiful blue-eyed black lemur—or to paraphrase its French name, “the lemur with the turquoise eyes.”

It’s a small, tree-dwelling creature, weighing less than four pounds, with a luxuriant tail that can be half as long as its body. It’s svelte and striking enough to appear on the cover of Vogue, and exotic enough for a music video with Lady Gaga. Yet this lemur remains almost unknown to the outside world. As a result, it is not just critically endangered, but one of the 25 most endangered primates in the world. With luck, a few thousand individuals may survive in the wild, almost all of them in three or four patches of forest in Sahamalaza National Park.

What’s happening to the blue-eyed black lemur is typical of the plight of the entire family of lemurs, 101 of the most colorful animals on the planet.  According to a new study published today in Science, 94 percent of all lemur species are now threatened, and many of them are Read the rest of this entry »

Posted in Biodiversity, Conservation and Extinction | Tagged: , , | 3 Comments »

A Field Biologist’s Vision of Heaven and Hell

Posted by Richard Conniff on February 19, 2014

A female P. reimeri cleaning her foot. (Photo: Piotr Naskrecki)

A female P. reimeri cleaning her foot. (Photo: Piotr Naskrecki)

The great field biologist Piotr Naskrecki has posted this item on his TheSmallerMajority blog:

Ever since I can remember I have been having a recurring nightmare: I am in some incredible location – usually somewhere in the tropics, there are amazing insects everywhere, often those that I have been dying to find, but I need to leave immediately and have none of my collecting gear – not a single vial, no net, no camera (not everybody can relate, I realize, but entomologists know what I am talking about). And last month I finally got to live through this bad dream.

A defensive display of Pardalota reimeri – these katydids feed on highly toxic plants and is likely that their bodies are loaded with poisonous alkaloids.

A defensive display of Pardalota reimeri – these katydids feed on highly toxic plants and is likely that their bodies are loaded with poisonous alkaloids.

Before coming to Gorongosa I flew to the northern town of Pemba where a newly opened campus of the University of Lurió trains Mozambican students in biology and engineering. It was supposed to be a strictly-business trip, meeting lecturers and students, and for this reason I did not bring with me any collecting or sound recording equipment, and only the most basic photo gear. But my friend Harith had a better idea and decided to take me on a short trip to Quirimbas National Park, famous chiefly for its spectacular marine life. Some of his students were working on insect and amphibian faunas of the park, and I said, “Why the hell not.” The seemingly easy trip turned briefly into hell after our Read the rest of this entry »

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Nine Simple Ways to Bring More Wildlife to Our Cities

Posted by Richard Conniff on February 4, 2014

A snowy owl perches on an office building in Washington, D.C., on Jan. 24. (Photo: Nathaniel Gran/The Washington Post via Getty Images)

A snowy owl perches outside an office building in Washington, D.C., on Jan. 24. (Photo: Nathaniel Gran/The Washington Post via Getty Images)

My latest for Takepart:

The spectacle of wildlife on city streets has been making the news lately, in ways both delightful and disturbing. It’s not just the snowy owls that have mysteriously decamped from the Arctic this winter to turn up in places like downtown Washington, D.C. It’s also the cosmopolitan coyotes living full-time in the Chicago Loop, and the mountain lion in Griffith Park, hemmed in by highways in the heart of Los Angeles. It’s the wild turkeys that some people now regard as “a scourge” in parts of New York City (though others remember when the species was almost eradicated from North America). It’s porpoises that recently swam up the Thames into the center of London, and the estimated 3,000 wild boars wandering around the streets of Berlin.

What’s going on here? It’s possible that urban wildlife enthusiasts, aided by camera traps and other new technologies, are simply revealing some of the wildlife that has always lived, unsuspected, all around us. But wildlife is probably also responding to larger changes in the landscape. One theory on snowy owls suggests that a surplus of lemmings in the Arctic has produced a bumper crop of owls, now spreading out into new habitat. The opposite theory says species are coming into the cities because they can no longer find the food and habitat they need in wilder terrain. That is, wildlife is being caught between landscapes that are, on one side, increasingly plowed under for intensive industrial agriculture and, on the other side, ever more sprawlingly urbanized.

In the United States, just in the 1990s, expanding urbanization ate up an area equivalent to Vermont and New Hampshire combined. By mid-century, cities and suburbs in the lower 48 states will occupy three times as much land as in 1990. Worldwide, 61 percent of people will live in urban areas by 2030, up from 29 percent in 1950, according to a United Nations report.

These changes mean cities and suburbs need to plan for wildlife, partly to minimize conflict, but mainly to welcome and promote newcomers to the neighborhood. “We must abandon our segregationist attitude toward nature—humans here, nature somewhere else,” says University of Delaware entomologist Douglas Tallamy.

Tallamy is part of a growing urban wildlife movement—with an agenda that ranges from promoting pretty songbirds in our backyards to providing essential ecosystem services to meet our own need for clean water, clean air, and food on our tables. Tallamy and other researchers suggest nine useful steps cities and home owners can take to become more wildlife friendly:

1. Bumblebees, honeybees, and other essential pollinators are in decline worldwide, and cities can help reverse that worrisome trend. In the United Kingdom, 60 cities have recently Read the rest of this entry »

Posted in Biodiversity, Cool Tools, Environmental Issues | Tagged: , , , , | Leave a Comment »

Why Farmers Must Grow Insects Like A Crop–Or Starve

Posted by Richard Conniff on February 3, 2014

One of our forgotten pollinators: Megchile fortis from Badlands National Park, South Dakota (Photo: USGS/Sam Droege)

One of our forgotten pollinators: Megchile fortis from Badlands National Park, South Dakota (Photo: USGS/Sam Droege)

For the last few years, Richard Rant has agreed to let researchers introduce strips of wildflowers among the blueberry plants on his family’s farm in West Olive, Michigan. It’s part of an experiment to see if the wildflowers can encourage pollinating insects and, in a small way, begin to reverse the worldwide decline in beneficial insects. It’s also a pioneering effort in the nascent movement to persuade farmers to grow insects almost as if they were a crop.

That movement is being driven by news that is disturbingly bad even by gloomy environmental standards. Insects pollinate 75 percent of the crops used directly for human food worldwide. They contribute $210 billion in agricultural earnings. But honeybees are now so scarce, according to a new study from the University of Reading, that Europe is 13.6 million colonies short of the number needed to pollinate crops there. Nor can farmers count on natural pollinators as a backup system. A 2011 study sampled four North American bumblebee species and found that they have declined by as much 96 percent over the past century. In China, the loss of wild bees has forced farmers to hand-pollinate apple blossoms using paint brushes.

The broad decline in beneficial insects has also affected species we take for granted as part of our cultural heritage. Just last week, researchers announced that monarch butterfly numbers, already at record lows, once again fell by half in the annual count at overwintering sites in Mexico, with the iconic monarch migration now “at serious risk of disappearing.”

So far, the movement to get farmers to grow beneficial insects amounts, in the United States, to no more than a few hundred thousand acres of pollinator plantings, mostly subsidized by state and federal governments. Through its Natural Resources Conservation Service, the U.S. Department of Agriculture (USDA) now partners with the Xerces Society and other conservation groups to get the message out to farmers and help them with the technical issues of how to grow beneficial insects, and how to get paid for doing it. USDA also recently added a pollinator component to the farmland set-asides it pays for through its Conservation Reserve Program. Similar programs are also under way as part of the European Union’s “agri-environment” schemes, Australia’s Landcare program, and the United Nations International Pollinator Initiative.

The experiment on Richard Rant’s blueberry farm — part of a research study by Michigan State University entomologist Rufus Isaacs — is an example of what can happen when such efforts work well. The study results are not expected to be published until later this year. But for Rant at least, planting for pollinators has seemed to work. He noticed that the wildflower patches were humming not just with bees and other pollinators but also with wasps, ladybugs, lacewings, and predacious beetles known to attack the sort of insect pests that damage blueberries. On his own, he started to add Read the rest of this entry »

Posted in Biodiversity, Conservation and Extinction, Environmental Issues | Tagged: , , | 6 Comments »

Holy Crap! These Are Some Scary Slave Raiders

Posted by Richard Conniff on January 11, 2014

ZooKeys-368-065-g001

These modern slave-raiders work on the eastern shore of Lake Michigan, up around Traverse City, Michigan, and the secret of their success is traveling light and quick.  They also employ chemical camouflage and have a deft way of murdering anyone that gets in their way.

European researchers discovered this astonishing behavior.  They’ve named the species Temnothorax pilagens, from pilere (Latin): to pluck, plunder or pillage. The paper is just out in the open access journal ZooKeysHere’s the press release

In contrast to the famous slave-hunting Amazon Ants whose campaigns may include up to 3000 warriors, the new slave-maker is minimalistic in expense, but most effective in result. The length of a “Pillage Ant” is only two and a half millimeters and the range of action of these slave-hunters restricts to a few square meters of forest floor. Targets of their raiding parties are societies of two related ant species living within hollow nuts or acorns. These homes are castles in the true sense of the word — characterized by thick walls and a single entrance hole of only 1 millimeter in diameter, they cannot be entered by any larger enemy ant.

An average raiding party of the Pillage Ant contains four slave-hunters only, including the scout who had discovered the target. Due to their small size the raiders easily penetrate the slave species home. A complete success of raiding is achieved by a combination of two methods: chemical camouflage and artistic rapier fencing.

The observed behavior is surprising as invasion of alien ants in an ant nest often results in fierce, Read the rest of this entry »

Posted in Biodiversity, Fear & Courage, Kill or Be Killed | 4 Comments »

How Did Monkeys Cross the Atlantic? A Near-Miraculous Answer

Posted by Richard Conniff on January 11, 2014

9780465020515_p0_v3_s260x420The question of how species came to live where they live is one of the enduring puzzles in biology: How did a big flightless bird like the now-extinct moa find its way to New Zealand?  How did monkeys cross the Atlantic from Africa?  Why does an insect-eating plant on a remote plateau in Venezuela have its nearest living relative at the other end of the Earth, in Australia?

Beginning in the 1960s, with the triumphant vindication of continental drift and plate tectonics, “vicariance” became the standard answer for evolutionary biologists. It’s what happens when a barrier—a mountain range, or an ocean, say—separates a species into two or more populations and sends them down diverging evolutionary paths. (The word comes from the Latin vicarius, meaning a thing that takes the place of something else, like a vicar standing in for a bishop.)

In this new view of geological history, all of the land masses of the modern world once huddled together in the ancient supercontinent Pangaea. As these land masses drifted apart to their present positions, they simply carried plants and animals with them—or so vicariance proponents argued.

To nonscientists, this may sound like a straightforward and not particularly controversial development in intellectual history.  But in his lively new book The Monkey’s Voyage: How Improbable Journeys Shaped The History of Life, biologist Alan de Queiroz reveals just how loaded it was with anti-establishment furor.

Vicariance, together with the ideas on which it was built, were “movements heavily fueled not just by intellectual considerations, but also by this radical belligerence that at times seemed like a stratagem,” Mr. de Queiroz writes. He enlivens his tale with vivid portraits of combatants, notably the Read the rest of this entry »

Posted in Biodiversity, Evolution | Tagged: , , | Leave a Comment »

Mystery of the War Elephants Solved

Posted by Richard Conniff on January 10, 2014

This artist's explanation was that North African forest elephants (left) are smaller than Indian elephants (right). (Source: wildfiregames.com )

This artist’s explanation was that
North African forest elephants (left) are smaller than Indian elephants (right). (Source: wildfiregames.com )

Scholars have been arguing almost forever over the “War of the Elephants,” which took place in 217 B.C. between Ptolemy IV, King of Egypt, and Antiochus III the Great, whose kingdom reached from modern-day Turkey to Pakistan.

The battle (also known as the Battle of Raphia) took place in what is now Rafah, in the southern Gaza Strip, on the border between present-day Egypt and Israel. It was the only known battle in which Asian and African elephants faced off against each other.  The great mystery, until now, was why historical accounts described the African elephants as smaller and less powerful than their Asian counterparts.

That never made much sense because we know that the largest African savannah elephants are bigger on average by about a half meter and 1000 kilograms. The historical account said Ptolemy, leading the army with the African elephants, had commandeered his elephants from what is now Eritrea, on the Red Sea, home to the northernmost population of savannah elephants. Some scholars (and the unknown artist for the illustration above) argued that he had obtained African forest elephants rather than savannah elephants.  Forest elephants are a closer match in size with Asian elephants, and research has recently demonstrated that they are a separate species from savannah elephants.

So did Eritrea have forest or savannah elephants?

Now a study in The Journal of Heredity proposes Read the rest of this entry »

Posted in Biodiversity, Fear & Courage, Kill or Be Killed | Tagged: | 1 Comment »

 
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