Pii: S0149-7634(00)00036-1

The reproductive strategy of many mammalian species that give birth to altricial young involves intense and prolonged care of their offspring. In most cases, the mother provides all nurturance, but in some cases fathers, older siblings, or unrelated conspeci®cs participate in parental care. The display of these behaviors by animals other than mothers is affected by numerous factors, including their sex. We herein review the literature on similarities and/or differences between male and female laboratory rodents (rats, mice, voles, gerbils, and hamsters) in their parental responsiveness and discuss how the parental behavior of males and females is in ̄uenced by hormones, developmental processes, and prior social experiences. Understanding the mechanisms that generate sex differences in the parental responsiveness of rodents may indicate how similar sex differences in parental care are generated in other mammals. q 2000 Elsevier Science Ltd. All rights reserved.