New understanding of how fish use a “sixth sense” to detect flows of water helps resolve a long-time mystery about how the creatures respond to their environment.
“We identified a unique layout of flow sensors on the surface of fish that is nearly universal across species, and our research asks why this is so,” explains Leif Ristroph, an assistant professor at New York University’s Courant Institute of Mathematical Sciences and one of the study’s authors.
“The network of these sensors is like a ‘hydrodynamic antenna’ that allows them to retrieve signals about the flow of water and use this information in different behaviors.”
It’s well known that fish respond to changes in their fluid environment. These include avoiding obstacles, reducing swimming effort by slaloming between vortices, or whirlpools, and tracking changes in water flow left by prey—even without the aid of vision.
Along Their Sides
To explore how fish exploit flow information, the research team focused on a fish’s “lateral line”—a system of sensory organs known to detect both movement and vibration in the water that surrounds them—with particular consideration to the line’s sensory-laden canals that open to the environment through a series of pores.
