The development of social behaviour is a continuous process occurring through­out the lifespan: from infancy to senescence. It is, however, during the earlier phases of lifespan development that the roots of social behaviour are established through both biological and environmental factors. Biological and environmental factors are often pitted against one another using a nature (innate biology) versus nurture (learned environment) framework. Over the years of research, however, a two-camp approach to understanding social development has proven to be sim­plistic and misleading. There is a bi-directional interaction between the effects of nature and nurture...