Abstract
Human life history (LH) variation stems from developmental phenotypic responses to childhood environments. As with other psychological constructs, LH variation can be assessed by asking questions that are statistically linked to the underlying LH traits. This study introduces the fast-slow scale (FSS), a 35-item questionnaire designed to measure fast-slow LH strategies in adults. The FSS asks questions about trade-offs involving energy, resources, and time, as well as trade-off questions concerning the life domains of sexuality, sociality, and cognitive style. Two validation studies based on community samples totaling 1,491 participants support the internal structural and the external nomological validity of the FSS.