Macrogenetics reveals multifaceted influences of environmental variation on vertebrate population genetic diversity across the Americas.

The broad scale distribution of population-specific genetic diversity (GDP ) across taxa remains understudied relative to species diversity gradients, despite its relevance for systematic conservation planning. We used nuclear DNA data collected from 3678 vertebrate populations across the Americas to assess the role of environmental and spatial variables in structuring the distribution of GDP , a key component of adaptive potential in the face of environmental change. We specifically assessed non-linear trends for a metric of GDP, expected heterozygosity (HE ), and found more evidence for spatial hotspots and cold spots in HE rather than a strict pattern with latitude. We also detected inconsistent relationships between HE and environmental variables, where only 11 of 30 environmental comparisons among taxa groups were statistically significant at the .05 level, and the shape of significant trends differed substantially across vertebrate groups. Only one of six taxonomic groups, freshwater fishes, consistently showed significant relationships between HE and most (four of five) environmental variables. The remaining groups had statistically significant relationships for either two (amphibians, reptiles), one (birds, mammals), or no variables (anadromous fishes). Our study highlights gaps in the theoretical foundation upon which macrogenetic predictions have been made thus far in the literature, as well as the nuances for assessing broad patterns in GDP among vertebrate groups. Overall, our results suggest a disconnect between patterns of species and genetic diversity, and underscores that large-scale factors affecting genetic diversity may not be the same factors as those shaping taxonomic diversity. Thus, careful spatial and taxonomic-specific considerations are needed for applying macrogenetics to conservation planning.

Evaluating Benefits, Costs, and Social Value as Predictors of Gratitude.

Although much is known about cooperation, the internal decision rules that regulate motivations to initiate and maintain cooperative relationships have not been thoroughly explored. Here, we focus on how acts of benefit delivery and perceptions of social value inform gratitude, an emotion that promotes cooperation. We evaluated alternate information-processing models to determine which inputs and internal representations best account for the intensity with which people report experiencing gratitude. Across two experiments (Ns = 257 and 208), we tested 10 models that consider multiple variables: the magnitude of benefits conferred on beneficiaries, the magnitude of costs incurred by benefactors, beneficiaries' perception of how much benefactors value their welfare, and beneficiaries' value for the welfare of their benefactors. Across both studies, only beneficiaries' change in social valuation for their benefactors consistently predicted gratitude. Results point to the need for further research and contribute to the growing literature linking cooperation, social emotions, and social valuation.

Evaluating the efficacy of common humanity-enhanced exposure for socially anxious young adults.

Despite some evidence of the benefits of self-compassion training among socially anxious individuals, little is known about whether enhancing self-compassion prior to exposure therapy increases initial exposure engagement. Additionally, manipulations have relied on broad definitions of self-compassion, rendering it difficult to distinguish the impact of individual components. This study employed three experiential exercises designed to enhance one facet of self-compassion-common humanity. Socially anxious undergraduates (N = 63) were randomized in groups to 1) common humanity-enhanced exposure (n = 32) or 2) exposure alone (n = 31). In the common humanity condition, participants wrote self-compassionately, shared fears, and completed a common humanity-focused lovingkindness meditation. All participants then completed a speech exposure in front of live judges followed by an optional second exposure. Within the common humanity condition, positive self-responding to the speech exposure increased (b = 0.30, p = .026). Common humanity participants also remained in the first exposure longer, relative to exposure alone (b = -30.92, p = .002). Participants rated exercises as at least moderately helpful, with sharing fears rated most helpful. In sum, a brief group-based multi-modal common humanity induction represents a promising approach to improving initial engagement with feared contexts among socially anxious individuals.

Politicians polarize and experts depolarize public support for COVID-19 management policies across countries.

Political polarization impeded public support for policies to reduce the spread of COVID-19, much as polarization hinders responses to other contemporary challenges. Unlike previous theory and research that focused on the United States, the present research examined the effects of political elite cues and affective polarization on support for policies to manage the COVID-19 pandemic in seven countries (n = 12,955): Brazil, Israel, Italy, South Korea, Sweden, the United Kingdom, and the United States. Across countries, cues from political elites polarized public attitudes toward COVID-19 policies. Liberal and conservative respondents supported policies proposed by ingroup politicians and parties more than the same policies from outgroup politicians and parties. Respondents disliked, distrusted, and felt cold toward outgroup political elites, whereas they liked, trusted, and felt warm toward both ingroup political elites and nonpartisan experts. This affective polarization was correlated with policy support. These findings imply that policies from bipartisan coalitions and nonpartisan experts would be less polarizing, enjoying broader public support. Indeed, across countries, policies from bipartisan coalitions and experts were more widely supported. A follow-up experiment replicated these findings among US respondents considering international vaccine distribution policies. The polarizing effects of partisan elites and affective polarization emerged across nations that vary in cultures, ideologies, and political systems. Contrary to some propositions, the United States was not exceptionally polarized. Rather, these results suggest that polarizing processes emerged simply from categorizing people into political ingroups and outgroups. Political elites drive polarization globally, but nonpartisan experts can help resolve the conflicts that arise from it.

Flexible approaches for estimating partial eta squared in mixed-effects models with crossed random factors.

Mixed-effects models are frequently used in a variety of disciplines because they can appropriately specify multiple sources of variation. However, precisely because they distinguish between multiple sources of variation, it is difficult to specify a standardized effect size, such as η2. Several approaches to this problem have been proposed, but most do not address models with crossed random factors, and none allows for the range of data and models that researchers typically test. For example, no existing approach handles random slopes for a continuous predictor. We introduce several new, flexible approaches to estimating η2 in mixed-effect models with crossed random factors. We then conduct a simulation to assess new and old methods. We examine their respective strengths and weaknesses and offer recommendations for a simple approach based on the work of Snijders and Bosker (2011).

Structured reflection increases intentions to reduce other people's health risks during COVID-19.

People believe they should consider how their behavior might negatively impact other people, Yet their behavior often increases others' health risks. This creates challenges for managing public health crises like the COVID-19 pandemic. We examined a procedure wherein people reflect on their personal criteria regarding how their behavior impacts others' health risks. We expected structured reflection to increase people's intentions and decisions to reduce others' health risks. Structured reflection increases attention to others' health risks and the correspondence between people's personal criteria and behavioral intentions. In four experiments during COVID-19, people (N  = 12,995) reported their personal criteria about how much specific attributes, including the impact on others' health risks, should influence their behavior. Compared with control conditions, people who engaged in structured reflection reported greater intentions to reduce business capacity (experiment 1) and avoid large social gatherings (experiments 2 and 3). They also donated more to provide vaccines to refugees (experiment 4). These effects emerged across seven countries that varied in collectivism and COVID-19 case rates (experiments 1 and 2). Structured reflection was distinct from instructions to carefully deliberate (experiment 3). Structured reflection increased the correlation between personal criteria and behavioral intentions (experiments 1 and 3). And structured reflection increased donations more among people who scored lower in cognitive reflection compared with those who scored higher in cognitive reflection (experiment 4). These findings suggest that structured reflection can effectively increase behaviors to reduce public health risks.

When election expectations fail: Polarized perceptions of election legitimacy increase with accumulating evidence of election outcomes and with polarized media.

The present study, conducted immediately after the 2020 presidential election in the United States, examined whether Democrats' and Republicans' polarized assessments of election legitimacy increased over time. In a naturalistic survey experiment, people (N = 1,236) were randomly surveyed either during the week following Election Day, with votes cast but the outcome unknown, or during the following week, after President Joseph Biden was widely declared the winner. The design unconfounded the election outcome announcement from the vote itself, allowing more precise testing of predictions derived from cognitive dissonance theory. As predicted, perceived election legitimacy increased among Democrats, from the first to the second week following Election Day, as their expected Biden win was confirmed, whereas perceived election legitimacy decreased among Republicans as their expected President Trump win was disconfirmed. From the first to the second week following Election Day, Republicans reported stronger negative emotions and weaker positive emotions while Democrats reported stronger positive emotions and weaker negative emotions. The polarized perceptions of election legitimacy were correlated with the tendencies to trust and consume polarized media. Consumption of Fox News was associated with lowered perceptions of election legitimacy over time whereas consumption of other outlets was associated with higher perceptions of election legitimacy over time. Discussion centers on the role of the media in the experience of cognitive dissonance and the implications of polarized perceptions of election legitimacy for psychology, political science, and the future of democratic society.

The sex premium in religiously motivated moral judgment.

Recent theorizing suggests that religious people's moral convictions are quite strategic (albeit unconsciously so), designed to make their worlds more amenable to their favored approaches to solving life's basic challenges. In a meta-analysis of 5 experiments and a preregistered replication, we find that religious identity places a sex premium on moral judgments, causing people to judge violations of conventional sexual morality as particularly objectionable. The sex premium is especially strong among highly religious people, and applies to both legal and illegal acts. Religion's influence on moral reasoning emphasizes conventional sexual norms, and may reflect the strategic projects to which religion has been applied throughout history. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Hierarchical generalized additive models in ecology: an introduction with mgcv.

In this paper, we discuss an extension to two popular approaches to modeling complex structures in ecological data: the generalized additive model (GAM) and the hierarchical model (HGLM). The hierarchical GAM (HGAM), allows modeling of nonlinear functional relationships between covariates and outcomes where the shape of the function itself varies between different grouping levels. We describe the theoretical connection between HGAMs, HGLMs, and GAMs, explain how to model different assumptions about the degree of intergroup variability in functional response, and show how HGAMs can be readily fitted using existing GAM software, the mgcv package in R. We also discuss computational and statistical issues with fitting these models, and demonstrate how to fit HGAMs on example data. All code and data used to generate this paper are available at: github.com/eric-pedersen/mixed-effect-gams.

Scale-dependent interactions between tree canopy cover and impervious surfaces reduce daytime urban heat during summer.

As cities warm and the need for climate adaptation strategies increases, a more detailed understanding of the cooling effects of land cover across a continuum of spatial scales will be necessary to guide management decisions. We asked how tree canopy cover and impervious surface cover interact to influence daytime and nighttime summer air temperature, and how effects vary with the spatial scale at which land-cover data are analyzed (10-, 30-, 60-, and 90-m radii). A bicycle-mounted measurement system was used to sample air temperature every 5 m along 10 transects (∼7 km length, sampled 3-12 times each) spanning a range of impervious and tree canopy cover (0-100%, each) in a midsized city in the Upper Midwest United States. Variability in daytime air temperature within the urban landscape averaged 3.5 °C (range, 1.1-5.7 °C). Temperature decreased nonlinearly with increasing canopy cover, with the greatest cooling when canopy cover exceeded 40%. The magnitude of daytime cooling also increased with spatial scale and was greatest at the size of a typical city block (60-90 m). Daytime air temperature increased linearly with increasing impervious cover, but the magnitude of warming was less than the cooling associated with increased canopy cover. Variation in nighttime air temperature averaged 2.1 °C (range, 1.2-3.0 °C), and temperature increased with impervious surface. Effects of canopy were limited at night; thus, reduction of impervious surfaces remains critical for reducing nighttime urban heat. Results suggest strategies for managing urban land-cover patterns to enhance resilience of cities to climate warming.

Visual preferences for direct-gaze faces in infant macaques (Macaca mulatta) with limited face exposure.

From birth, human and nonhuman primates attend more to faces with direct gaze compared with averted gaze, and previous studies report that attention to the eyes is linked to the emergence of later social skills. Here, we explored whether early experiences influence attraction to eye contact in infant macaques by examining their attention to face pairs varying in their gaze direction across the first 13 weeks of life. Infants raised by human caretakers had limited conspecific interactions (nursery-reared; N = 16) and were compared to infants raised in rich social environments (mother-reared; N = 20). Both groups looked longer to faces and the eyes of direct compared to averted-gaze faces. Looking to all faces and eyes also increased with age. Nursery-reared infants did not display age-associated increases in attention to direct-gaze faces specifically, suggesting that, while there may be an initial preference for direct-gaze faces from birth, social experiences may support its early development.

The unresponsive avenger: More evidence that disinterested third parties do not punish altruistically.

Many social scientists believe humans possess an evolved motivation to punish violations of norms-including norm violations that do not harm them directly. However, most empirical evidence for so-called altruistic punishment comes from experimental economics games that create experimental demand for third-party punishment, raising the possibility that the third-party punishment uncovered in these experiments has been motivated by a desire to appear concerned about social norms rather than by actual concern about upholding them. Here we present the results of five experiments in which we used an aggression paradigm to contrast second-party and third-party punishment with minimal experimental demand. We also summarize the results of these experiments meta-analytically. We found robust evidence that participants who were insulted by a stranger experienced anger and punished the insulter. To a lesser degree, participants who witnessed a friend receive an insult also became angry and punished the insulter. In contrast, we found robust evidence that participants who witnessed a stranger receive an insult did not punish the insulter, although they did experience modest amounts of anger. In only one experiment did we find any punishment on behalf of a stranger, and this result could plausibly be explained by the desire to escape the moral censure of other bystanders. Our results suggest that experimental designs that rely on demand-laden methods to test hypotheses about third-party punishment may have overstated the case for the existence of this trait. (PsycINFO Database Record

Re-examination of Oostenbroek et al. (2016): evidence for neonatal imitation of tongue protrusion.

The meaning, mechanism, and function of imitation in early infancy have been actively discussed since Meltzoff and Moore's (1977) report of facial and manual imitation by human neonates. Oostenbroek et al. (2016) claim to challenge the existence of early imitation and to counter all interpretations so far offered. Such claims, if true, would have implications for theories of social-cognitive development. Here we identify 11 flaws in Oostenbroek et al.'s experimental design that biased the results toward null effects. We requested and obtained the authors' raw data. Contrary to the authors' conclusions, new analyses reveal significant tongue-protrusion imitation at all four ages tested (1, 3, 6, and 9 weeks old). We explain how the authors missed this pattern and offer five recommendations for designing future experiments. Infant imitation raises fundamental issues about action representation, social learning, and brain-behavior relations. The debate about the origins and development of imitation reflects its importance to theories of developmental science.

Experience with anonymous interactions reduces intuitive cooperation.

The Social Heuristics Hypothesis claims that cooperation is intuitive because it is positively reinforced in everyday life, where behaviour typically has reputational consequences1,2. Consequently, participants will cooperate in anonymous laboratory settings unless they either reflect on the one-shot nature of the interaction or learn through experience with such settings that cooperation does not promote self-interest. Experiments reveal that cognitive-processing manipulations (which increase reliance on either intuition or deliberation) indeed affect cooperation3, but may also introduce confounds4,5. Here, we elide the interpretation issues created by between-subjects designs in showing that people are less cooperative over time in laboratory paradigms in which cooperation cannot promote self-interest, but are just as cooperative over time in paradigms that have the potential to promote self-interest. Contrary to previous findings6,7, we find that cooperation is equally intuitive for men and women: unilateral giving did not differ across gender at the first study session, and decreased equally for both genders across sessions.

Signatures of the collapse and incipient recovery of an overexploited marine ecosystem.

The Northwest Atlantic cod stocks collapsed in the early 1990s and have yet to recover, despite the subsequent establishment of a continuing fishing moratorium. Efforts to understand the collapse and lack of recovery have so far focused mainly on the dynamics of commercially harvested species. Here, we use data from a 33-year scientific trawl survey to determine to which degree the signatures of the collapse and recovery of the cod are apparent in the spatial and temporal dynamics of the broader groundfish community. Over this 33-year period, the groundfish community experienced four phases of change: (i) a period of rapid, synchronous biomass collapse in most species, (ii) followed by a regime shift in community composition with a concomitant loss of functional diversity, (iii) followed in turn by periods of slow compositional recovery, and (iv) slow biomass growth. Our results demonstrate how a community-wide perspective can reveal new aspects of the dynamics of collapse and recovery unavailable from the analysis of individual species or a combination of a small number of species. Overall, we found evidence that such community-level signals should be useful for designing more effective management strategies to ensure the persistence of exploited marine ecosystems.

Testing the arousal hypothesis of neonatal imitation in infant rhesus macaques.

Neonatal imitation is the matching of (often facial) gestures by newborn infants. Some studies suggest that performance of facial gestures is due to general arousal, which may produce false positives on neonatal imitation assessments. Here we examine whether arousal is linked to facial gesturing in newborn infant rhesus macaques (Macaca mulatta). We tested 163 infants in a neonatal imitation paradigm in their first postnatal week and analyzed their lipsmacking gestures (a rapid opening and closing of the mouth), tongue protrusion gestures, and yawn responses (a measure of arousal). Arousal increased during dynamic stimulus presentation compared to the static baseline across all conditions, and arousal was higher in the facial gestures conditions than the nonsocial control condition. However, even after controlling for arousal, we found a condition-specific increase in facial gestures in infants who matched lipsmacking and tongue protrusion gestures. Thus, we found no support for the arousal hypothesis. Consistent with reports in human newborns, imitators' propensity to match facial gestures is based on abilities that go beyond mere arousal. We discuss optimal testing conditions to minimize potentially confounding effects of arousal on measurements of neonatal imitation.

Nonhierarchical Dispersal Promotes Stability and Resilience in a Tritrophic Metacommunity.

Community interactions (e.g., predation, competition) can be characterized by two factors: their strengths and how they are structured between and within species. Both factors play a role in determining community dynamics. In addition to trophic interactions, dispersal acts as an interaction between separate populations. As with other interactions, the structure of dispersal can affect the stability of a system. However, the primary structure that has been studied in consumer-resource models has been hierarchical dispersal, where between-patch dispersal rates increase with trophic level. Here we use analytical, numerical, and simulation approaches on a two-patch, three-species metacommunity model to investigate the relationship between structure and community stability and resilience. We show that metacommunity stability is greater in systems with both weak and strong dispersal rates. Our system is stabilized by the formation of patterns when predators disperse frequently and herbivores disperse rarely, and via asynchrony when both predators and herbivores disperse infrequently. Our results show how interaction strengths within both trophic and spatial networks shape metacommunity stability.

Reassessing intertemporal choice: human decision-making is more optimal in a foraging task than in a self-control task.

Many contemporary concerns (e.g., addiction, failure to save) can be viewed as intertemporal choice problems in which the consequences of choices are realized at different times. In some laboratory paradigms used to study intertemporal choice, non-human animals demonstrate a preference for immediacy (impulsive choice) that results in failures to maximize the amount of reward received. There is evidence, however, suggesting that such non-optimal impulsive choice may be due to a mismatch between the standard presentation of options in the laboratory (e.g., a "larger-later" and a "smaller-sooner" option) and the way that options occur in natural settings (e.g., foraging). We present evidence that human impulsive choice is similarly affected: in two experiments, decisions were more optimal when options were presented in a format sharing features with the evolutionarily important problem of foraging compared to when options were presented in the standard format. These findings suggest a more nuanced view of intertemporal choice and support the adoption of ideas from foraging theory into the study of human decision making.