You might not hear it, but rodents are known to speak to each other in voices so high-pitched that human ears can’t pick them up. Now scientists have found that these vocalizations might have a second purpose – they help them smell better.
It turns out that the squeaks of cartoon mice are not far from the truth. For decades scientists have recorded rodents vocalizing at ultrasonic frequencies, which is believed to be a form of communication and might help them find mates. It might even be a kind of laugh, since they also do it when researchers tickle them, according to one of the most endearing studies of recent years.
In a new study, scientists from the University at Buffalo have identified another potential, unexpected benefit of rodents’ ultrasound pulses. The animals could use these sounds to stir up particles in the air around them, which they can quickly inhale to boost their already strong sense of smell.
“This phenomenon has never been observed before, or I believe even suspected, in any animal,” says Eduardo Mercado III, co-author of the study. “They’re creating new pathways of information by manipulating their environment and controlling the molecular interactions of particles around them.”
The researchers were first inspired to investigate the idea by previous studies into how rodents navigate their environment. It was found that the animals would usually sniff the air immediately after making each ultrasound vocalization (USV).
“That could be a coincidence, or it might suggest the two are functionally related,” says Mercado. “I knew that techniques for using ultrasound to manipulate particles are used in the field of vibroacoustics and thought immediately that might also work for animals.”
Vibroacoustics is a field of study where ultrasound vibrations are used to create clusters of particles in the air. It’s possible, the team hypothesizes, that mice and rats are doing the same thing, creating clusters of odor molecules that can be picked up more easily by their powerful noses. That could include pheromones left by friends, rivals, and potential mates.
While the researchers lay out the case for this concept, it hasn’t yet been experimentally confirmed. But it’s an intriguing idea that could reveal new insights into animal behavior and abilities that might be hiding right under our noses, as it were.
The research was published in the journal Neuroscience & Biobehavioral Reviews.
Source: University at Buffalo