If you want to protect rare species, first you have to find them. In the past few years, biologists have developed a powerful new tool to do that. They've discovered that they can often find traces of animal DNA in streams, ponds — even oceans.
The idea took root just five years ago, when biologists in France found they could detect invasive American bullfrogs simply by sampling pond water and looking for an exact genetic match to the frogs' DNA.
Divers Shawn Stamback and Francis Antigua had a much closer encounter than they expected off the coast of central California on Saturday when two humpback whales surfaced just a few feet away from where they were swimming.
Dolphins are like humans in many ways: They're part of complex social networks and, just as in people, a dolphin's brain is big, relative to the size of its body. But there's something else, too — a study published Monday shows these acrobats of the sea use name-like whistles to identify and communicate with each other.