The now‐classic article “What Is Temperament? Four Approaches” by H. H. Goldsmith et al. (1987) brought together originators of four prominent temperament theories—Rothbart, Thomas and Chess, Buss and Plomin, and Goldsmith—to address foundational questions about the nature of temperament. This article reviews what has been learned about the nature of temperament in the intervening 25 years, It begins with an updating of the 1987 consensus definition of temperament that integrates more complex current findings. Next, 4 “progeny” trained in the original temperament traditions assess contributions of their respective approaches. The article then poses essential questions for the next generation of research on the fundamentals of temperament, including its structure, links with personality traits, interaction with context, and change and continuity over time.

Most temperament theories presume a biological basis to those behavioral tendencies thought to be temperamental in origin. Behavioral genetic methods can be used to test this assumption. Twin and adoption studies suggest that individual differences in infant and child temperament are genetically influenced. However, behavioral genetics has much more to offer to the study of temperament than simple heritability estimates. The present paper describes some recent findings from behavioral genetics research in temperament that go well beyond the basic nature-nurture question. These findings include the importance of nonshared environmental influences on temperament, genetic continuity and environmental change during development, links between temperament and behavior problems, and harnessing the power of molecular genetics to identify specific genes responsible for genetic influence on early temperament. Keywords genetic; shared environment; nonshared environment; heritability; temperament Although there are many different theories of child temperament, most agree that temperament refers to stable, early appearing individual differences in behavioral tendencies that have a constitutional basis1. Soon after birth, children show a great deal of variation in those behavioral dimensions considered to be temperamental (e.g., emotionality, activity level, attention/persistence, sociability, reactivity, etc.). For example, some children cry easily and intensely whereas others are more easy going; some are highly active and always on the go where others are more sedentary; some attend and persist in tasks for long periods of time where others' attention wanders quickly. It is these individual differences and the variations in between that are of interest to behavioral geneticists. That is, we are interested in understanding why children differ in their temperaments. Temperament theories suggest that such individual differences have a biological or constitutional foundation. This is an empirical question that can be answered using behavioral genetic methods.After a brief review of behavioral genetic methodology, this paper will examine research exploring the etiology of individual differences in infant and child temperament. Behavioral genetics research, however, has much more to offer the study of temperament than estimates of genetic influence. To that end, this paper will also examine the nature of environmental influences on temperament; the etiology of continuity and change in temperament; links between temperament and behavior problems; and the merging of behavioral and molecular genetic techniques to identify specific genes that affect temperament.

In response to criticisms of the Conflict Tactics Scales, Straus revised the original scale to include sexual aggression and injury. The purpose of the present study was to use this new scale to replicate and expand existing knowledge of psychological, physical, and sexual aggression in dating relationships. Four-hundred-eighty-one college students completed the Revised Conflict Tactics Scales. As expected, females reported perpetrating more psychological aggression than males; there were no gender differences in reported physical aggression; and psychological and physical aggression tended to co-occur. Contrary to previous research, there were no gender differences in injuries. As expected, males reported perpetrating more sexual coercion than females; however, females also reported perpetrating sexual aggression, and there were no gender differences in reported victimization. For males, sexual coercion perpetration (not victimization) was related to the perpetration and victimization of physical and psychological aggression. For females, both sexual coercion perpetration and victimization were related to the perpetration and victimization of psychological aggression and victimization from physical aggression, but not to physical aggression perpetration.

Environmental factors shared by co-twins affect BMI in childhood, but little evidence for their contribution was found in late adolescence. Our results suggest that genetic factors play a major role in the variation of BMI in adolescence among populations of different ethnicities exposed to different environmental factors related to obesity.

Previous research in the Swedish Adoption/Twin Study of Aging (SATSA) has found genetic influences on life events (R. Plomin, P. Lichtenstein, N.L. Pedersen, G.E. McClearn, & J.R. Nesselroade, 1990). The present study extends this finding by examining sex differences in genetic and environmental contributions to life events and by examining personality as a mediator of genetic influences on life events in SATSA. Analyses were based on 320 twin pairs, including identical and fraternal twins reared together and apart (mean age = 58.6 years). Controllable, desirable, and undesirable life events were revealed significant genetic variance for women. There was no significant genetic variance for either sex for uncontrollable events. Multivariate analyses of personality (as indexed by Neuroticism, Extraversion, and Openness to Experience) and life events suggest that all of the genetic variance on controllable, desirable, and undesirable life events for women is common to personality. Thus, in this sample of older adult women, genetic influences on life events appear to be entirely mediated by personality.