Postnatal maternal care predicts divergent weaning strategies and the development of social behavior.

Maternal care experienced during postnatal development predicts long-term neurobiological and behavioral outcomes. However, the cascade of behavioral changes that emerge in response to maternal care has not been elucidated. In the current study, we examine naturally occurring variation in postnatal licking/grooming (LG) in C57BL/6J mice to determine its impact on preweaning maternal and pup behavior, the weaning process, the pace of developmental change, the emergence of social behavior, and indices of anxiety-like behavior in adulthood. Our analyses indicate that lower postnatal LG is associated with truncated and more infrequent maternal behavior during the preweaning period. Moreover, compared to High LG dams, Low LG dams are observed to actively wean their offspring sooner and have offspring that play more frequently. The heightened pace of developmental change observed in offspring of Low LG dams suggests a more rapid transition to behavioral and nutritional independence, which could have implications for future reproductive strategies.