Bat wings sport a unique touch-receptor design, researchers reported Thursday in the journal Cell Reports. Tiny sensory cells associated with fine hairs on the bat wing likely enable the animals to change the shape of their wings in a split second, granting them impressive midair maneuverability.
After rendering bat wings temporarily hairless with an over-the-counter depilatory cream, researchers led by Cynthia Moss at Johns Hopkins University measured the bats' flight behaviors. The scientists found that without wing hair, bats did not slow as quickly when they approached objects. Their midair turns were also less tight. Neurological studies revealed that bat brain cells responded when the hairs were stimulated with air puffs or light touch.
To learn more, Moss and scientists in her lab teamed up with Columbia University biologist Ellen Lumpkin, who specializes in touch receptors. The scientists were able to identify sensory cells, called Merkel cells, which are dedicated to fine touch in the bat wing. These Merkel cells were closely associated with the fine hairs of the wing; some 47 percent of wing hairs had a Merkel cell next door to the follicle, the researchers found.
The hairs "serve as a lever, and when they move, that activates the receptor," Moss said. Other sensory cells, called lanceolate endings, were also found near hairs. Together, Moss said, these cells provide bats with immediate information about airflow over the wing.
The findings might also inspire human engineering. "There are potential applications for aerial vehicles to become more maneuverable, drawing on some of the biological principles that are illustrated in the bat," Moss said.