Blogs / Discoblog

One of the great scientific questions has finally been answered: Can grizzly bears dance? Yes—and rather well, thank you very much. Researchers from the USGS have released video footage taken during the past two years of grizzly and black bears shimmying against tree trunks in Northwest Montana as if the very soundtrack of Saturday Night Fever was playing in the background.

Okay, these beasts are not really dancing. The bears (males primarily) are leaving their chemical “signature” behind on so-called rub trees to communicate with other males and avoid turf wars while searching for breeding females. Investigators recorded at 16 different sites in Glacier National Park and plan to use the footage to better understand bear behavior and improve experimental methods. Dance-off, anyone?

Click here to watch the video

When Montana State University plant pathologist David Sands first proposed that some bacteria that infect plants could spread over great distances through falling precipitation, some thought his idea was crazy. But new research says Sands’ idea actually holds water.

Bacteria, including one species known to infect tomato and bean plants, are found in greater abundance in freshly fallen snow than previously thought, says Brent Christner at Louisiana State University, who led the new research. Christner examined snow from sites with lots of vegetation nearby (France) and places with no vegetation (like Antarctica). He found bacteria in snow no matter where he looked. In some samples, 85 percent of the particles found in the snow were bacterial.

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Tuna has been getting a lot of attention lately, but for all the wrong reasons. In January, a popular front-page article in the New York Times found frighteningly high levels of mercury in tuna from Manhattan sushi restaurants. The consumer’s response? It still tastes good (and it’s not like we’re eating thermometers). New Yorkers were wise to detect an element of sensationalist scaremongering in the Times article, but now there’s a genuine, urgent reason to avoid that succulent sushi: Tuna is facing regional extinction. Thanks to worldwide demand for “the chicken of the sea,” tuna populations have been plummeting despite efforts at sustainable fishing.

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As sharks face intense fishing–with over a million killed each year for their prized fins and for meat–shark researchers sketched out the state of the ocean’s top predators and wondered about their future.

Julia Baum studies the great sharks: large top predators including hammerheads, tiger sharks, great whites, bull and dusky sharks, oceanic whitetips, blues, threshers, and mako. All of these species have declined more than 80% in just the last 20 years, and many species have been cut down by 90% or more. Many are already listed as vulnerable or endangered by the IUCN.

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For all their mystery, we know two things about the world’s oceans pretty well: One, they’re huge, and two, they do a lot for human beings (producing food, storing carbon, allowing travel and shipping, and scads of other good stuff). But just how much is a particular patch of healthy, functioning ocean real estate worth to humanity? And how can we decide on the places that are most important to protect, and how to balance the dozens of competing demands on the waters around us? This morning’s Marine Symposium saw a line-up of top marine ecologists grappling with how to start quantifying and valuing the “ecosystem services” performed by ocean environments. (more…)

It may not be long before sharks invade Antarctic waters. Due to global warming the Antarctic seas are changing and becoming an inviting ground for sharks that will soon turn to the prey-rich southern waters, says Cheryl Wilga of the University of Rhode Island.

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Today at the Hynes Convention Center in the heart of Boston, AAAS went “Into the Deep” with a symposium exposing deep-sea coral as an ancient organism (older than you’d think), a tool that can be used to measure climate change, and a victim of trawling, disappearing at an alarming rate.

Deep-sea corals may be the oldest known organisms in the ocean, says Brendan Roark, a geochemist from Stanford University. The oldest among them were once thought to be about 1,800 years old, but Roark’s new radio carbon dating studies show they can be as old as 4,200 years. The key to the new evidence was provided in the finding that these corals grow much more slowly than previously thought–it takes one species over 700 years to grow an inch. Flying in the face of conventional thinking, Alberto Lindner of the University of Sao Paulo in Brazil says that deep-sea corals are actually the ancestors of their shallow-water cousins. Warm, sunlit shallow seas were once thought to be the cradles of coral diversity. But Lindner’s DNA evidence shows that the more familiar shallow water corals, such as those that form the Great Barrier Reef, are actually the new comers on the evolutionary scene. (more…)

Answers in Genesis, the folks who brought us the Creation Museum, just launched a “professional, peer-reviewed technical journal,” Answers Research Journal. Because after all, peer-reviewed journals are where real scientists publish their work, right? Splendid. Let’s pop inside and take a peek at how peer review works for creationists!

Here is the publication’s own description of the review process, from their Instructions to Authors [PDF]:

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Scientists have determined that shipworms, a wormlike-species of clam, use air as their source of protein. Shipworms have long been known to eat boats and historical landmarks, but wood only provides them with sugar; like termites, shipworms have symbiotic bacteria that can digest cellulose into sugar molecules. But to a shipworm, a diet of wood is like a diet of Pixy Stix—just gobs of carbohydrates and calories. Biologists didn’t understand where the clams were getting their protein, and hence, how they were able to survive. (more…)

Scientists at MD Anderson Cancer Center have created mice with long, slender, bat-like fingers in place of their short, stubby little paws. Unlike the stunning quail-duck, or “quck”—which was cobbled together with gnarly Face/Off-esque transplants—researchers created the “mouat” by simply replacing a small section of DNA from the mouse version to the bat version. This section is responsible for regulating the levels of a single protein in the developing limb—with the protein at elevated bat levels, the mouse’s fingers grew long and slender.

The mouats are far from taking flight—it takes more than long fingers to make functional wings—but they may help solve the evolutionary mystery of bats, the only flying mammals. The fossil records show a sudden appearance of mammals nearly identical to modern bats about 50 million years ago—with no transitional forms—providing ample fodder for ID-ists. This study shows that a small change to the expression of a single gene—not even a change to the gene itself—may have instigated the evolution of mammalian flight.

The FDA has finally ruled that food from cloned animals is as safe as food from those produced by conventional reproduction, and will not require a special label (except, perhaps, in California). The 968-page report, released Tuesday, details these peer-reviewed findings, which also conclude that cloning does not pose any unique risks to the animals, compared with other reproductive techniques.

But cloned meat and dairy still won’t be available at the supermarket for a while—the USDA is asking for a “voluntary moratorium” on sales to allow the consumer marketplace to get over their revulsion towards genetic modification. This “ick” factor, which seems to dominate the arguments against cloned meat, may stem largely from misunderstanding the cloning process.

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Carbon dioxide may be the greenhouse gas we hear about most often, and with good reason: It’s by far the most abundant heat-trapping culprit produced by human sources, and it’s also one that individuals can do a lot to reduce.

But methane is actually 20 times more powerful as a greenhouse gas than carbon dioxide, and about 18 percent of methane from human activities is produced in the guts of our livestock (released mostly via belching, not the back end).

Kangaroos, on the other hand, don’t produce the stuff. So now, researchers in Australia want to reduce methane from cattle and sheep by introducing digestive bacteria from kangaroo guts into livestock. They say they’re still a few years away from a successful transfer. Meanwhile, other options under investigation for cutting cow methane include garlic supplements in feed (yum, pre-seasoned beef), or just using feed plants that are easier to digest.

If only the cows would listen, too…

And lest you’re starting to wonder about your own digestive contributions, fear not: according to the EPA, methane emissions from the human body are insignificant.

That’s the name of a book. It’s about intelligent design. It’s for idiots who don’t understand intelligent design.

Presumably, they read the book and then become idiots who push intelligent design.

Remember that scene at the end of The Matrix when Keanu Reeves dives headlong into the Agent Smith’s torso and writhes around inside? It turns out some cells in the human body can do something pretty similar—except without the whizzy special effects. Harvard researchers today described a new cellular process—they named it entosis—where one cell bores into another. Most of these interlopers die inside the other cell, but some survive and leave after a brief romp inside the host—and some even divide within the other cell.

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Certain East African male cichlids, a kind of freshwater fish, have evolved a really odd way to increase their little sperms’ chance of reproductive success. The game plan goes as follows:

1. Females of these species lay their eggs before they’re fertilized and then gobble them up and store them in their mouths to keep them safe.
2. The males need to get their sperm into an egg-filled mouth to have fish babies. It might work if they just put flung their sperm out there in the water near a female, but that’s a bit of a shot in the dark (water).
3. So the males’ anal fins have evolved to have spots that look like cichlid eggs. The females (displaying the notorious fish intelligence) think the spots are their own eggs, so they come over to eat ‘em.
4. The males then squirt out their sperm, which the females unintentionally gobble down, thinking maybe they’re eating their own eggs.

How long before teachers and parents start adding these East African cichlids to their explanations to young ‘uns about the birds and bees?

When you look at a picture of Paris Hilton, don’t you feel all warm and fuzzy inside, as if all pain were leaving your body? If so, you have something in common with male mice, for whom looking at a picture of the tabloid queen has a painkilling effect.

But if you’re more like me and looking at a picture of the heiress gives you the heebie jeebies, you’ll feel better once you hear researchers’ explanation for this analgesic effect: The scientists suspect that the picture of Paris is really just stressing the mice out. They think she’s a predator (with those stilettos, they’re probably right). And when mice get scared, pain takes a backseat to their more important survival instincts. The reason the effect is only seen in male mice is that females don’t sweat it as much. Other research backs this up: In a number of situations, girl mice don’t seem to respond as strongly to threatening stimuli.

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In the play “Lucy,” an emotionally distant anthropologist (Lisa Emery) decides that her severely autistic daughter Lucy (Lucy DeVito) is not sick. Instead, says the hermit scientist, she is the future: Lucy’s lack of connection to other human beings is actually an evolutionary leap forward. The rest of us? Obsolete—mental health fossils.

Our anthropologist supposes that hypersociality has created a poisonous overgrowth of society curable only by turning inward, and that autism (the diagnosis of which has increased tenfold) arose to accomplish that.

Thanks for the science, but she’s wrong.

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This story is almost too strange. Some cells taken from a woman’s cervical cancer continued to divide and live on, indefinitely, through today and—to all appearances—far into the future. She died 56 years ago, yet the cells from her body are still used widely in cancer research and also helped in the cure for the polio vaccine.

The oddest thing about it is that the cells do everything an organism needs to do (e.g., self-propagate, consume, excrete) so scientists say it’s a new species—that evolved from this woman’s cancer cells while in her body! I think this is exceedingly strange.

The Wikipedia article has a bunch of good links, if you don’t quite believe it (as I didn’t, at first).

The Independent reports on the discovery of potent antibiotic powers in a combination of smectite and illite excavated from French volcanic mountains—yes, clay that can cure disease. In lab tests, the magic muck wiped out 99 percent of methicillin-resistant Staphylococcus aureus, the same stuff that was recently revealed to kill more Americans than HIV.

Thus far researchers have little idea why it works: “We have multiple working hypotheses,” says Arizona State clay expert Lynda Williams—which is a good scientist’s way of saying, they have no frickin’ idea what’s going on. More puzzlement: “Our primary hypothesis is that the clay minerals transfer elements, not yet identified, to the bacteria that impede their metabolic function.”

An interesting alternate hypothesis is that the clay kills by some physical mechanism, as does bleach or ammonia. That would be most welcome news, because it means bacteria would not easily evolve resistance.

A fish called a great swallower lived up to its name when it tried to eat a snake mackerel that was a full four times its own length off the coast of the Cayman Islands. A passing fisherman spotted the weird fish-in-a-fish and brought it back to Cayman Department of the Environment.