Revealing the secret lives of creatures, big and small

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."

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.