How Fish on Treadmills Could Improve Human Hearing

(Inside Science TV) -- No matter how deep they go or how fast they move, learning how fish navigate through their watery world may help scientists fight disease and create new technology.

James Liao, a marine biologist at the University of Florida in St. Augustine, said, “We’re trying to understand the physics of how these animals can move so efficiently through the water. In particular, how we can study fish to understand human health and diseases.”

It’s the study of biomimetics. “Biomimetics is actually mimicking biology in order to gain insight into how things work,” described Liao.

To do this, Liao is studying the movement of trout and zebrafish. He and his team study them in a flow tank, which is like a treadmill for fish.

Inside the tank, water can be pushed through fast or slow, and carefully placed cylinders create turbulence. While a high-speed video camera records, a laser is shone through the water and bounces off a mirror underneath the tank, which allows the researchers to see the invisible currents of the water.

“We take the images from the video camera and we can reconstruct the motions of the water. So it’s a way to visualize clear water,” Liao said.

When the fish move through varying degrees of turbulence, they produce swirls of water called eddies.

“It turns out a fish will learn how to shut down all of its muscles and surf on the eddies created behind the cylinder,” he said.

The fish senses the turbulence by using a sixth sense called the lateral line system.

“It’s made up of a clusters of hair cells which can detect the water flow across the skin of the animal,” said Liao.

The hair cells that cover the zebrafish are almost identical to the hair cells in a human’s inner ear.

“By understanding how fish swim we can actually better understand how people can hear better,” said Liao.

Get Inside The Science:

Biomechanics And Neurobiology Of Fish Locomotion

James Liao , University of Florida