Journal of Comparative Psychology 19S4,Vol 89. No 4,414-420 Copyright 1984 by the American Psychological Association, Inc Urinary Chemosignals From Mice (Mus musculus): Acceleration and Delay of Puberty in Related and Unrelated Young Females Lee C. Drickamer Biology Department Williams College A series of five experiments was carried out to determine the possible differ- ential effects that urinary chemosignals from genetically related and unrelated donors have on puberty onset in female mice. The first four experiments, with a laboratory mouse strain, demonstrated no differential acceleration or delay of sexual maturation, with respect to a close genetic relation between donors and recipients, due to the chemosignals from estrous, diestrous, pregnant, or lactating females or grouped females. In the last experiment, wild stock Mus were used; all of the results were comparable to those found in laboratory stocks. There were no instances of differential acceleration or delay based on close genetic relatedness of donors and recipients. The results conform with a general hypothesis that the urinary chemosignals in mice communicate infor- mation about the adequacy of reproductive conditions to conspecifics. Four urinary chemosignals from male and female mice affect the age of puberty in young female conspecifics; puberty is accelerated by urine from male mice (Colby & Vandenbergh, 1974; Drickamer & Mur- phy, 1978; Vandenbergh, 1969) by urine from pregnant or lactating females (Drick- amer & Hoover, 1979), and by urine from estrous but not diestrous females (Dricka- mer, 1982b), and puberty is delayed by urine from grouped female mice (Dricka- mer, 1974, 1977). These chemosignal ef- fects, investigated initially with laboratory strains of mice, have now been confirmed with wild mouse stocks in the laboratory (Drickamer, 1979, in press) and for wild mice living in nature (Massey & Vanden- bergh, 1980, 1981). These chemosignal phenomena have been tested for hormone influences (Drick- amer & Mclntosh, 1980; Drickamer, Mc- Intosh, & Rose, 1978; Drickamer & Mur- phy, 1978; Vandenbergh, 1969), for the tim- ing and duration of urine treatment given to young females (Colby & Vandenbergh, 1974; Drickamer, 1977), and with regard to This research was supported in part by National Institutes of Health Grant HD-08585. Requests for reprints should be sent to Lee C. Drickamer, Biology Department, Williams College, Williamstown, Massachusetts 01267. the ages at which the mice are treated (Colby & Vandenbergh, 1974; Drickamer, 1977). Also, for several of the effects, tests have been conducted regarding the genetic relatedness of mice that provide the urine and the females treated with the urine. There is no acceleration of puberty when young females are treated with urine from the father or an older full-sib brother, rel- ative to treatment with urine from an un- related male (Drickamer, 1983). Also, there is no difference in the delay of sexual mat- uration of young females when they are grouped with sibs and when they are grouped with non-sibs (Drickamer, 1982b). Additional questions pertaining to ge- netic relations between donors and recipi- ents include the following: (a) Does urine from lactating dams differentially acceler- ate sexual development in their own female progeny relative to females not their own? (b) Does urine from pregnant females effect an earlier puberty in the dam's own daugh- ters relative to unrelated young females? (c) Does the urine from grouped females differ in its puberty-delaying influence de- pending upon either the genetic relatedness of the donors or the relation between do- nor(s) and young test females? (d) Does the urine from estrous females differentially accelerate sexual development if the young 414