Horse owners know that a low-pitched nicker indicates friendly recognition, and an anxious call is a sign of stress. Now researchers are looking for a scientific link between the acoustic properties of equine communications and their possible meanings.

David G. Browning, MS, of the University of Rhode Island’s Department of Physics, and Peter M. Scheifele, PhD, MD, from the Animal Science Department of the University of Connecticut, have teamed up to translate familiar equine vocalizations through a study dubbed the Equine Vocalization Project.

“We found that by its acoustic structure–its wide bandwidth and varying frequency–during the vocalization, the whinny has the potential to be a means of expressing emotion,” said Browning. “Now the key question is whether a horse does this, and if so under what conditions.”

The Equine Vocalization Project is now trying to ascertain whether horses actually use their vocal abilities to express emotion–whether the whinny emitted upon seeing a pasture mate is significantly different acoustically than the whinny emitted upon seeing a strange horse