Some sea creatures can find their way through thousands of miles of seemingly featureless oceans. Even more impressive is the route that they take. "Well, we've known for a long time that sharks are capable of long-distance migrations, and in some cases those migrations occur along very straight paths." Scripps Institution of Oceanography biologist Andy Nosal. "And this has always begged the question: how exactly do they know where they're going?...So, there have been a lot of hypotheses floated over the last several decades, including the idea that these sharks are using, for example, geomagnetic cues, chemical cues and others. But none of these have really been systematically tested in the field." Nosal and his team suspected that the navigational secret of some sharks might be their sense of smell. They use their keen noses to find food, of course. And other fish, like salmon, are known to use olfaction to navigate. To see if his hunch was right, Nosal scooped up some adult female leopard sharks in their preferredt environment, waist-deep water off the San Diego coast.