低收入女性的生活史特质与繁衍策略的关系

本研究探讨了单一性伙伴（n = 222）、两个以上性伙伴（n = 145）与无性伙伴（n = 106）三组低收入女性的长期配偶偏好、人生阅历、生活史特质与个人特征的关系。研究结果显示三组女性的配偶偏好趋于一致,繁衍策略的组别差异与人生阅历和所处环境具有较高相关,三组女性并不偏好特定类型的配偶。路径分析显示首次生育年龄直接预测配偶数量,受教育水平和初次性交时间对配偶数量与首次生育年龄之间的关系具有显著调节作用;女儿与父亲相处的时间可以预测初次性交年龄。研究结果显示父亲投资影响青少年性行为发展的时间表,人类繁衍的长期进化是性行为变化的根源     

Factors Influencing Perceptions of Breast Cancer Genetic Counseling among Women in an Urban Health Care System

The study assessed perceptions of breast cancer genetic counseling. Focus groups were conducted with twenty women (ages < = 50 years) in a Midwestern, urban health system identified as at above average risk of developing hereditary breast cancer and referred for breast cancer genetic counseling following mammography. All participants associated the words “breast cancer” with fear. African American women who received breast cancer genetic counseling may have channeled their fear into increased vigilance related to breast health. African American women who did not receive breast cancer genetic counseling were most knowledgeable about it. In contrast, Caucasian women who did not receive it reported uncertainty about the role of genetic counseling and testing in assessing breast cancer risk, mistrust in medical professionals, and lack of trust in the accuracy of genetic tests. The results could be used to help develop interventions to improve informed decision-making regarding breast cancer genetic counseling.     

Experimental evidence for spatial learning in cuttlefish (Sepia officinalis)

Laboratory mazes were used to study spatial-learning capabilities in cuttlefish (Sepia offcinalis), using escape for reinforcement. In preliminary observations, cuttlefish in an artificial pond moved actively around the environment and appeared to learn about features of their environment. In laboratory experiments, cuttlefish exited a simple alley maze more quickly with experience and retained the learned information. Similar improvement was not found in open-field mazes or T mazes, perhaps because of motor problems. Cuttlefish learned to exit a maze that required them to find openings in a vertical wall. The wall maze was modified to an arena, and simultaneous discrimination learning and reversal learning were demonstrated. These experiments indicate that cuttlefish improve performance over serial reversals of a simultaneous, visual-spatial discrimination problem.     

Evolution of life-history trade-offs in mate attractiveness and health: comment on Weeden and Sabini (2005)

J. Weeden and J. Sabini's finding of small to no relation between traits rated as attractive in a mate and health of that mate might be interpreted as consistent with C. Darwin's (1859) proposal that these traits are arbitrary signs of beauty. However, such a conclusion would be premature. A combination of consistent empirical findings with nonhuman species and theoretical reasons argues for a continued search for honest signals of genetic fitness and reproductive health in human mate choices. Moreover, (a) even quite small relationships can be important when viewed across generations, and (b) traits that make a potential mate attractive at one age can result in poor health or early death at a later age. These life-history trade-offs greatly complicate the empirical study of attractiveness-health relations, and their potential importance has been underestimated by J. Weeden and J. Sabini.     

Early predictors of middle school fraction knowledge

Recent findings that earlier fraction knowledge predicts later mathematics achievement raise the question of what predicts later fraction knowledge. Analyses of longitudinal data indicated that whole number magnitude knowledge in first grade predicted knowledge of fraction magnitudes in middle school, controlling for whole number arithmetic proficiency, domain general cognitive abilities, parental income and education, race, and gender. Similarly, knowledge of whole number arithmetic in first grade predicted knowledge of fraction arithmetic in middle school, controlling for whole number magnitude knowledge in first grade and the other control variables. In contrast, neither type of early whole number knowledge uniquely predicted middle school reading achievement. We discuss the implications of these findings for theories of numerical development and for improving mathematics learning.     

Evolution and development of boys’ social behavior

An evolutionary analysis of the dynamics of one-on-one and coalitional male–male competition provides a theoretical frame for conceptualizing the evolved functions and proximate developmental forms of the social behavior of boys, and for appreciating why the behavior of boys differs from that of girls. We propose the accompanying selection pressures favored the evolution of motivational and behavioral dispositions in boys and men that facilitate the development and maintenance of large, competitive coalitions and result in the formation of within-coalition dominance hierarchies. Empirical research on boys’ social development is reviewed using this frame and implications for interpreting boys’ social behavior are explored.