Children's social wariness toward a different-race stranger relates to individual differences in temperament.

When children first meet a stranger, there is great variation in how much they will approach and engage with the stranger. While individual differences in this type of behavior-called social wariness-are well-documented in temperament research, surprisingly little attention has been paid to the social groups (such as race) of the stranger and how these characteristics might influence children's social wariness. In contrast, research on children's social bias and interracial friendships rarely examines individual differences in temperament and how temperament might influence cross-group interactions. The current study bridges the gap across these different fields of research by examining whether the racial group of an unfamiliar peer or adult moderates the association between temperament and the social wariness that children display. Utilizing a longitudinal dataset that collected multiple measurements of children's temperament and behaviors (including parent-reported shyness and social wariness toward unfamiliar adults and peers) across early childhood, we found that 2- to 7-year-old children with high parent-reported shyness showed greater social wariness toward a different-race stranger compared to a same-race stranger, whereas children with low parent-reported shyness did not. These results point to the importance of considering racial group membership in temperament research and the potential role that temperament might play in children's cross-race interactions. RESEARCH HIGHLIGHTS: Previous research on temperament has not considered how the race of strangers could influence children's social wariness. We find evidence that 2- to 7-year-old children with high parent-reported shyness show greater social wariness toward a different-race stranger compared to a same-race stranger. These results point to the importance of considering racial group membership in temperament research. Our findings also suggest temperament may play a role in children's cross-race interactions.

Multiple-Perpetrator and Solo-Offender Sexual Assaults Between Strangers: Differences and Predictive Variables.

Multiple-perpetrator rape is an under-studied topic, but there has been a recent increase in studies on the differences between multiple-perpetrator sexual offenses and the ones perpetrated by solo offenders. This study aims to have a deeper understanding of the differences between multiple-perpetrator and solo-offender sexual assaults committed by strangers, from a sample of 400 sexual aggressions reported to the Spanish police in 2010. Differences were explored on variables related to characteristics of perpetrators, the assault (approach, control, maintenance, termination, and sexual behavior), and the victims. Data were obtained from police files on sexual assaults committed around the country. Significant differences found were similar to other studies conducted in other countries and proved that multiple perpetrator assaults committed by strangers are a different subtype. Additionally, four predictive variables of multiple-perpetrator rape were identified: older age (OR = 0.943, 95% CI = [0.92, 0.97]), alcohol or drug use (OR = 2.499, 95% CI = [1.50, 4.32]), non-Spanish nationals (OR = 1.980, 95% CI = [1.14, 3.45]), and use of violence to control the victim (OR = 2.465, 95% CI = [1.03, 5.90]). The cultural and leisure characteristics of Spanish society provide facilitating opportunities for multiple-perpetrator rapes and prevention strategies should be urgently addressed.

Nonstranger and Stranger Sexual Homicides in Mainland China: Comparing the Modus Operandi of Male Sexual Murderers.

Although studies have been made of different subtypes of individuals who committed sexual homicides, the research into nonstranger and stranger sexual homicides remains limited. This study therefore aimed to examine whether those who sexually murder nonstrangers differ from those who kill strangers. Data derived from police records, court documents, and published case reports spanning a 31 year period (1988-2018) in mainland China were used to examine the modus operandi of 127 males who committed sexual homicides (45 nonstranger and 82 stranger cases). Relative to nonstranger sexual homicides, stranger sexual homicides were more likely to have been committed by individuals with a previous sexual offense conviction and the victims were more likely to have been single and employed at the time of the offense. Furthering the analysis, a logistic regression found that individuals who targeted strangers were significantly more likely to have committed their homicide at an outdoor location, to have been sexually motivated, and to have used murder weapons that required more physical strength than those who killed nonstranger victims. These findings can be informative to law enforcement agents and security professionals in their investigative processes.

Is There an "Expert" Stranger Rapist?

The concept of expertise applied to the criminal context assumes that offenders are driven by the abilities to both maximize the payoffs and minimize the risks associated with the crime-commission. This study tested the articulation between these two types of decisions taken by stranger rapists to successfully commit their crime. Specifically, this study aims to identify whether offenders whose modus operandi is indicative of criminal expertise are more likely to use forensic awareness strategies. Multivariate analyses conducted on 1,551 cases showed that stranger rapists who adopted behaviors indicative of expertise were more likely to use forensic awareness strategies to decrease the risk of police detection. Mixed associations were found between the number of forensic awareness strategies and their nature (i.e., protecting identity vs. destroying evidence) and rapists' expertise, thus leading to a four-type theoretical classification of expertise: novice, bold, opportunistic, and expert stranger rapists. Implications for research and practice are discussed.

Infant's gaze in a teasing task with an experimenter or parent: A naturalistic approach.

We assessed infant's gaze in a teasing task in New York City public spaces. The task was administered to two different groups of 5- to 13-month-old infants. We used a between participants design across two studies. In Study 1 an experimenter administered the task to these infants (n = 79), whereas a parent did so in Study 2 (n = 79). The adult engaged the infant with a toy and then pulled it away to one side by counting to 7. A second trial to the other side was repeated. Infants passed the teasing task if they looked to the adult's face within the first 5 seconds after removing the toy in at least one trial. In Study 1, we found that infants looked to the experimenter's face after teasing by 7 months of age. In Study 2, infants did not show any significant gazes to the parent's face after teasing at any age. Most trained parents successfully administered the teasing task to their infant. A teasing game played by an adult stranger (e.g., experimenter) may be optimal to elicit infant's gaze in a naturalistic setting. Implications for developing cost-effective social-cognitive milestone measures in non-laboratory settings are discussed.

Male song sparrows have elevated testosterone in response to neighbors versus strangers.

Upon hearing a conspecific signal, animals must assess their relationship with the signaller and respond appropriately. Territorial animals usually respond more aggressively to strangers than neighbors in a phenomenon known as the "dear enemy effect". This phenomenon likely evolved because strangers represent a threat to an animal's territory tenure and parentage, whereas neighbors only represent a threat to an animal's parentage because they already possess a territory (providing territory boundaries are established and stable). Although the dear enemy effect has been widely documented using behavioral response variables, little research has been conducted on the physiological responses of animals to neighbors versus strangers. We sought to investigate whether the dear enemy effect is observed physiologically by exposing territorial male song sparrows (Melospiza melodia) to playback simulating a neighbor or a stranger, and then collecting blood samples to measure plasma testosterone levels. We predicted that song sparrows would exhibit increased testosterone levels after exposure to stranger playback compared to neighbor playback, due to the role testosterone plays in regulating aggression. Contrary to our prediction, we found that song sparrows had higher testosterone levels after exposure to neighbor playback compared to stranger playback. We discuss several explanations for our result, notably that corticosterone may regulate the dear enemy effect in male song sparrows and this may inhibit plasma testosterone. Future studies will benefit from examining corticosterone in addition to testosterone, to better understand the hormonal underpinnings of the dear enemy effect.

A comparison of intimate partner and other sexual assault survivors' use of different types of specialized hospital-based violence services.

BACKGROUND: Little is known about the health service utilization of women sexually assaulted by their intimate partners, as compared with those sexually assaulted by other perpetrators. To address this gap, we describe the use of acute care services post-victimization, as well as a broad range of survivor and assault characteristics, across women assaulted by current or former intimate partners, other known assailants, and strangers. METHODS: Information was gathered from individuals presenting to 30 hospital-based sexual assault and domestic violence treatment centres using a standardized data collection form. We examined the data from 619 women 16 years of age or older who were sexually assaulted by one assailant. RESULTS: Women sexually assaulted by a current or former intimate partner were less likely than those assaulted by another known assailant or a stranger to have been administered emergency contraception (p < 0.001) or prophylaxis for sexually transmitted infections (p < 0.001), and counselled for potential use of HIV post-exposure prophylaxis (p < 0.001). However, these women were more likely than those in the other two groups to have had their injuries documented with photographs (p < 0.001), have undergone a risk assessment (p = 0.008), and/or have engaged in safety planning (p < 0.001). CONCLUSIONS: Women sexually assaulted by current or former intimate partners utilized services offered by sexual assault and domestic violence treatment centres differently than those assaulted by other known assailants and strangers. This may reflect their different health, forensic, and social needs, as well as the importance of offering care tailored to their particular circumstances.

Stranger danger awareness in Williams syndrome.

BACKGROUND: The developmental disorder Williams syndrome (WS) is characterised by a distinctive cognitive profile and an intriguing social phenotype. Individuals with the disorder are often highly social engaging with familiar and unfamiliar people and once in an interaction they often show subtle abnormalities of social behaviour. Atypically increased approach to unfamiliar people is widely reported in the existing literature for both children and adults. Parents frequently report interactions with unfamiliar people as a major concern. METHODS: In this study we aimed to evaluate 'stranger danger' awareness using a video vignette task with individuals who had WS. When linked to other components of the WS phenotype (e.g. reduced intellectual ability, increased social approach) an awareness of stranger danger is particularly important. RESULTS: Qualitative and quantitative data showed that young people with WS have difficulties making judgements about whether or not to trust and engage in conversation with unfamiliar people. Qualitative data showed that individuals with WS often suggested that they would engage in an interaction with an unfamiliar person. CONCLUSIONS: The findings have substantial implications for the safety of young people with the disorder and emphasise the need for intervention regarding this behaviour.

Evaluation of a stranger safety training programme for adults with Williams syndrome.

BACKGROUND: Individuals with Williams syndrome (WS) are reported to display increased sociability towards strangers, leading to increased social vulnerability. No research has examined real life interactions of adults with WS towards strangers and no interventions have been implemented to teach stranger safety skills to this population. METHOD: Twenty-one adults with WS participated in 3 days of behaviour skills training to learn how to respond to a stranger lure. Skill acquisition was assessed in situ; confederate strangers approached participants, presented a lure and recorded the participants' response. RESULTS: Prior to intervention, 14% of participants walked away from a stranger. Participants were able to accurately use the skills in role play. After training, 62% of participants said 'no' and walked away and only 14% agreed to leave with the stranger during in situ assessments. CONCLUSIONS: Individuals with WS are at-risk but can learn how to appropriately respond to lures from strangers. Further research is needed to increase use of safety skills in various conditions.

Familiarity Determines Whether Accent Affects Attitudes and Behaviors of the Listener.

Previous research found that accents cause the listener to exhibit prejudice toward the speaker. The present study tested whether the familiarity of the listener and speaker moderated this effect. Study 1 tested this question in a simulated recruit scenario and found that participants were less likely to recruit candidates with an accent, but this effect existed only when the candidate was a stranger to the interviewer, not when the candidate was an acquaintance. Study 2 retested this question in a scenario of talking one-on-one and also found that the effect of accent existed only when they were strangers, not when they were acquaintances. Both studies suggested that the effect of accent on the attitude and behavior of the listener vanished when the speaker and listener were familiar with each other. This work offers insights for understanding the effect of accent on social interaction from the perspective of the familiarity of the speaker and listener and reveals the moderated role of familiarity in the dynamic of the effect of accent.

Neighbour-stranger discrimination in an African wood dove inhabiting equatorial rainforest.

We investigated within- and between-individual song variation and song-based neighbour-stranger discrimination in a non-learning bird species, the blue-headed wood-dove (Turtur brehmeri), which inhabits lowland rainforests of West and Central Africa. We found that songs of this species are individually specific and have a high potential for use in individual recognition based on the time-frequency pattern of note distribution within song phrases. To test whether these differences affect behaviour, we conducted playback experiments with 19 territorial males. Each male was tested twice, once with the songs of a familiar neighbour and once with the songs of an unfamiliar stranger. We observed that males responded more aggressively to playback of a stranger's songs: they quickly approached close to the speaker and spent more time near it. However, no significant differences between treatments were observed in the vocal responses. In addition, we explored whether responses differed based on the song frequency of the focal male and/or that of the simulated intruder (i.e., playback), as this song parameter is inversely related to body size and could potentially affect males' decisions to respond to other birds. Song frequency parameters (of either the focal male or the simulated intruder) had no effect on the approaching response during playback. However, we found that the pattern of response after playback was significantly affected by the song frequency of the focal male: males with lower-frequency songs stayed closer to the simulated intruder for a longer period of time without singing, while males with higher-frequency songs returned more quickly to their initial song posts and resumed singing. Together, these results depict a consistently strong response to strangers during and after playback that is dependent on a male's self-assessment rather than assessment of a rival's strength based on his song frequency. This work provides the first experimental evidence that doves (Columbidae) can use songs for neighbour-stranger discrimination and respond according to a "dear enemy" scheme that keeps the cost of territory defence at a reasonable level.

Crime-scene and offender characteristics in conventional and nonconventional stranger homicides committed by male offenders in Sweden.

In Sweden, from 1990 to 2013, most homicides occurred between family members, friends or acquaintances: the annual rate of incidents between unacquainted offenders and victims ranged between 8% and 13%. In the majority of these "stranger homicides," three common motives, as defined by the precipitating event, could be identified: homicides resulting from a spontaneous altercation; homicides committed in the context of a robbery or burglary; and homicides committed in the context of a gangland conflict. The remaining minority-with uncommon or indiscernible motives-could, nonetheless, be categorized according to their nonconventional distinguishing feature: homicides characterized by the offender's ostensibly mentally aberrant behavior; homicides committed in the context of a hate offense or politically motivated offense; homicides committed in the context of a sexual offense; and homicides committed in the context of a mass killing or series of homicides. In this registry-based study of 224 incidents, "conventional" stranger homicides, defined by their commonplace motive, were compared with "nonconventional" stranger homicides, defined by their lack of such motive. The former were more often committed with an accomplice, against a male victim, whereas the latter were more often committed in a public place, after contact initiated by the offender. In the latter, offenders were less often intoxicated at the time of the offense and more often adjudged to suffer from a severe mental disorder. The subcategory of nonconventional stranger homicides characterized by the offender's ostensibly mentally aberrant behavior corresponded largely to both the archetypal stranger-homicide construct and the popular notion "act of madness."

Trust in Acquaintances, Strangers and Institutions among Individuals of Different Socioeconomic Statuses during Public Health Emergencies: The Moderation of Family Structure and Policy Perception.

Trust plays a crucial role in effectively responding to public health emergencies. Drawing on COVID-19 survey data conducted in Hubei, China, during August 2020 with a sample size of 5494, this study investigated the influence of individuals' socioeconomic status on trust in acquaintances, strangers and institutions, and how this relationship is moderated by epidemic prevention, policy perception and family structure. The findings showed that individuals with higher socioeconomic status tend to have higher levels of trust. Those with higher income but being married demonstrate higher trust. When perceiving epidemic prevention policies as stringent, those with higher income display increased trust in acquaintances and institutions; similarly, those with lower education levels exhibit heightened trust in acquaintances and strangers. Individuals working in social organizations express higher trust in strangers; however, their trust is compromised under stringent epidemic prevention policies due to potentially heavier work burdens.

Police Decisions in a Rape Scenario: The Effect of Trauma Response, Forensic Evidence, Stranger-Perpetrators, and Rape Mythology.

This study examined the direct effect of "classic rape" characteristics, and how they were moderated by rape myth endorsement, on the likelihood of arrest, perceived district attorney charge acceptance, and perceived suspect conviction using a formal rape disclosure among a sample of 468 police participants from a sizeable municipal law enforcement agency in one of the fifth largest and most diverse U.S. cities. A randomly assigned, between-subjects factorial vignette design was employed. Manipulations included stereotypical trauma response, forensic medical exam, and perpetrator type. Path modeling revealed statistically significant relations between stereotypical trauma response, forensic medical exam, perpetrator type, and the three outcome variables. Rape myth endorsement moderated the effect of manipulations on the dependent variables. Implications for research and policy are discussed.

Evidence for acoustic discrimination in lemurs: A playback study on wild indris Indri indri.

Indris Indri indri are group-living lemurs that occupy stable territories over several years and perform remarkable long-distance vocal displays. Vocal exchanges between long-term territory neighbors may contribute to assessing reciprocal resource-holding potentials, thus adaptively reducing the costs of territorial defense by limiting aggressive escalation. Previous work showed that indris' songs show distinctive acoustic features at individual and group level. However, the possibility that indris use such cues for individual or group-level recognition has never been investigated experimentally. We conducted a playback experiment to test whether indris discriminate between familiar and nonfamiliar songs. Our rationale lies in the hypothesis of the dear enemy phenomenon, which predicts that territorial animals will show reduced aggression levels toward familiar neighbors compared with novel rivals. We played back stimulus recordings to wild indris from their territory boundaries and examined their responses in terms of vocal and behavioral indicators of willingness to engage in a fight. In line with our predictions, focal animals responded more rapidly and approached more often the speaker in response to playback stimuli of nonfamiliar individuals than to stimuli of neighboring groups. These results indicate that indris can discriminate between different classes of intruders based on distinctive acoustic features of their song choruses. We suggest that increased aggression directed toward unfamiliar intruders may be explained by higher threat levels associated with dispersal and group formation dynamics. We further discuss the relevance of these findings in a strepsirrhine primate model for comparative studies of vocal communication and sociality.

Face-to-face live eye-tracking in toddlers with autism: Feasibility and impact of familiarity and face covering.

Studies utilizing eye-tracking methods have potential to promptly capture real-world dynamics of one of the core areas of vulnerability in autism spectrum disorders (ASD), selective social attention. So far, no studies have successfully reported utilizing the method to examine social attention in toddlers with neurodevelopmental vulnerabilities in real world and challenging settings such as an interactive face-to-face. This study examined the feasibility and validity of live eye-tracking method in response to live interaction occurring in several contexts in toddlers with and without ASD. Forty-seven toddlers with ASD, with atypical development (ATYP), or typically developing (TD), underwent a 30-s live eye-tracking procedure during a face-to-face interaction with a masked stranger using child-directed-speech (16 ASD, 14 ATYP, 17 TD; Mage = 23.44 months, SD = 6.02). Out of this group of toddlers, 29 (10 ASD, 8 ATYP, 11 TD, Mage = 21.97 months, SD = 5.76) underwent the same procedure with one of their maskless parent. Task completion rate, calibration accuracy, and affective response (feasibility measures) as well as attention to the task and the social partner (validity measures) were examined. Task completion rate and calibration accuracy were excellent. Despite the challenging context of face-to-face interaction, the toddlers exhibited a neutral affect, and high attention to the task and the speaker. As anticipated, toddlers with ASD looked less at the social partner compared with control groups. However, attention was comparable between the Stranger and Parent conditions, indicating that the effect was consistent regardless of presence of face covering or the familiarity of the interactive partner. The study demonstrates the high feasibility and validity of a live eye-tracking task involving face-to-face interaction in neurodiverse toddlers with social vulnerabilities. The effect of diminished attention to social partners in toddlers with autism is robust and present when interacting with an unfamiliar person and parent. The results suggest that a brief live eye-tracking method constitutes a promising ecologically valid candidate biomarker and potential intervention outcome in autism.

Psychosis and the Risk of Stranger Homicides.

Introduction: Psychosis increases the risk of committing homicide, but it remains unclear whether it also affects victim selection. Individual cases of stranger homicide elicit a lot of public attention and outrage, even though evidence of their incidence is scarce. Methods: Forensic psychiatric reports of 389 patients who had committed homicide in Finland during 1980-2014 were examined to determine the relationship between the offender and the victim. The stranger homicide incidence derived from perpetrators with psychosis was compared to a comparative incidence derived from a group of perpetrators without psychosis (other mental disorders were not excluded) over the time frame 2003-2014. Stranger homicide incidence rates were calculated using Finnish population averages of the study years, assuming a Poisson distribution and reported as per 100 000 person-years among potential victims in the Finnish general population. Results: Three hundred and eighty nine patients with psychosis had committed 414 homicides, with 40 complete stranger victims and 15 victims known for less than 24 h. Complete stranger homicide incidence committed by individuals with psychosis was 0.022 per 100 000 person-years and 0.13 for individuals without psychosis. When also including victims known for < 24 h, the incidence was 0.031 for individuals with psychosis and 0.28 for individuals without psychosis per 100 000 person-years. Discussion: Nine out of ten stranger homicides are committed by individuals without psychosis. However, on the basis of a 3.1% prevalence of psychotic disorders in Finland, individuals with psychosis have about a 3- to 5-fold risk of committing stranger homicides as compared to individuals without psychosis.

Using Video Modeling to Teach Abduction-Prevention Skills to Children with Autism Spectrum Disorder.

Video modeling was used to teach children with autism spectrum disorder how to respond to taped stranger lure scenarios and in-situ stranger lures. A multiple baseline design across participants was used to assess treatment effects. Measures consisted of reported verbal and motor responses to three abduction scenarios and actual responses to stranger lures planted near the children's therapy program and within the children's communities. Each child displayed increases in appropriate responses to taped abduction scenarios and in-situ stranger lures post-treatment. One year following the intervention 90% of the participants maintained and generalized the skills. This study indicated that children with ASD could learn to respond to taped stranger lure scenarios and correspondingly demonstrate these skills in situ and maintain these skills for at least one year following treatment.

The Latin stranger-science, or l'anthropologie among the Lusitanians.

This essay traces the connected histories of Portuguese and French anthropology in the late nineteenth century. By looking at a Portuguese scientific institution, the Carlos Ribeiro Society, it considers how French race science, known as anthropologie, was adopted and adapted across the European Latin world as a type of "stranger-science." That is: as an authoritative outsider scientific formation, installed into national terrain in accordance with insider strategies for turning foreign elements into native forms of scientific sovereignty and modernity. French anthropology's international diffusion becomes meaningful in the light of the Portuguese incorporating what was foreign and modern as a means to generate vitality, and authority endogenously in their own national context. Hence, addressing the circulation of stranger-sciences can pave the way for an original conceptualizing of the transnational life of race science across and even beyond the Latin world.

Stranger danger: A meta-analysis of the dear enemy hypothesis.

The dear enemy hypothesis predicts that territorial individuals will be less aggressive toward known neighbors than to strangers. This hypothesis has been well studied and there is a wealth of data demonstrating its prevalence in some taxa. However, a quantitative synthesis is needed to test the generality of the phenomenon, identify key mechanisms driving the behavior, and guide future research. In this study, we conduct a meta-analysis and, we test the importance of the location of intrusion, the type of experiment conducted (field, laboratory, or neutral arenas), and the sex and breeding status of territory holders, on the occurrence of dear enemy behavior. We also test how various ecological and life history traits, such as territory type, stimulus of intrusion, and taxonomic group, affect the magnitude of dear enemy behavior. We find that this phenomenon is common and that taxonomic class and breeding status are correlated with the expression of dear enemy behaviors. Further, we found that the way authors measure aggression influences the likelihood of identifying dear enemy responses, and thus we discuss potential pitfalls of dear enemy studies. Considering this conclusion, we discuss future lines of inquiry that could more directly examine the mechanisms of the dear enemy phenomenon.