Mating behavior differences in monogamous and polygamous sympatric closely related species Mus musculus and Mus spicilegus and their role in behavioral precopulatory isolation

Closely related species with different mating system may be the most suitable model taxa for studies aimed to highlight the cause formation of species-specific peculiarities of sexual behavior and behavioral mechanisms of precopulatory isolation. The current study aimed to clarify the role of the mating system and lifestyle, including ecology features, in patterning of behavioral activities during mating, as well as the role of behavioral patterns in the precopulatory isolation of closely related Mus taxa. Test subjects were closely related sympatric species: polygynous/promiscuous M. musculus and presumably monogamous M. spicilegus, reproductively isolated in nature. Dyadic encounters of male and receptive female were conducted in clear chambers and the behavior was recorded by means of video camera. Sexual behavior, culminating in ejaculation, was observed in conspecific dyadic encounters only; it occurred more frequently and with longer duration in males of M. spicilegus, than in males of M. musculus. In conspecific encounters, males of M. spicilegus exhibited a higher level of affiliative behavior than females. In both species total frequency and duration of aggressive behavior was higher in females compared to males. In heterospecific dyadic encounters the behavioral pattern of males and females was strictly different from those in conspecific encounters, and the elements of aggressive behavior prevailed. We demonstrated that not only the pattern of sexual behavior is important for reproductive isolation, but also all types of behavioral interactions preceded copulation. In Mus species different stereotypes of mating behavior during the encounter of potential sexual partners can prevent successful copulation and may be associated with mating system. How to cite this article: Ambaryan A.V., Voznessenskaya V.V., Kotenkova E.V. 2019. Mating behavior differences in monogamous and polygamous sympatric closely related species Mus musculus and Mus spicilegus and their role in behavioral precopulatory isolation // Russian J. Theriol. Vol.18. No.2. P.67–79. doi: 10.15298/rusjtheriol.18.2.01