Fish feel the flow

New model explains how these swimmers use their lateral lines to read wakes

Special sensory cells in fish respond reliably to swirly wakes, allowing fish to hunt down prey or join a friendly school by reading the watery traces, a paper to appear in Physical Review Letters suggests.

As fish, and other objects, move through water, they leave behind long-lasting vortices, or wakes, says study coauthor Jacob Engelmann of Bonn University in Germany, like the residual swirls left by a canoe paddle in a lake.