海洋植物逃离捕食者

A rabbit might outrun a fox, but stalks of wheat aren’t making any quick getaways. Plants, for the most part, don’t flee from predators.

But some primitive marine plants are breaking the rules. Marine scientists at the University of Rhode Island School of Oceanography recently discovered a species of phytoplankton that actively avoids being eaten.

The scientists observed that the phytoplankton, called Heterosigma akashiwo, swam away from zooplankton, its natural predator, yet remained undaunted by the presence of predators with an appetite for other things.

What’s more, when the scientists provided an area that the predators couldn’t tolerate—sort of a safe haven if you will—the phytoplankton took refuge in that location. They also avoided empty water that had previously contained predators, leading researchers to believe they’re responding to some sort of chemical signal. The discovery is published in the journal PLoS ONE. [Elizabeth L. Harvey and Susanne Menden-Deuer, Predator-Induced Fleeing Behaviors in Phytoplankton: A New Mechanism for Harmful Algal Bloom Formation?]

It was already known that phytoplankton could to move toward light and food, but this is the first time they’ve been known literally to go out of their way to avoid being a meal themselves.

—Gretchen Cuda Kroen