Small fish may have small brains, but they're not stupid. A common coral reef fish called damselfish can learn to avoid predators from more experienced kin, even in complete darkness, new research shows.
Biologists have long known that fish use a variety of signals to warn others when predators approach, including visual cues, chemical cues, warning sounds and cues felt by motion. Until now, visual cues were thought to be an essential part of the mix. But new work from a team of biologists from Australia and Canada has shown otherwise, as reported today in the journal Proceedings of the Royal Society B.
Many fish can often detect an approaching predator by its distinct odor. Some are born hardwired to associate the smell of predators with danger, whereas others are born oblivious and must learn to make the connection. [See Images of Freaky-Looking Fish]
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