Flexible skin folds help elephants stretch their trunks

Today’s Video of the Day from Georgia Tech describes how skin plays an important role in giving elephant trunks flexibility. The researchers found that the skin on an elephant’s trunk does not stretch uniformly. 

“When people extend their tongue – a muscle-filled, boneless tissue similar in composition to an elephant’s trunk – it stretches uniformly. We expected the same when we challenged an elephant to reach for food,” said study lead aptly Andrew Schulz.

“But when we looked at our high-speed camera footage and plotted the trunk’s movements, we were surprised. The top and bottom weren’t the same at all.”

When an elephant is stretching to reach food or other objects, the skin folds on the dorsal surface prove to be more stretchy than the wrinkled ventral skin – allowing the trunk to extend further. 

“Flexible skin folds are the elephant’s innovation,” said Professor  David Hu. “They protect the dorsal section and make it easier for the elephant to reach downward, the most common gripping style when picking up items.”

In addition to gaining a better understanding of elephants, Schulz sees applications for the knowledge in the field of soft robotics.

“Soft robotics created with biologically inspired design are always based on muscle movement. If they were wrapped with a protective skin, like an elephant’s muscle-filled trunk, the machines could apply larger forces,” said Schulz. “Last year we learned that a trunk is a multi-purpose, muscular hydrostat. Now we know that skin is another tool at its disposal.”

Video Credit: Georgia Tech/Zoo Atlanta

–—

By Chrissy Sexton, Earth.com Editor

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.