Conservationists in Egypt have discovered a new species of wolf, which shares DNA with Indian and Himalayan cousins.
The “Egyptian jackal”, as it’s known, is not in fact a jackal at all, despite the visual similarities it bears to another local species, the golden jackal. The discovery sheds light on how wolf species migrated through Africa and Europe — proving that grey wolves emerged in Africa about 3 million years before they spread to the northern hemisphere.
As long ago as 1880 it had been noticed that the Egyptian jackal looked suspiciously like the grey wolf. Several biologists in the 20th century, studying skulls, made the same claim. Still, the creature retained its name. Now, the difference has been formalized.
The next step for the team is to work out how many of the wolves exist in the wild. While Golden jackals aren’t threatened, it’s possible that the “Egyptian jackal” — which is now due for a renaming — is much rarer. Discovering the extent of the population, and where they live, will now be a priority.
Read more in the original article here.
Friday, January 28, 2011
Monday, January 24, 2011
Bioluminescent Creatures From the Sea
While a handful of land animals can create their own light, homemade luminescence is the rule rather than the exception in the open ocean's dark waters.
Researchers estimate that between 80%-90% of deep-dwelling animals are bioluminous, creating light by mixing the pigment luciferin with luciferase, the enzyme that makes it glow. The light tends to green and blue, colors that travel far in seawater. Glowing helps attract mates, lure prey or confound predators.
Many of these animals live thousands of meters deep and are difficult for scientists to find and study. Below are some of the prettiest and strangest glowing creatures of the seas.
For more, see the original article here.
Researchers estimate that between 80%-90% of deep-dwelling animals are bioluminous, creating light by mixing the pigment luciferin with luciferase, the enzyme that makes it glow. The light tends to green and blue, colors that travel far in seawater. Glowing helps attract mates, lure prey or confound predators.
Many of these animals live thousands of meters deep and are difficult for scientists to find and study. Below are some of the prettiest and strangest glowing creatures of the seas.
For more, see the original article here.
Thursday, January 20, 2011
Hidden Messages Found in Bird Nest Decorations
The discovery of messages in raptors’ nests has raised the possibility that many bird species encode signals into these structures, with seemingly decorative flourishes actually full of meaning.
Among black kites, scraps of white plastic are used to signal territorial dominance. To other kites, the scraps are a warning sign. To humans, they hint at an unappreciated world of animal communication.
A few species, such black wheatears and bowerbirds, are already known to use nest design in courtship displays. But such communication is considered uncommon and relatively one-dimensional, aimed entirely at finding a mate.
In a study published in Science, researchers describe their careful observations of 127 black kite nests in Spain’s DoƱana National Park.
They found that, several weeks before females laid eggs, birds festooned their nests with pieces of white plastic. Fitter birds, in possession of the best territory, tended to use more plastic. Weaker birds, with less-desirable territory, used less. Elderly and very young birds used none.
Territorial confrontations are common among kites, and proved closely linked to plastic displays. Kites with much plastic in their nest were rarely challenged, while those with little were challenged daily, even hourly.
The plastic appears to be a convenient way of codifying and announcing strength, saving kites from indiscriminate or ill-chosen battles. The birds also had access to green and transparent plastics, ostensibly preferring white because of its long-distance visibility.
When the researchers intruded, however, adding extra plastic to nests, challenges paradoxically became more frequent — suggesting that kite community is aware of existing claims, and quick to test would-be cheaters.
Read more in the original article here.
Among black kites, scraps of white plastic are used to signal territorial dominance. To other kites, the scraps are a warning sign. To humans, they hint at an unappreciated world of animal communication.
A few species, such black wheatears and bowerbirds, are already known to use nest design in courtship displays. But such communication is considered uncommon and relatively one-dimensional, aimed entirely at finding a mate.
In a study published in Science, researchers describe their careful observations of 127 black kite nests in Spain’s DoƱana National Park.
They found that, several weeks before females laid eggs, birds festooned their nests with pieces of white plastic. Fitter birds, in possession of the best territory, tended to use more plastic. Weaker birds, with less-desirable territory, used less. Elderly and very young birds used none.
Territorial confrontations are common among kites, and proved closely linked to plastic displays. Kites with much plastic in their nest were rarely challenged, while those with little were challenged daily, even hourly.
The plastic appears to be a convenient way of codifying and announcing strength, saving kites from indiscriminate or ill-chosen battles. The birds also had access to green and transparent plastics, ostensibly preferring white because of its long-distance visibility.
When the researchers intruded, however, adding extra plastic to nests, challenges paradoxically became more frequent — suggesting that kite community is aware of existing claims, and quick to test would-be cheaters.
Read more in the original article here.
Slime Molds Are Earth’s Smallest, Oldest Farmers
Colonies of a bizarre microbial goo have been found practicing agriculture at a scale tinier than any seen before.
Animals such as ants, snails and beetles are known to farm fungus. But the slime mold’s bacterial-farming trick takes it into a whole new realm.
Dictyostelium discoideum, the best-known of a group of creatures called slime molds, spends part of its life as a single-celled amoeba feeding on bacteria that grow in decomposing leaves on forest floors.
When food is short, hundreds of thousands of amoebas come together, fusing into a single entity. It may crawl off as a slug in search of richer pastures, then form a stalk topped by a “fruiting body” that bursts to disperse a few lucky amoebas-turned-spores. Or it may form the stalk right away, without crawling.
It’s been thought that slime molds simply scavenge, eating bacteria they like and oozing out the rest. In laboratories, researchers “cure” slime molds of their bacteria by allowing them to purge themselves on Petri dishes. But researchers kept finding bacteria in the fruiting bodies of some slime molds and not others.
When grown in the lab, the unusual fruiting bodies grew both the slime mold and the bacteria.
The team of scientists took new samples of different slime molds in the wild, growing them with careful attention to their dietary and excretory habits. They found that some strains didn’t gorge themselves and “lick the plate clean” of bacteria, but instead saved some inside of the colony. They were farmers, and fared better in some soils than their nonfarming counterparts.
Read more in the original article here.
Yellow Slime Mold Timelapse from sesotek on Vimeo.
Sunday, January 16, 2011
Smelly kudzu-eating bug invades Alabama
An invasive kudzu-eating bug that swept across Georgia last year has now been detected in Alabama.
Though you might be tempted to celebrate the arrival of a bug that eats kudzu, this bug stinks. Both literally and figuratively.
When temperatures drop, the pea-sized bugs -- also known as the lablab bug or the globular stink bug -- invades homes in hordes. When threatened or crushed, they emit a foul odor.
The bugs have been found as high as 30 stories up, coating the window sills of Atlanta condo high rises.
More seriously, the bug likes to munch on plants other than kudzu, including soybeans. It also could be a threat to other legume crops such as peanuts.
Auburn University researchers collected two individual specimens in east Alabama border counties, Cleburne and Cherokee. They now expect them to spread quickly across kudzu-rich Alabama.
Known scientifically as Megacopta cribraria, the bulbous, pea-sized bug is native to India and China. Researchers have not figured out how it got to Georgia. It might have caught a plane to Atlanta.
Kudzu itself is an Asian import. It was widely planted in the 1930s as an erosion prevention measure. When it found itself in a warmer and wetter world with none of its natural predators, kudzu quickly became a menace, spreading as much as a foot a day and eventually smothering anything that stood in its way.
Read more in the original article here.
Though you might be tempted to celebrate the arrival of a bug that eats kudzu, this bug stinks. Both literally and figuratively.
When temperatures drop, the pea-sized bugs -- also known as the lablab bug or the globular stink bug -- invades homes in hordes. When threatened or crushed, they emit a foul odor.
The bugs have been found as high as 30 stories up, coating the window sills of Atlanta condo high rises.
More seriously, the bug likes to munch on plants other than kudzu, including soybeans. It also could be a threat to other legume crops such as peanuts.
Auburn University researchers collected two individual specimens in east Alabama border counties, Cleburne and Cherokee. They now expect them to spread quickly across kudzu-rich Alabama.
Known scientifically as Megacopta cribraria, the bulbous, pea-sized bug is native to India and China. Researchers have not figured out how it got to Georgia. It might have caught a plane to Atlanta.
Kudzu itself is an Asian import. It was widely planted in the 1930s as an erosion prevention measure. When it found itself in a warmer and wetter world with none of its natural predators, kudzu quickly became a menace, spreading as much as a foot a day and eventually smothering anything that stood in its way.
Read more in the original article here.
Monday, January 03, 2011
Amazing World of Insect-Wing Color Discovered
A closer look at seemingly drab, transparent insect wings has revealed realms of previously unappreciated color, visible to the naked eye yet overlooked for centuries.
Until now, the wing colors of many flies and wasps were dismissed as random iridescence. But they may be as distinctive and marvelous as the much-studied, much-celebrated wings of butterflies and beetles.
Wasp and fly wings are made from two compressed layers of transparent chitin, with light bouncing off both layers and mixing to produce color. The same is true of oil slicks and soap bubbles, and scientists considered transparent wing coloration “a soap bubble iridescence effect, with randomly changing colors flashing over the wing surface,” according to scientists.
Instead, the researchers found that surface variations in chitin filtered out the iridescence. Remaining colors proved to be stable, and were visible from almost any angle. They differed consistently between species and sex.
Generations of biologists seem to have missed this partly because they didn’t look for it, and partly because the colors are most evident against a dark background. Against a white background, they’re invisible — which is exactly how most entomologists study transparent wings.
Researchers think the coloration has specific functions, particularly for mating, just as it does in butterflies and beetles and other insects with better-appreciated markings.
The patterns will also help scientists distinguish between species difficult to differentiate in other ways. Already the researchers used transparent wing colors to identify three new species of wasp.
Read more in the original article here.
Until now, the wing colors of many flies and wasps were dismissed as random iridescence. But they may be as distinctive and marvelous as the much-studied, much-celebrated wings of butterflies and beetles.
Wasp and fly wings are made from two compressed layers of transparent chitin, with light bouncing off both layers and mixing to produce color. The same is true of oil slicks and soap bubbles, and scientists considered transparent wing coloration “a soap bubble iridescence effect, with randomly changing colors flashing over the wing surface,” according to scientists.
Instead, the researchers found that surface variations in chitin filtered out the iridescence. Remaining colors proved to be stable, and were visible from almost any angle. They differed consistently between species and sex.
Generations of biologists seem to have missed this partly because they didn’t look for it, and partly because the colors are most evident against a dark background. Against a white background, they’re invisible — which is exactly how most entomologists study transparent wings.
Researchers think the coloration has specific functions, particularly for mating, just as it does in butterflies and beetles and other insects with better-appreciated markings.
The patterns will also help scientists distinguish between species difficult to differentiate in other ways. Already the researchers used transparent wing colors to identify three new species of wasp.
Read more in the original article here.
Parasites Make Caterpillars Glow to Repel Predators
Parasitic worms may be saving their own little hides when they induce the caterpillars they infest to glow a little and blush a furious red.
As the parasitic nematode Heterorhabditis bacteriophora infects caterpillars of the greater wax moth, the normally pale caterpillars temporarily bioluminesce and also turn persistently pink-red.
In outdoor taste tests with 16 European robins, birds overall preferred uninfected waxmoth caterpillars to ones that had been infected for at least three days. By the seventh day of infection, odd-colored caterpillars barely even got tentatively picked up by the birds.
It’s to the parasite’s advantage not to be eaten because these nematodes don’t infect vertebrates. So if a bird happens to eat a parasitized caterpillar, it’s bye-bye wormy.
Read more in the original article here.
As the parasitic nematode Heterorhabditis bacteriophora infects caterpillars of the greater wax moth, the normally pale caterpillars temporarily bioluminesce and also turn persistently pink-red.
In outdoor taste tests with 16 European robins, birds overall preferred uninfected waxmoth caterpillars to ones that had been infected for at least three days. By the seventh day of infection, odd-colored caterpillars barely even got tentatively picked up by the birds.
It’s to the parasite’s advantage not to be eaten because these nematodes don’t infect vertebrates. So if a bird happens to eat a parasitized caterpillar, it’s bye-bye wormy.
Read more in the original article here.
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