The influence of familiarity, age, experience and female mate choice on pregnancies in captive grey mouse lemurs

Abstract

AbstractConceptions in mammals may depend on a variety of factors including mate familiarity, age, sociosexual experience and female mate choice. We tested predictions for the effects of these factors on pregnancies in a captive colony of grey mouse lemurs (Microcebus murinus). The succession of oestrous cycles and pregnancies was analysed for a total of 26 different females that were housed together with 33 different males over a total of 124 oestrous cycles between 1995 and 2001. In addition, sexual behaviours were recorded and analysed over 13 oestrous cycles of 9 different females. An effect of mate familiarity on pregnancies could be detected by a frequent delay of pregnancies to the second cycle of the season (66.7% of the possible cases). Female age influenced pregnancies as the 2-3-year old females were less likely to become pregnant than females of other age classes. This reduced rate of pregnancies, however, was probably due to the lack of previous sociosexual experience with males. Females that have not been housed with males within their first reproductive season, needed one or two years of sociosexual experience before their first successful impregnation. These findings are discussed as a side effect of the ontogenetic development of female dominance. Female mate choice could be deduced from the succession of pregnancies and the strong responsibility of the females for the termination of matings.