Growth and pruning of mushroom body Kenyon cell dendrites during worker behavioral development in the paper wasp, Polybia aequatorialis (Hymenoptera: Vespidae)

Adult workers of some social insect species show dramatic behavioral changes as they pass through a sequence of task specializations. In the paper wasp, Polybia aequatorialis, female workers begin adult life within the nest tending brood, progress to maintaining and defending the nest exterior, and ultimately leave the nest to forage. The mushroom body (MB) calyx neuropil increases in volume as workers progress from in-nest to foraging tasks. In other social Hymenoptera (bees and ants), MB Kenyon cell dendrites, axons and synapses change with the transition to foraging, but these neuronal effects had not been studied in wasps. Furthermore, the on-nest worker of Polybia wasps, an intermediate task specialization not identified in bees or ants, provides the opportunity to study pre-foraging worker class transitions. We asked whether Kenyon cell dendritic arborization varies with the task specialization of Polybia workers observed in the field near Monteverde, Costa Rica. Golgi-impregnated arbors in the lip and collar calyces, which receive a predominance of olfactory and visual input, respectively, were quantified using Sholl’s concentric circles and a novel application of virtual spherical probes. Arbors of the lip varied in a manner reminiscent of honeybees, with foragers having the largest and in-nest workers having the smallest arbors. In contrast, arbors of the collar were largest in foragers but smallest in on-nest workers. Thus, progression through task specializations in P. aequatorialis involves subregion specific dendritic growth and regression in the MB neuropil. These results may reflect the sensitivity of Kenyon cell dendritic structure to specialization dependent social and sensory experience.     

Race-based perceptual asymmetries underlying face processing in infancy

Adults process other-race faces differently than own-race faces. For instance, a single other-race face in an array of own-race faces attracts Caucasians’ attention, but a single own-race face among other-race faces does not. This perceptual asymmetry has been explained by the presence of an other-race feature in other-race faces and its absence in own-race faces; this difference is thought to underlie race-based differences in face processing. We examined the developmental origins of this mechanism in two groups of Caucasian 9-month-olds. Infants in the experimental group exhibited a preference for a pattern containing a single Asian face among seven Caucasian faces over a pattern containing a single Caucasian face among seven Asian faces. This preference was not driven by the majority of elements in the images, because a control group of infants failed to exhibit a preference between homogeneous patterns containing eight Caucasian versus eight Asian faces. The results demonstrate that an other-race face among own-race faces attracts infants’ attention but not vice versa. This perceptual asymmetry suggests that the other-race feature is available to Caucasians by 9 months of age, thereby indicating that mechanisms of specialization in face processing originate early in life.     

More Than Just IQ: School Achievement Is Predicted by Self-Perceived Abilities—But for Genetic Rather Than Environmental Reasons

ABSTRACT— Evidence suggests that children's self-perceptions of their abilities predict their school achievement even after one accounts for their tested cognitive ability (IQ). However, the roles of nature and nurture in the association between school achievement and self-perceived abilities (SPAs), independent of IQ, is unknown. Here we reveal that there are substantial genetic influences on SPAs and that there is genetic covariance between SPAs and achievement independent of IQ. Although it has been assumed that the origins of SPAs are environmental, this first genetic analysis of SPAs yielded a heritability of 51% in a sample of 3,785 pairs of twins, whereas shared environment accounted for only 2% of the variance in SPAs. Moreover, multivariate genetic analyses indicated that SPAs predict school achievement independently of IQ for genetic rather than environmental reasons. It should therefore be possible to identify "SPA genes" that predict school achievement independently of "IQ genes."     

The Irony of Harmony: Intergroup Contact Can Produce False Expectations for Equality

ABSTRACT— Positive intergroup contact has been a guiding framework for research on reducing intergroup tension and for interventions aimed at that goal. We propose that beyond improving attitudes toward the out-group, positive contact affects disadvantaged-group members' perceptions of intergroup inequality in ways that can undermine their support for social change toward equality. In Study 1, participants were assigned to either high- or low-power experimental groups and then brought together to discuss either commonalities between the groups or intergroup differences. Commonality-focused contact, relative to difference-focused contact, produced heightened expectations for fair (i.e.,  egalitarian) out-group behavior among members of disadvantaged groups. These expectations, however, proved unrealistic when compared against the actions of members of the advantaged groups. Participants in Study 2 were Israeli Arabs (a disadvantaged minority) who reported the amount of positive contact they experienced with Jews. More positive intergroup contact was associated with increased perceptions of Jews as fair, which in turn predicted decreased support for social change. Implications for social change are considered.     

Alienable Speech: Ideological Variations in the Application of Free-Speech Principles

Although freedom of speech is a Constitutionally protected and widely endorsed value, political tolerance research finds that people are less willing to protect speech they dislike than speech they like ( Gibson, 2006 ). Research also suggests liberal-conservative differences in political tolerance ( Davis & Silver, 2004 ). We measured U.S. citizens' political tolerance for speech acts, while manipulating the speaker's ethnicity and the speech's ideological content. Speech criticizing Americans was protected more strongly than was speech criticizing Arabs, especially among more politically liberal respondents. Liberals also reported greater free-speech support. Respondents expressed greater political tolerance for a speaker when he was an exemplar of the criticized group, but showed equal political tolerance for speakers whose group membership (as a White or Black American) was irrelevant to the speech. Finally, implicit political identity showed convergent validity with explicit political identity in predicting speech tolerance, and implicit racial and ethnic preferences showed variable prediction of speech tolerance across the two studies.     

Perceptions of the Woman Who Breastfeeds: The Role of Erotophobia,Sexism, and Attitudinal Variables

Perceptions of breastfeeding women were studied in a sample of 201 predominately European American college students. Both men and women had very positive perceptions of breastfeeding women as compared to bottlefeeding women. As predicted, erotophobic women and men had less favorable impressions of the breastfeeding woman than did erotophilic individuals. Men, but not women, who scored high on Glick and Fiske's Benevolent Sexism or Hostile Sexism scales (Glick & Fiske, 1996) had more favorable impressions of the breastfeeding woman than did those with low scores. As predicted, this effect was larger for Benevolent Sexism than for Hostile Sexism. No relationships were found between impressions of breastfeeding women and the Hostility Toward Women Scale (Lonsway & Fitzgerald, 1995) or the Trait Guilt and Moral Standards scales (Jones, Schratter, & Kugler, 2000). The results supported hypotheses that sexualization of the breast, discomfort with sexual stimuli, and sexist attitudes are related to perceptions of the breastfeeding woman.     

Evolution as Revelation of a Triune God

In 1917 Pierre Teilhard de Chardin wrote an essay that proposes union as a way to observe how the process of evolution takes place. He spent the remainder of his life broadening and sharpening the vision, which was based on union in nature. We propose that this vision and the historical development of thermodynamics and classical statistical mechanics offer insight into union and even into the divine life that many Christians believe to be triadic. We briefly situate union in the triune divine life in early Christian tradition as it was believed and practiced. We then interpret three stages of development in the sciences of thermodynamics and statistical mechanics that support the theme of union in nature. Next we describe the development of Teilhard's thought during his scientific career and his tests of the theme of union, principally in his private journals, now being edited. We offer examples of Teilhard's application of union to his own spiritual life and compare his understanding of union with those of Paul the Apostle and John of the Cross. Finally, although the Christian God's triadic life was not a particular concern of Teilhard, we propose union in nature as a vestige of the divine life.     

The Relationship of Pregnancy Status to Job Satisfaction: An Exploratory Analysis

Forty-three women who had worked outside of the home prior to becoming pregnant and had returned to the same place of employment after the birth of their children participated in the study. To do so, they responded to a two-part questionnaire asking about their work lives (e.g., level of job satisfaction before, during, and after their pregnancies) and demographic characteristics (e.g., occupation). The results indicated that their job satisfaction was significantly greater before their pregnancies than either during or after their pregnancies. Job satisfaction during pregnancy had a significant, positive correlation with satisfaction with organizational maternity leave policies. Perceived reactions from women's coworkers and supervisors were also examined. Implications for these findings for organizations are discussed. Limitations of the study, and how they might be rectified in future research, are also addressed.     

The developmental approach to young children's strategic social cognition and behaviour

This study explores the development of strategic behaviour related to kindness and intelligence dimensions in 3‐ to 8‐year‐old children. Previous research systematically highlighted the affective bias that limited young children's thinking and behaving in strategic terms. We argue that young children are able to grasp specific dimensions of social affordances from personality traits and behaviour exemplifying these traits. The results obtained in the partner choice paradigm revealed a developmental increase in social utility understanding. This supports our hypothesis of early social affordances understanding and provides empirical evidence that affective bias did not drastically influence strategic partner choice in 4‐ to 8‐year‐old children. Copyright © 2002 John Wiley & Sons, Ltd.     

Aggressive Behavior of Passengers, Conflict Management Behavior, and Burnout Among Trolley Car Drivers

A sample of 96 trolley car drivers was used to investigate the relationship between aggressive behavior of passengers and burnout, the moderating effect of conflict management behavior of the drivers on this relationship; and the influence of burnout on customer-friendliness, passenger complaints, and absenteeism. The results show that aggressive behavior of passengers was related to all 3 burnout dimensions. The relationship of aggressive behavior of customers and professional efficacy was qualified by 2 significant interactions with 2 conflict management behavior styles: forcing and avoiding. The interactions showed that too much forcing as well as too much avoiding are related to less professional efficacy for drivers confronted with aggressive behavior. Passenger complaints were only related to less professional efficacy. The customer-friendliness of the drivers was related to less cynicism and more professional efficacy. Absenteeism was only related to exhaustion.