Rats use ultrasound to boost their fine sense of smell for dynamic social interactions

Amazing stuff!

"... 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 ... 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. ...

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). ..."

"... Vibroacoustics, or artificially produced ultrasonic vibrations, cause airborne particles to cluster, leading Mercado to suggest that rodents are using USVs to create odor clusters enhancing the reception of pheromones (chemical signals), thus making it easier for the vocalizer to detect and identify friends, strangers, and competitors. ..."

From the highlights and abstract:

"Highlights

• Rodent vocalizations could contribute to a unique mode of active olfactory sensing.

• Ultrasonic vocalizations may affect how rodents smell by clustering inhaled odorants.

• Coordinating sniffing with sound production might enhance reception of pheromones.

Abstract

Chemosensation via olfaction is a critical process underlying social interactions in many different species. Past studies of olfaction in mammals often have focused on its mechanisms in isolation from other systems, limiting the generalizability of findings from olfactory research to perceptual processes in other modalities. Studies of chemical communication, in particular, have progressed independently of research on vocal behavior and acoustic communication. Those bioacousticians who have considered how sound production and reception might interact with olfaction often portray odors as cues to the kinds of vocalizations that might be functionally useful. In the olfaction literature, vocalizations are rarely mentioned. Here, we propose that ultrasonic vocalizations may affect what rodents smell by altering the deposition of inhaled particles and that rodents coordinate active sniffing with sound production specifically to enhance reception of pheromones. In this scenario, rodent vocalizations may contribute to a unique mode of active olfactory sensing, in addition to whatever roles they serve as social signals. Consideration of this hypothesis highlights the perceptual advantages that parallel coordination of multiple sensorimotor processes may provide to individuals exploring novel situations and environments, especially those involving dynamic social interactions."

Rats use ultrasound to boost their sense of smell, suggests new study

‘Use the force,’ Mickey: Study suggests that ‘Jedi’ rodents remotely move matter using sound to enhance their sense of smell (original news release) "It’s so far off the scale of what we know … it almost seems like magic,’ says University at Buffalo researcher Eduardo Mercado III"

Do rodents smell with sound? (no public access)