[[{“type”:“media”,“view_mode”:“media_large”,“fid”:null,“attributes”:{“class”:“media-image alignright size-full wp-image-1606”,“typeof”:“foaf:Image”,“style”:“”,“width”:“100”,“height”:“100”,“alt”:“New York Times”}}]]A Dartmouth professor and his colleagues have discovered that tarsiers, tiny primates found in southeast Asia, communicate with calls that are inaudible to humans.

Prior to the discovery, scientists were perplexed when the animals would open and close their mouths, as if yawning. Now, they realize the tarsiers were emitting ultrasonic shrieks, too high-pitched for humans to hear.

Associate Professor of Anthropology Nathaniel Dominy was part of the team that made the discovery. “Some primates have calls that contain small components of ultrasound,” he told The New York Times. “But tarsiers produce calls that are entirely in the ultrasound.”

Read the full story, published 2/9/12 by The New York Times.