Developmental science refers to afresh synthesis that has been generated to guide research in the social, psychological, and biobehavioral disciplines. It describes a general orientation for linking concepts and findings of hitherto disparate areas of developmental inquiry, and it emphasizes the dynamic interplay of processes across time frames, levels of analysis, and contexts. Time and timing are central to this perspective. The time frames employed are relative to the lifetime of the phenomena to be understood. Units of focus may be as short as milliseconds, seconds, and minutes, or as long as years, decades, and millennia. In this perspective, the phenomena of individual functioning are viewed at multiple levels – from the subsystems of genetics, neurobiology, and hormones to those of families, social networks, communities, and cultures.

We believe that recognizing the complexity of development is the first step toward understanding its coherence and simplicity. In this perspective, patterns of adaptation represent interactions across levels within and without the person. Because the relative weights of these contributors to behavior vary across ontogeny and across domains, longitudinal analyses have particular value in understanding how they are coalesced over development. The pathways of development are relative to time and place; they contribute to – and reflect – temporal changes in culture and society. Developmental investigation focuses attention on the ontogenies of both embryos and ancestors, and on the process by which pathways may be repeated or redirected across successive generations.