Olfactory responses of neotropical short-tailed singing mice, Scotinomys teguina, to odors of the mid-ventral sebaceous gland: discrimination of conspecifics, gender, and female reproductive condition.

We examined the olfactory communication of the Neotropical short-tailed singing mouse, Scotinomys teguina, by investigating whether S. teguina responded to odors produced by the mid-ventral sebaceous gland of conspecifics. Females spent significantly more time investigating male odor than an odorless stimulus or a female odor. Males spent significantly more time investigating female odor than an odorless stimulus, but not that of a male odor. This latter result does not seem to be explained by differences in age or sexual experience of test subjects, but may be influenced by reproductive condition of the female odor donor. Male S. teguina spent significantly more time (1) investigating and (2) in total proximity to odors of estrous than non-estrous females. Males spent more time (1) investigating and (2) in total proximity to odors of males than non-estrous females. Finally, given the choice between odor of males vs proestrous females, males showed no preference. Thus, the mid-ventral gland in S. teguina seems to convey information about conspecifics, sex, and female reproductive condition. Male odor, compared with proestrous female odor, is equally interesting to males, suggesting that the gland also plays an important role in male-male communication. Sexual dimorphism in the size of the gland and in the amount of secretion produced by the gland may be related to either male-male competition or female choice.