This paper aims to compare cognitive development in humans and chimpanzees to illuminate the evolutionary origins of human cognition. Comparison of morphological data and life history strongly highlights the common features of all primate species, including humans. The human mother-infant relationship is characterized by the physical separation of…

Responds to Maccoby's and Hinde's commentaries on the Belsky, et al. article in this issue. Highlights several points of concurrence and disagreement. Draws attention to the potential benefits of asking questions about proximal and ultimate causation simultaneously and, thus, the need for child developmentalists to think about both the how and why…