Ultrasonic communication in rats

Written by Thomas Hesselberg

Wednesday, 02 January 2008

Rats seem to use ultrasound as a form of communication. Photo courtesy of US National Park Service.
Rats are (in)famous for their versatility and their ability to survive and thrive under many different conditions. An important reason for this is the rats advanced social behaviour and their ability to effectively communicate with conspecifics. Rats emit two different kinds of signals – low frequency calls in the 22 kHz range and high frequency 50 kHz calls. The low frequency calls are used as alarm cries and for instance emitted during exposure to predators, during male-male aggression and during social isolation. Thus they have a clear communicative aim. The high frequency ultrasonic calls, in contrast, are used during play, mating and food consumption. The communicative role of ultrasonic calls is not clear. However, now Markus Wöhr and Rainer Schwarting from the University of Magdeburg in Germany have shown that ultrasonic signals serve a communicative purpose.

The German scientists conducted behavioural experiments on juvenile and adult male rats running in a radial maze. The rats were subjected to playback of both natural and artificial sound and their subsequent behaviour was recorded with a video camera. The results showed that locomotor activity of the rats increased in response to 50 kHz sound in comparison to 22 kHz calls and general noise.

The rats were also generally approaching the ultrasonic sound source both when artificial and when natural playback sounds were used. Interestingly, juvenile rats show a higher response than adult rats, which demonstrates that ultrasonic communication is used in a non-sexual context. The results show that ultrasonic calls induce approach behaviour in male rats and thus suggest that they serve a communicative purpose to establish or keep in contact with conspecifics.

Source:
Wöhr, M. and Schwarting, R. K. W. (2007). Ultrasonic Communication in Rats: Can Playback of 50-kHz Calls Induce Approach Behavior? PLoS One 2(12): e1365.doi:10.1371/ journal.pone.0001365

Tag it:

Add as favourites (26) |

Quote this article on your site | Views: 1327 | E-mail

Be first to comment this article

Only registered users can write comments.
Please login or register.