Vibrating Tree Frogs

This Species Has Developed an Unusual Way to Communicate

by Pallav Regmi, age 12

How animals communicate has long been of interest to many scientists.  Animals are known to use acoustic and visual signals, as well as physical interactions, as methods of communication.  However, scientists have learned that some animals use a different method of communication: vibration.  Researchers recently discovered that male red-eyed tree frogs communicate using vibration.  These frogs shake plant branches very quickly, sending vibrations to other frogs on the tree.  The frog vibrates by contracting and extending his limbs 12 times per second.  If a male frog feels that another male frog is trespassing on his territory, he will start to send a stronger, more menacing vibration to ward off the invader.

“They’re essentially doing push-ups with their rear legs, but really fast ones,” says Michael Caldwell, a post-doctorate at the Smithsonian Tropical Research Institute.

Vibration used as a sign of male aggression is commonly displayed during the frog’s mating season.  Frogs might also send each other acoustic signals or even start to fight until the weaker one departs.
While it is true that monkeys also shake branches, scientists believe that they do so only as a visual form of communication.  Insects also send vibrations as a form of communication. But these frogs are the first vertebrates noted by scientists to use vibration in this way.

[Sources: The New York Times; Ranger Rick]