A Test of Haldane's Rule in Neodiprion Sawflies and Implications for the Evolution of Postzygotic Isolation in Haplodiploids.

AbstractHaldane's rule-a pattern in which hybrid sterility or inviability is observed in the heterogametic sex of an interspecific cross-is one of the most widely obeyed rules in nature. Because inheritance patterns are similar for sex chromosomes and haplodiploid genomes, Haldane's rule may apply to haplodiploid taxa, predicting that haploid male hybrids will evolve sterility or inviability before diploid female hybrids. However, there are several genetic and evolutionary mechanisms that may reduce the tendency of haplodiploids to obey Haldane's rule. Currently, there are insufficient data from haplodiploids to determine how frequently they adhere to Haldane's rule. To help fill this gap, we crossed a pair of haplodiploid hymenopteran species (Neodiprion lecontei and Neodiprion pinetum) and evaluated the viability and fertility of female and male hybrids. Despite considerable divergence, we found no evidence of reduced fertility in hybrids of either sex, consistent with the hypothesis that hybrid sterility evolves slowly in haplodiploids. For viability, we found a pattern opposite to that of Haldane's rule: hybrid females, but not males, had reduced viability. This reduction was most pronounced in one direction of the cross, possibly due to a cytoplasmic-nuclear incompatibility. We also found evidence of extrinsic postzygotic isolation in hybrids of both sexes, raising the possibility that this form or reproductive isolation tends to emerge early in speciation in host-specialized insects. Our work emphasizes the need for more studies on reproductive isolation in haplodiploids, which are abundant in nature but underrepresented in the speciation literature.

100 years of Haldane's rule.

Haldane's rule is one of the 'two rules of speciation'. It states that if one sex is 'absent, rare or sterile' in a hybrid population, then that sex will be heterogametic. Since Haldane first made this observation, 100 years have passed and still questions arise over how many independent examples exist and what the underlying causes of Haldane's rule are. This review aims to examine research that has occurred over the last century. It seeks to do so by discussing possible causes of Haldane's rule, as well as gaps in the research of these causes that could be readily addressed today. After 100 years of research, it can be concluded that Haldane's rule is a complicated one, and much current knowledge has been accrued by studying the model organisms of speciation. This has led to the primacy of dominance theory and faster-male theory as explanations for Haldane's rule. However, some of the most interesting findings of the 21st century with regard to Haldane's rule have involved investigating a wider range of taxa emphasizing the need to continue using comparative methods, including ever more taxa as new cases are discovered.

The influence of vestibular system and fetal presentation on handedness, cognitive and motor development: A comparison between cephalic and breech presentation.

Genetics are undoubtedly implicated in the ontogenesis of laterality. Nonetheless, environmental factors, such as the intrauterine environment, may also play a role in the development of functional and behavioral lateralization. The aim of this study was to test the Left-Otolithic Dominance Theory (LODT; Previc, 1991) by investigating a hypothetical developmental pattern where it is assumed that a breech presentation, which is putatively associated with a dysfunctional and weakly lateralized vestibular system, can lead to weak handedness and atypical development associated with language and motor difficulties. We used the ALSPAC cohort of children from 7 to 10 years of age to conduct our investigation. Our results failed to show an association between the vestibular system and fetal presentation, nor any influence of the latter on hand preference, hand performance, or language and motor development. Bayesian statistical analyses supported these findings. Contrary to our LODT-derived hypotheses, this study offers evidence that fetal presentation does not influence the vestibular system's lateralization and seems to be a poor indicator for handedness. Nonetheless, we found that another non-genetic factor, prematurity, could lead to atypical development of handedness.

Disrupting White racial dominance: How White antiracists challenge the racial status quo in interpersonal relationships.

As White activists are growing the racial justice movement, their antiracism frequently disrupts the racial hierarchy, which features whiteness in a dominant role, especially in interpersonal relationships. We investigate how White antiracists disrupt whiteness in interpersonal relationships. We interviewed 16 White antiracists who had experienced significant relationship distance due to their antiracism. We conducted thematic analyses to understand the conflicts that emerged between antiracists and their White counterparts as activists challenged White racial dominance. Antiracists disrupted whiteness by exercising social power to punish racist offenders. In response, their White counterparts resisted these challenges by exerting their instruments of power to sanction antiracists. The conflict with White people led antiracists to build greater personal and social capacity for antiracist activism. This study illustrates how conflicts can emerge during social change efforts even at the microlevel as parties exercise power to contest or support the status quo.

Balanced truncation for model reduction of biological oscillators.

Model reduction is a central problem in mathematical biology. Reduced order models enable modeling of a biological system at different levels of complexity and the quantitative analysis of its properties, like sensitivity to parameter variations and resilience to exogenous perturbations. However, available model reduction methods often fail to capture a diverse range of nonlinear behaviors observed in biology, such as multistability and limit cycle oscillations. The paper addresses this need using differential analysis. This approach leads to a nonlinear enhancement of classical balanced truncation for biological systems whose behavior is not restricted to the stability of a single equilibrium. Numerical results suggest that the proposed framework may be relevant to the approximation of classical models of biological systems.

Partnering With Oppressive Institutions for Social Change: Roles, Ethics, and a Framework for Practicing Accountability.

Community psychology is driven by the values of social justice, action, and accountability to oppressed groups, with a large body of literature devoted to understanding how to work in partnership with communities through participatory methodologies (e.g., community-based participatory research, participatory action research). However, some community psychologists may work in partnership with oppressive institutions (e.g., the criminal justice system) in order to transform these institutions toward greater equity and justice. In this conceptual review, I explore the unique challenges and opportunities of partnering with oppressive institutions for social change. First, I define oppressive institutions as those that are hierarchy-enhancing under social dominance theory and draw on theories of social change to explain when and why we might choose to partner with these institutions in research and action. I then review case studies of the ethical dilemmas community psychologists have faced in such partnerships. Finally, I propose a conceptual framework for practicing accountability when partnering with hierarchy-enhancing institutions. This framework includes specific practices that research/evaluation teams might incorporate into their relationships with institutional partners and communities impacted by the institution.

Haldane's Rule: Genetic Bases and Their Empirical Support.

There are few patterns in evolution that are as rigidly held as Haldane's rule (HR), which states, "When in the first generation between hybrids between 2 species, 1 sex is absent, rare, or sterile, that sex is always the heterogametic sex." Yet despite considerable attention for almost a century, questions persist as to how many independent examples exist and what is (are) the underlying genetic cause(s). Here, we review recent evidence extending HR to plants, where previously it has only been documented in animals. We also discuss recent comparative analyses that show much more variation in sex-chromosome composition than previously recognized, thus increasing the number of potential independent origins of HR dramatically. Finally, we review the standing of genetic theories proposed to explain HR in light of the new examples and new molecular understanding.

The View from Inside the System: How Police Explain Their Response to Sexual Assault.

Prior research has documented the problematic community response to sexual assault: the majority of sexual assaults reported to police are never prosecuted. Social dominance theory suggests that this response is a form of institutional discrimination, intended to maintain existing social structures, and that police personnel likely draw upon shared ideologies to justify their decision-making in sexual assault case investigations. This study drew upon social dominance theory to examine how police justified their investigatory decisions to identify potential leverage points for change. The study revealed that the likelihood of a case referral to the prosecutor increased with each additional investigative step completed; of the different types of justifications provided by police for a less-than-thorough investigative response and stalled case, blaming the victim for the poor police investigation proved to be the most damaging to case progression; and the type of explanation provided by police was impacted by specific case variables. As suggested by social dominance theory, the study demonstrates that police rely on several different mechanisms to justify their response to sexual assault; implementing criminal justice system policies that target and interrupt these mechanisms has the potential to improve this response, regardless of specific case factors.

Asymmetric intergroup bullying: The enactment and maintenance of societal inequality at work.

What does inequality mean for dysfunctional organizational behaviours, such as workplace bullying? This article argues that workplace bullying can be understood as a manifestation of intergroup dynamics originating beyond the organization. We introduce the construct of asymmetric intergroup bullying: the disproportionate mistreatment of members of low status groups, with the intended effect of enhancing the subordination of that group in society at large. Analysis of data from 38 interviews with public and private sector workers in Turkey depicts a pattern of asymmetric intergroup bullying, undertaken to achieve organizational and broader sociopolitical goals. Respondents reported bullying acts used to get rid of unwanted personnel, with the goal of avoiding severance pay, or of removing supporters of the former government from positions of political and economic influence. Bullying was also described as working towards the dominance of the sociocultural worldview of one political group over another. We discuss asymmetric intergroup bullying as one mechanism through which acute intergroup hierarchy in the broader society corrupts management practice and employee interactions, in turn exacerbating economic inequality along group lines.

Power Moderates the Effects of Social Dominance Orientation on Punishment: An Experimental Analysis.

In this study, it was hypothesized that experimentally manipulated levels of power would moderate the association of dispositional social dominance orientation (SDO) with preferences for harsh punishment. In particular, we expected to detect a stronger effect for dispositional SDO in the low-power condition, relying on the notion that low power enhances sensitivity to threats to the status quo, and that high SDO individuals are particularly motivated to enforce hierarchy-enhancing measures as punishment. SDO scores were measured two months prior to the experiment, and then immediately after the experimental session. As expected, preexperimental SDO interacted with the power manipulation. We found stronger preexperimental SDO effects on punishment among low-power participants. We also anticipated and found that individuals high in SDO increased further their postexperimental SDO scores if assigned to a high-power condition. The discussion focuses on the importance of SDO effects among low-status groups and on how situational roles shape dispositional self-descriptions.

Do gender differences matter to workplace bullying?

BACKGROUND: Workplace bullying has become an omnipresent problem in most organizations. Gender differences have recently received increasing attention in the workplace bullying domain. OBJECTIVE: Integrating social dominance theory with gender role theory, this study explores whether male minority and supervisor gender are related to the incidence of workplace bullying. METHODS: Data from 501 public servants employed in the tax administration institute of Taiwan was collected via a questionnaire and analyzed using hierarchical regression. RESULTS: Male minority reported more workplace bullying than did the female majority. Subordinates working with male supervisors had more exposure to bullying than those working with female supervisors. However, male supervisors did not exacerbate the relationship between male minority and workplace bullying, while females exposure to workplace bullying was attenuated when working with male supervisors. CONCLUSIONS: These findings confirm the important role of gender differences when predicting bullying at work and support the view that gender is not merely an individual antecedent of bullying, but rather acts as a social factor to influence the incidence of workplace bullying.

Genetic architecture of isolation between two species of Silene with sex chromosomes and Haldane's rule.

Examination of the genetic architecture of hybrid breakdown can provide insight into the genetic mechanisms of commonly observed isolating phenomena such as Haldane's rule. We used line-cross analysis to dissect the genetic architecture of divergence between two plant species that exhibit Haldane's rule for male sterility and rarity, Silene latifolia and Silene diclinis. We made 15 types of crosses, including reciprocal F1, F2, backcrosses, and later-generation crosses, grew the seeds to flowering, and measured the number of viable ovules, proportion of viable pollen, and sex ratio. Typically, Haldane's rule for male rarity in XY animal hybrids is explained by interactions involving recessive X-linked alleles that are deleterious when hemizygous (dominance theory), whereas sterility is explained by rapid evolution of spermatogenesis genes (faster-male evolution). In contrast, we found that the genetic mechanisms underlying Haldane's rule between the two Silene species did not follow these conventions. Dominance theory was sufficient to explain male sterility, but male rarity likely involved faster-male evolution. We also found an effect of the neo-sex chromosomes of S. diclinis on the extreme rarity of some hybrid males. Our findings suggest that the genetic architecture of Haldane's rule in dioecious plants may differ from those commonly found in animals.

Environmental consequences of the desire to dominate and be superior.

A belief in human dominance over nature lies at the heart of current environmental problems. In this article, we extend the theoretical scope of social dominance theory by arguing that social dominance orientation (SDO) is an important variable in understanding person-environment relations. We argue that individuals high in SDO are more willing to exploit the environment in unsustainable ways because SDO promotes human hierarchical dominance over nature. Four studies provide support for this perspective. High SDO was associated with lower levels of environmental concern in a nationally representative New Zealand sample (Study 1) and in country-level data across 27 nations (Study 2). SDO was also positively related to utilization attitudes toward nature (Study 3) and mediated the gender difference in beliefs about anthropogenic climate change (Study 4), and both occurred independently of right-wing authoritarianism. Implications for the human-dominated view of nature subscribed to by those high in SDO are discussed.