The snow monkeys of Japan are famous for an adaptation that only they exhibit: soaking in Nagano's hot spring bathing pools. It looked like they were trying to stay warm, but it was only recently that scientists investigated. Rafaela S.C. Takeshita and her colleagues at Kyoto University tested levels of glucocorticoids, which increase with stress. The monkeys who bathed in winter had a cortisol concentration that was 20 percent lower on weekly average than for those that did not bathe. "Japanese monkeys tend to become more aggressive in the winter, and the cold temperature should also contribute to higher stress levels. But, like human beings, hot spring bathing may have reduced them," Takeshita said.

How dinosaurs lived

Gigantic dinosaurs frolicked 170 million years ago in the lagoons of what is now Scotland. That's what paleontologists determined after discovering jumbo-sized footprints belonging to long-necked sauropods on the Isle of Skye. Mixed with the herbivores' tracks were clawed impressions from two-legged meat-eaters known as theropods. The footprints give a snapshot of life in an era that has yielded relatively few fossil remains. Identifying two types of footprints in the same place also challenges the idea that long-necked dinosaurs waded into shallow waters to escape predators, said Stephen Brusatte, a paleontologist. "We're actually seeing these dinosaurs interacting with each other and interacting with their environment."

When songbirds swim

For Kate Stafford and other oceanographers, ocean noise is as complex as the sounds of a jungle. And bowhead whales — 75-ton mammals that can live two centuries — are the world's biggest songbirds. She said that bowhead whales near Greenland are part of the small group of animals that make complex "singing" sounds. The best comparison, she said, is a jazz musician, riffing. "We humans, most of us are visual animals," Stafford said. "Underwater, light doesn't travel very far. Chemical cues don't travel very far. …Sound is really the way animals are going to navigate and find food and find mates." That is, by the way, what Stafford believes the complex whales songs are all about: finding mates.