Natural variations in postpartum maternal care in inbred and outbred mice.

The role of maternal care in mediating variation in offspring phenotype has been examined in the rat and demonstrates that mother-infant interactions are critical for inducing long-term changes in behavior. Though phenotypic differences between mice strains are often attributed to genetic factors, the influence of early maternal environment has not been extensively explored. To understand maternal influence on phenotype in mice, we must first explore the nature of differences in behavior.