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The Glaucus atlanticus sea slug, or blue dragon, feeds on toxins from much larger species. Taro Taylor / Getty Images

This tiny creature has gotten a fair bit of attention lately because of one simple reason: It’s absolutely crazy-looking. At first glance, it resembles a Pokémon or character from Final Fantasy more closely than a real biological animal. But the Glaucus atlanticus sea slug—commonly  known as the blue sea slug or blue dragon—is indeed a genuine species. And if you swim in the right places off of South Africa, Mozambique or Australia, you just might find one floating upside down, riding the surface tension of the water’s surface.

The species has a number of specialized adaptations that allow it to engage in a surprisingly aggressive behavior: preying on creatures much bigger than itself. The blue dragon, typically just an inch long, frequently feeds on Portuguese man o’ wars, which have tentacles that average 30 feet. A gas-filled sac in the stomach allows the small slug to float, and a muscular foot structure is used to cling to the surface. Then, if it floats by a man o’ war or other cnidarian, the blue dragon locks onto the larger creature’s tentacles and consumes the toxic nematocyst cells that the man o’ war uses to immobilize fish.

The slug is immune to the toxins and collects them in special sacs within the cerata—the finger-like branches at the end of its appendages—to deploy later on. Because the man o’ war’s venom is concentrated in the tiny fingers, blue dragons can actually have more powerful stings than the much larger creatures from which they took the poisons. So, if you float by a blue dragon sometime soon: look, but don’t touch.

Image courtesy of Jon Sullivan, Wikimedia Commons.

Imagine an army of spies so tiny it could go almost anywhere undetected. The U.S. Department of Defense already has. For years their technology development arm, DARPA, has been working to create insects that will move where they’re directed. But forcing insects to go where you want them to is just half the battle. To outfit them with electronic devices—like miniature video cameras or sensors to detect poison gas, for example—you need a lightweight power source.

Last week, a team of researchers led by chemist Evgeny Katz of Clarkson University reported that they had successfully implanted biofuel cells into brown garden snails. To extract energy, the team poked electrodes through the snail’s shell into the blood-like liquid called hemolymph that lies below. The enzyme-coated electrodes harvest energy from glucose and oxygen in the hemolymph.

The snails couldn’t generate much energy, about 0.5 Volts. But Katz says the electrical energy could be stored in a condenser and then released to power an external device. In fact, that work is already underway in his lab. The next step, Katz says, is to create an organism that can power an attached micr0-sensor capable of monitoring the environment. Slow-moving snails aren’t exactly the ideal soldier, but Katz and his colleagues are also studying other organisms that might be better suited to military applications.

Other groups are working on implantable biofuel cells as well. Earlier this year, researchers successfully implanted biofuel cells in the abdomens of cockroaches, which move at a much quicker clip. And, according to Nature news, another research group accomplished the same feat in beetles.

Fuel cells aren’t the only way to get energy from small organisms. Scientists are also using piezoelectric materials, which generate current when deformed, to convert the mechanical motion of bugs’ wing beats into electricity. And in 2009, a team of scientists developed a moth fitted with a transmitter powered by radioactive isotopes. Moths have been a favorite with the Department of Defense. According to the Washington Post, in 2007 DARPA program manager Amit Lal talked about Gandalf using a moth to call for air support when he was trapped in The Lord of the Rings. “This science fiction vision is within the realm of reality,” he noted.

Last year, a team of researchers reported that they could steer a moth’s flight by attaching a neural probe to the insect’s ventral nerve cord. Check out this video of the moth in flight. Combine that technology with the power-producing biofuel cells, and the reality Lal envisions may not be so far off.

I have glimpsed the future. And it is teeming with creepy crawly cyborgs. Shudder.

At first glance, the sawfish looks like nature’s awkward version of a double-sided garden rake. This highly endangered species is a kind of ray. Previous observations of sawfish predatory behavior pinned them as slow-moving bottom-dwellers.

But a study this month in Current Biology shows that the freshwater sawfish is no rake-nosed dope. In fact, the sawfish uses its toothed rostrum (the saw) not only to detect its next meal, but also to attack and impale its prey, sometimes slashing at schooling fish or even cutting tissue out of whales. Their strikes can be strong enough to cut a fish in half.

The study shows that the saw is used both to detect prey and to attack it. Other fish in the shovel-nose family can’t do both—and previously, researchers thought the sawfish followed suit. Unlike other jawed fish whose snouts are used for one or the other purpose, the sawfish has thousands of electroreceptors that enable them to detect the electromagnetic field produced by other animals, and they have tiny canals on their skin that register water movement in their three-dimensional hunting environment.

This new reputation may lead to changes in fishing practices allowed in sawfish territory—their saws often become entangled in fishing gear, contributing to their swift decline.

Image courtesy of Gary Kramer, U.S. Fish and Wildlife Service

The gray wolf has been taken off the federal endangered species list three separate times in the past 9 years. In each case, wolf advocacy groups persuaded courts to intervene, and the wolf ended up back on the list. On December 21, the U.S. Fish and Wildlife Service officially delisted the wolf yet again in Wisconsin, Michigan and Minnesota. And many environmentalists hope that this time the decision will stick.

Over the past several decades, the wolf population in the Great Lakes region has skyrocketed. In 1985, Wisconsin had just 14 wolves. Today the state has roughly 800. More than 4,000 wolves live in the region, most in Minnesota.

Wolves tend to steer clear of humans, so keeping track of their numbers can prove challenging. How do scientists know how many are out there? Sometimes they talk to them. In the summer and fall, they conduct howling surveys. Biologists and volunteers drive the roads at night, stopping at regular intervals to howl. At each stop, they record their location and whether they got a response from real wolves. They write down how many wolves or pups howled back. These surveys provide information on the wolves’ whereabouts, abundance and pup production. A few years ago, I accompanied expert howler Adrian Wydeven, a mammalian ecologist at the Wisconsin Department of Natural Resources.

Check out the audio clip to hear him howl like a wolf:

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As the number of wolves has grown, so too has the number of wolf-human conflicts. Attacks on people are exceedingly rare, but wolves do kill dogs, cattle, sheep and other livestock, angering landowners. When the wolf was on the federal endangered species list, states couldn’t do much beyond compensating people for their losses.

The wolf’s delisting, which took effect January 27, “will make it easier to deal with problem wolves,” Wydeven says. “This allows federal trappers to trap at sites where wolves have attacked pets or livestock. It allows landowners to defend their pets and livestock.” And landownders with a history of wolf depredation problems can apply for a special permit that allows them shoot wolves on their property. Having that flexibility provides enormous comfort to landowners and “really  leads to very few wolves being killed,” he says. Since the wolf came off the list, “we’ve  issued almost 70 permits,” Wydeven says. So far, only one wolf has been shot by a permit holder.

Many major environmental groups are hailing the delisting as a step in the right direction. The Natural Resources Defense Council calls the delisting date, “a good day for wolves and for national wolf conservation policy.” Defenders of Wildlife and National Wildlife Federation are on board too.

But the controversy over Wisconsin’s wolves is far from over. Last week, the state assembly passed a bill that, if signed by Governor Scott Walker, would allow wolf hunting and trapping. “I’m guessing he probably will support it,” Wydeven says. The Great Lakes Indian Fish and Game Commission, a tribal resource management agency representing 11 Ojibwe tribes, opposes the bill for cultural and religious reasons.

Whether the bill passes or not, Wisconsin and neighboring states will closely monitor wolf populations in the coming years. Wydeven relies on mostly on radio collars and, in the winter, he and a team of volunteers scan the ground for wolf tracks. In the summer and fall, of course, Wydeven will continue to howl.

Japanese honeybees surround a giant hornet. Image courtesy of Masato Ono, Tamagawa University

For millions of years, Japanese honeybees have been locked in a deadly battle with the Japanese giant hornet, a fierce predator with an appetite for bee larvae. With a two-inch-long body and a 3-inch wingspan, the hornet is enormous – many times larger than the bees. But the honeybees have evolved a unique defense mechanism: When a hornet invades a honeybee hive, as many as 500 bees gang up and form a tight ball around the attacker. The heat from the bees’ vibrating wings and the carbon dioxide they respire proves a deadly combination. In less than an hour, the hornet is dead.

The attack unfolds like this: When a hornet approaches a honeybee hive, bee guards posted at the entrance fiercely shake their abdomens. In a paper published last month, researchers argue that this abdomen shaking represents an “I see you” signal, something that is advantageous to both predator and prey. “The prey avoids attack, the predator avoids chasing a prey that has been alerted,” the researchers write. If the waggling doesn’t deter the hornet, the guards alert the rest of the hive. Some of the worker bees exit the nest and wait outside. If the hornet moves to attack, these bees surround it, forming a “hot defensive bee ball.”

Hot bee ball. Image courtesy of Masat Ono, Tamagawa University.

A new study, published last week, examines what goes on in the honeybees’ brains while they are in this ball. The researchers, including Takeo Kubo of the University of Tokyo and Masato Ono of Tamagawa University, first identified a gene whose expression could be used as a marker of brain activity. They then used a live hornet tied to a wire to spur the formation of a bee ball. When they inserted the hornet into the hive, the bees swarmed and the researchers managed to extract the bee ball and place it in a beaker. That enabled them to pluck individual bees from the pile at different time points and examine their brains for increased expression of the target gene. (See a video of the process here.)

The balling behavior seemed to prompt activity in particular neurons found in bee brain regions called the mushroom bodies, which are involved in learning and memory. Heat exposure alone led to increased activity in these same neurons. What this means isn’t yet entirely clear. The researchers speculate these neurons may help the bees monitor how hot the ball gets and avoid overheating.

One thing is clear: The balling behavior seems vital to the bees’ survival. European honeybees, which were introduced in Japan more than a century ago, have not evolved any defense mechanisms against giant hornets. Hornet attacks can devastate their hives; a group of 20 to 30 hornets can slaughter a 30,000-bee colony in just a few hours.