“I was at a conference, and a colleague was talking about the locomotion of great apes in the trees,” says Lewis Halsey, a physiologist at the University of Roehampton in London. The colleague mentioned that it’s tough to measure how these animals use energy. That’s when Halsey had an epiphany. “I was working with parkour athletes on another project,” he says, studying how much energy the athletes used while jumping and climbing around a city. Why not use these human athletes to stand in for tree-living apes?
In the forests of West Africa, bands of handsome primates called Diana monkeys roam the tree branches. Each group has just one male and several females with their babies. The tradeoff for his apparently cushy living situation is that the male has to chase off predators. His female companions use specific calls to tell him what kinds of threats are nearby. And he responds to whatever they tell him—even if it goes against his own judgment.
Is your dog a natural athlete or a couch pup-tato? The answer might depend on how far removed it is from its wild ancestors. Dogs that are more similar to wolves have kept more of their natural athleticism, while breeding has rendered other types of dogs a little…less impressive.
Caleb Bryce, a PhD candidate at UC Santa Cruz, says his study of canine athletes came about serendipitously. “We were just hoping to calibrate a new wildlife collar we’ve developed,” he says; he planned to test the collars on “a dog or two” before using the technology to study how wolves use energy. But the collars revealed so much variation between those dogs in energy use that Bryce and ecophysiologist Terrie Williams decided to investigate further.
The researchers looked at 23 adult dogs, divided into three groups. One was “northern breeds,” or sled dogs: these included Siberian huskies, Alaskan malamutes, and Samoyeds. Another group was Plott hounds, a dog bred for tracking game by scent. The third group was made up of retrievers, including golden retrievers and labs. Read More
Superman donned glasses to disguise himself and blend in with other people. One snake hides its identity using a similar trick: when threatened, it changes the shape of its pupils. This makes it resemble a much more dangerous animal.
The mock viper (Psammodynastes pulverulentus) is mild-mannered, not superpowered. Read More
Italy’s school for water rescue dogs, the Scuola Italiana Cani Salvataggio, has trained hundreds of animals in canine heroics. The dogs work on Italian police and coast guard boats, and with fire departments and the navy. They can even jump into the ocean from a hovering helicopter to save a person.
They’re pros at taking commands from humans. So researchers wondered if the dogs could help them understand what kind of command works best: Words? Or gestures? Read More
Don’t look now, but this spineless sea creature may be able to count better than your toddler.
Cuttlefish need to be savvy if they want to eat. They’re always on the lookout for shrimp, fish or crabs. When a cuttlefish spots a potential victim, it shoots out two specialized, sucker-bearing tentacles and nabs it. Since these hunters have to make constant judgments about which prey are worth targeting, it would make sense for them to have advanced cognitive skills—say, the ability to count.
To find out whether this was true, Tsang-I Yang and Chuan-Chin Chiao, of Taiwan’s National Tsing Hua University, brought some Sepia pharaonis cuttlefish into the lab for a math exam. Read More
“I don’t know what you’re talking about,” said the polar bear. “Everything seems normal to me! Watch out for that puddle.”
Up in the Arctic, things are getting slushy. But some polar bears are refusing to change their ways. Instead of compromising on where they spend their time, they’re clinging to the icy habitats they’ve always loved. As those habitats keep shrinking, though, the bears will eventually find things too crowded and uncomfortable to ignore. Read More
The goblin shark is a weird deep-sea creature first discovered off the coast of Japan in 1898. It has a ghoulish appearance, thanks to jaws that can stretch well away from the rest of its head. Scientists have assumed the goblin shark uses this trick to eat—but until recently, no one had actually watched one catching prey in the wild.
In 2008 and 2011, divers working with the Japanese television broadcaster NHK managed to capture two goblin sharks (Mitsukurina owstoni). Before rereleasing the animals, they made five video recordings of the sharks striking and eating—in one case, a shark was taking a swipe at a diver’s arm. Now Kazuhiro Nakaya, of Japan’s Hokkaido University, and others have analyzed that footage frame-by-frame to try to understand how a goblin shark does its thing. Read More
Some babies are born totally useless (I’m looking at you, Homo sapiens). Others can wobble upright shortly after birth and start teetering around. And still other animals are almost frighteningly precocious.
For example, the metallic livebearer, a little golden fish native to Cuba, hatches from an egg while still inside its mother. That means the mom gives birth to live young. The more traditional fish-y way is to lay eggs. But some other fish also bear live young, including guppies and most kinds of sharks.
Metallic livebearers (Girardinus metallicus) are hunters very with precocious babies. As soon as a newborn G. metallicus swims into the world, it’s ready to murder. Read More
If you’re ever lost in a remote European forest, you might be able to get your bearings by finding a herd of roe deer. These animals like to align themselves roughly north-south, whether they’re standing still or fleeing danger.
Roe deer are small, reddish or grayish grazers common in Europe and Asia. Petr Obleser, of the Czech University of Life Sciences in Prague, and his coauthors studied the behavior of these skittish herbivores to look for evidence that they can sense the earth’s magnetic field. Read More