Some of us have enough trouble finding the food we want among the ordered aisles of a supermarket. Now imagine that the supermarket itself is in the middle of a vast, featureless wasteland and is constantly on the move, and you begin to appreciate the challenges faced by animals in the open ocean.
Thriving habitats like coral reefs may present the photogenic face of the sea, but most of the world's oceans are wide expanses of emptiness. In these aquatic deserts, all life faces the same challenge: how to find enough food. Now, a couple of interesting studies have shed new light on the tactics used by predators as large as sharks and as small as bacteria.
Big fish...
At a large scale, predators like sharks and tuna rely on chemical cues to give away the location of their prey. Sharks are particularly expert trackers, but powerful though their super-senses ...
