Socially induced infertility: familial effects on reproductive development of female Mongolian gerbils

We examined social influences on age at first reproduction in female members of 240 litters of Mongolian gerbils, Meriones unguiculatus. The results indicated that: (1) sisters inhibit one another's reproductive development, although this mutual inhibition is more strongly expressed in the presence than in the absence of an older, reproductively active female, (2) either sexual incompatibility develops between male gerbils and females that they …