The question addressed in the present report is whether the large birth weight differences in dizygotic twin pairs of opposite sex (DZos), especially in 'male first' couples--observed by Blickstein and Weissman (Blickstein I, Weissman A. Birth weight discordancy in male-first and female-first pairs of unlike-sexed twins. Am J Obstet Gynecol 1990;162:661-663) and replicated in the present study-...

Face identity aftereffects suggest that an average face, which is continuously updated by experience, functions as a norm for coding identity. Sex-contingent figural face aftereffects indicate that different norms are maintained for male and female faces but do not directly implicate them in coding identity. Here, we investigated whether sex-specific norms are used to code the identities of mal...

In this paper we highlight and address some of the problems involved in teaching HIV/AIDS education in southern and eastern Africa, and especially in generating open discussion among pupils about sex and sexuality. The paper draws on the findings of a UNICEF-funded study, in which we were involved, as research consultants (2001). The study focused on 'young people, gender, sexuality and HIV/AID...

The purpose of this study was to explore the associations between the qualities of different types of relationships in school, social support and loneliness in adolescence. Using a sample (N=1674) of adolescent students randomly selected from middle schools, we found boys' loneliness was influenced by the qualities of opposite-sex, teacher-student and same-sex relationships, whereas girls' lone...

Sex-discriminating facial features are examples of visual information involved in guiding social behavior. We used functional magnetic resonance imaging (fMRI) to assess brain responses in face-relevant brain areas in men and women during exposure to neutral male and female faces. An increased fMRI signal was found in the left amygdala and adjacent anterior temporal regions in men, but not in w...

Twins compared with singletons and monozygous (MZ) compared with dizygous (DZ) twins are at increased risk of fetal and infant death, cerebral palsy and many congenital anomalies. The aim of this study is to investigate whether zygosity is a risk factor for the sudden infant death syndrome (SIDS). Birth registration data and draft infant death certificates for all multiple births in England and...

Social theorists have suggested relationship practice changes such as rising rates of nonmarital cohabitation imply external anchors are lifting with relations become increasingly individualized and fragile. These suppositions in part based on theories commitment which taken conventional characteristics marriage a blueprint from to compare. Reporting findings an in-depth qualitative study Engla...

The present study examined the effects of social status on adult neurogenesis in an extreme cooperative breeder: the naked mole rat. These animals live in large colonies of up to 300 individuals, with a strict reproductive dominance hierarchy; one female and one to three males breed, and all other members are socially subordinate and reproductively suppressed. We examined the effects of social ...

Reflective opposite sex norms are behavior that an individual believes the opposite sex prefers them to do. The current study extends research on this recently introduced construct by examining estimates and influences of reflective norms on drinking in a large high-risk heterosexual sample of male and female college students from two universities. Both gender and Greek-affiliation served as po...

The modern sciences more often use the gender factor in the interpretative procedure. Demographers also have chance to involve this factor in analysis. There are some indicators of gender gaps or inequalities in distribution of resources located in both microenvironment (households) and macroenvironment. Human capital formation and development also demonstrate gender inequalities in process. Po...