Recognition of individuals is essential for social interactions in many species, including mice. This recognition can be mediated by chemical signals, such as pheromones, as well as by visual, auditory, and tactile cues.
In a new study, researchers at the University of Warwick have investigated the role of chemical signals in individual recognition in mice. The researchers found that mice are able to recognise each other based on their urine chemical profiles, and that this recognition is mediated by the vomeronasal organ (VNO).
The VNO, located at the base of the nose, is a specialised sensory organ that detects pheromones and other chemical signals. Previous research has shown that the VNO is important for many social behaviours in mice, including aggression, mating, and parenting.
In the current study, the researchers conducted a series of experiments to test the role of the VNO in individual recognition. First, they collected urine samples from individual mice and then presented these samples to other mice. They found that mice were able to discriminate between the urine samples of familiar and unfamiliar mice, suggesting that they were able to recognise each other based on their urine chemical profiles.
Next, the researchers removed the VNO from some of the mice and then tested their ability to recognise each other. They found that mice without a VNO were not able to discriminate between the urine samples of familiar and unfamiliar mice, suggesting that the VNO is necessary for individual recognition.
Finally, the researchers investigated the role of specific chemical compounds in individual recognition. They found that mice were able to recognise each other based on the presence of a specific pheromone, called 2-sec-butyl-4,5-dihydrothiazole (SBT). SBT is produced by the preputial glands of male mice and is thought to play a role in social interactions.
The findings of this study suggest that chemical signals, particularly those detected by the VNO, play a key role in individual recognition in mice. This recognition is important for many social behaviours, including aggression, mating, and parenting.
