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Lodestars and Old Loves: Reconsidering Classic Developmental Ideas for Today's World

This double issue of Research in Human Development contains seven articles that reconsider some classic ideas or works related to human development and the life course—lodestars that once guided our fields or old loves that first attracted us to our subject matter. The authors have been asked to playfully explore how those ideas or works might be extended or reformed in light of contemporary life. To this end, the authors reflect on new theories that might be crafted, questions that might be asked, hypotheses that might be tested, methods that might be used, or data that might be gathered. The articles treat the fields of behavior genetics, motivation, attachment, and social ecology as well as the concept of generations, the changing landscape of adult life, and controversies surrounding the institutionalization and deinstitutionalization of the life course. The first article, by Loehlin (this issue), is “The Strange Case of c2 =0: What Does It Imply for Views of Human Development?.” Loehlin points to a large body of evidence that leads to a rather shocking conclusion: For many behavioral traits, the effect that a shared a family environment during childhood (c2) has on siblings early in life is substantial, but during adulthood, that value approaches zero. The story of c2 =0 is a complicated one. However, there can be no question that the plummeting of c2 in adulthood poses a serious challenge to developmental scientists, for it calls into question pervasive assumptions, in both science and society, that early family factors have powerful and enduring effects on personality and abilities.