ABSTRACT

Non-parental care in the form of daycare, practiced in industrialized societies, is an evolutionary novelty. Segregating children by age is new. Throughout most of human history, people lived in small foraging groups and children rarely had playmates of the same age. Socialization involved interacting with people of all ages, from infants to grandparents (Konner, 2005). In foraging groups and village-based societies today, children play in multi-age playgroups (Hewlett and Lamb, 2005) and may be watched over by various carers, including older sisters and grandmothers (Hrdy, 2005).