Examines the interplay between genes and environment and argues that the development of much individual variation can be explained in terms of relatively simple forms of underlying regulation. Looks at "sensitive periods," during which variation is produced by experience received at a particular age. Includes a discussion of the…

Described is an ongoing study of monozygotic and dizygotic twins, separated in infancy and reared apart. Discussed are the procedures and results of this study with interpretations of the results. The effects of parenting, education, and other interventions are considered. (CW)

Reports on a study of the determinism-free will debate presented in 15 textbooks published between 1956-1965 and 38 texts published between 1983-1992. Finds that most textbooks still favor a deterministic position. Issues a call to sociology teachers to reflect carefully about the way the choice debate is depicted. (CFR)