Featured Research

from universities, journals, and other organizations

Bats Use Touch Receptors On Wings To Fly, Catch Prey, Study Finds

Date:
December 15, 2005
Source:
Ohio University
Summary:
Bats have an “ear” for flying in the dark because of a remarkable auditory talent that allows them to determine their physical environment by listening to echoes. But an Ohio University neurobiology professor says bats have a “feel” for it, too. John Zook’s studies of bat flight suggest that touch-sensitive receptors on bats’ wings help them maintain altitude and catch insects in midair. His preliminary findings revive part of a long-forgotten theory that bats use their sense of touch for nighttime navigation and hunting.

Bat wings show a series of raised domes with touch receptors.
Credit: Photo by: John Zook

Bats have an “ear” for flying in the dark because of a remarkable auditory talent that allows them to determine their physical environment by listening to echoes. But an Ohio University neurobiology professor says bats have a “feel” for it, too.

John Zook’s studies of bat flight suggest that touch-sensitive receptors on bats’ wings help them maintain altitude and catch insects in midair. His preliminary findings, presented at the recent Society for Neuroscience meeting, revive part of a long-forgotten theory that bats use their sense of touch for nighttime navigation and hunting.

The theory that bats fly by feel was first proposed in the 1780s by French biologist Georges Cuvier, but faded in the 1930s when researchers discovered echolocation, a kind of biological sonar found in bats, dolphins and a few other animals. Bats use echolocation to identify and navigate their environment by emitting calls and listening to the echoes that return from various objects.

Zook believes the touch-sensitive receptors on bats’ wings work in conjunction with echolocation to make bats better, more accurate nocturnal hunters. Echolocation helps bats detect their surroundings, while the touch-sensitive receptors help them maintain their flight path and snag their prey.

Touch receptors take the form of tiny bumps, or raised domes, along the surface of bats’ wings. The domes contain Merkel cells, a type of “touch” cell common in bumps on the skin of most mammals, including humans. Bat touch domes are different, however, because they feature a tiny hair poking out of the center.

When Zook recorded the electrical activity of the Merkel cells, he found they were sensitive to air flowing across the wing. These cells were most active when airflow – particularly turbulent airflow – stimulates the hair. When a bat’s wing isn’t properly angled or curved during flight, air passing next to the wing can become turbulent. Merkel cells help bats stay aerodynamically sound by alerting them when their wing position or curve is incorrect, preventing the creatures from stalling in midair.

“It’s like a sail or a plane. When you change the curve of a wing a little bit, you get improved lift. But if you curve it too much, the bat – or plane – may suddenly lose lift, hitting a stall point and falling out of the air. These receptor cells give bats constant feedback about their wing positions,” said Zook, who has studied bats for more than 30 years, focusing on echolocation and the bat auditory system. The bat’s sense of touch has been a side interest since the early 1980s.

To test his hypothesis, Zook removed the delicate hairs from bats’ wings with a hair removal cream. Then he let them fly. The bats appeared to fly normally when following a straight path, but when they’d try to take a sharp turn, such as at the corner of a room, they would drop or even jump in altitude, sometimes erratically. When the hairs grew back, the bats resumed making turns normally.

“It was obvious they had trouble maintaining elevation on a turn,” he said. “Without the hairs, the bats were increasing the curve of their wings too much or not enough.”

The bats’ flight behavior also changed based on the area of the wing where the hairs were removed. For example, when Zook removed hairs along the trailing edge of the wings and on the membrane between the legs, the bats were able to fly and turn effectively, but they tended to pitch forward because they couldn’t control their in-flight balance.

Zook’s research also points to the importance of a second type of receptor cell in the membranous part of bats’ wings. Nerve recordings revealed that these receptors respond when the membrane stretches. Zook calls areas on the wing where these stretch-sensitive cells overlap “sweet spots” because they are where bats like to snag their prey. In the lab, Zook shot mealworms covered with flour into the air and recorded how the bats caught them. He could tell from the flour imprints on the wings that the bats caught their prey almost exclusively in the stretch-sensitive sweet spots.


Story Source:

The above story is based on materials provided by Ohio University. Note: Materials may be edited for content and length.


Cite This Page:

Ohio University. "Bats Use Touch Receptors On Wings To Fly, Catch Prey, Study Finds." ScienceDaily. ScienceDaily, 15 December 2005. <www.sciencedaily.com/releases/2005/12/051215231058.htm>.
Ohio University. (2005, December 15). Bats Use Touch Receptors On Wings To Fly, Catch Prey, Study Finds. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2005/12/051215231058.htm
Ohio University. "Bats Use Touch Receptors On Wings To Fly, Catch Prey, Study Finds." ScienceDaily. www.sciencedaily.com/releases/2005/12/051215231058.htm (accessed October 22, 2014).

Share This



More Plants & Animals News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Cadaver Dogs Aid Search for More Victims of Suspected Indiana Serial Killer

Cadaver Dogs Aid Search for More Victims of Suspected Indiana Serial Killer

Reuters - US Online Video (Oct. 21, 2014) Police in Gary, Indiana are using cadaver dogs to search for more victims after a suspected serial killer confessed to killing at least seven women. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
White Lion Cubs Unveiled to the Public

White Lion Cubs Unveiled to the Public

Reuters - Light News Video Online (Oct. 21, 2014) Visitors to Belgrade zoo meet a pair of three-week-old lion cubs for the first time. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
'Cadaver Dog' Sniffs out Human Remains

'Cadaver Dog' Sniffs out Human Remains

AP (Oct. 21, 2014) Where's a body buried? Buster's nose can often tell you. He's a cadaver dog, specially trained to find human remains and increasingly being used by law enforcement and accepted in courts. These dogs are helping solve even decades-old mysteries. (Oct. 21) Video provided by AP
Powered by NewsLook.com
White Lion Cubs Born in Belgrade Zoo

White Lion Cubs Born in Belgrade Zoo

AFP (Oct. 20, 2014) Two white lion cubs, an extremely rare subspecies of the African lion, were recently born at Belgrade Zoo. They are being bottle fed by zoo keepers after they were rejected by their mother after birth. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins