Gender differences in variability in intellectual abilities: A cross-cultural perspective

A cross-cultural quantitative review of contemporary findings of gender differences in variability in verbal, mathematical, and spatial abilities was conducted to assess the generalizability of U.S. findings that (a) males are more variable than females in mathematical and spatial abilities, and (b) the sexes are equally variable in verbal ability. No consistent gender differences (variance ratios) were found across countries in any of the three broad ability domains. Instead, males were more variable than females in some nations and females were more variable than males in other nations. Thus, the well-established U.S. findings of consistently greater male variability in mathematical and spatial abilities were not invariant across cultures and nations.I would like to thank Robert Linn for providing me with the British norms for the Differential Aptitude Tests and Julian Stanley for his comments on a draft of this article.     

The development of referential offering in the first year

The ontogeny of referential offers was examined in a longitudinal, within dyad case study of two mother–infant pairs. A combination of microanalytic and qualitative methodologies was employed in describing the functions and morphology of this gesture, as well as its temporal and sequential organization with a number of infant and maternal behaviours. Offers were found to emerge from repetitive, exploratory play routines that provide infants with alternative visual perspectives on objects, and were facilitated by mothers' support of infants' immature attentional, motoric and arousal regulation capacities. Offers were observed to co. occur with maternal behaviours that direct and maintain infants' attention to objects. Our observations suggest that offers are transformed through guided interactions into conventional communicative gestures. Offering arises as mothers become part of the infants' exploratory play routines, gradually changing the function of the behaviour of the infants. These observations are consistent with dynamic systems models of development.