THE DYNAMICS OF PARENT OFFSPRING RELATIONSHIPS IN MAMMALS

Evolutionary theories about parent-offspring relationships have predic ted that young will aggressively demand food and care from their paren ts at the time of weaning when the parents should, in their own intere sts, reserve their efforts for future offspring. Detailed studies of t he behavioural development of mammals have given only limited support for these expectations. Often the mother is more amenable to the needs of her offspring than evolutionary theory predicts, and often offspri ng are sensitive to the state of their mother, tuning the pattern of t heir own development accordingly. Such aggression as is seen between m other and offspring tends to occur at stages other than weaning. The m ismatch between theory and evidence may arise because a mother needs t o monitor her offspring's state as well as her own and respond appropr iately in order to maximize her own reproductive success. Similarly, a n offspring needs to monitor its mother and prepare for the world in w hich it will grow up, in order to maximize its chances of surviving to breed.