Ultrasonic vocalisations facilitate sexual behaviour of female rats
Abstract
ULTRASONIC vocalisations commonly occur during social interactions among rodents. During mating, adult male and female rats (Rattus norvegicus) emit brief 50-60 kHz ultrasonic calls1; however, the function of these vocalisations is not known. In this study, we demonstrate that these mating calls have a precise function for communication. Specifically, 50-kHz vocalisations elicit sexual activity in female rats. Female rats exhibit a series of solicitation patterns during sexual behaviour, including orientation, darting and ear wiggling. These movements excite the male and enhance the likelihood of mounting, thereby facilitating copulation2-4. (Beach has emphasised the importance of solicitation by the female during mating and has suggested the term `proceptivity' to include the female's behaviour in the initiation and maintenance of copulation.) Although the presence of an intact male is usually a prerequisite for solicitation behaviour, the specific sensory cues which elicit it are not known. Isolated oestrous female rats exposed to ultrasonic vocalisations from a male exhibited a shorter latency to, and higher rate of darting when subsequently placed in a mating situation5. Although the auditory cues primed oestrous females to display increased solicitation behaviour when later confronted with an intact male, there was no indication that these ultrasonic vocalisations had a direct function for communication in the induction of these behaviour patterns. The objective of the present report was to determine if ultrasonic mating calls of rats have a direct function for communication during copulation.
- Publication:
-
Nature
- Pub Date:
- March 1978
- DOI:
- 10.1038/272163a0
- Bibcode:
- 1978Natur.272..163M