Children's expectations of nationality-based behaviors differ for immigrants and nonimmigrants.

Children in the United States (N = 488, 4-11 years, 239 females, 248 males, one other, 53% White; data collected 2021-2022) participated in three studies investigating their expectations about immigrants. Participants recognized that immigration impacts characters' national identity and behaviors. Although previous research reported that children may essentialize nationality, participants instead reasoned flexibly about immigrant characters.

Infants' Social Evaluation of Helpers and Hinderers: A Large-Scale, Multi-Lab, Coordinated Replication Study.

Evaluating whether someone's behavior is praiseworthy or blameworthy is a fundamental human trait. A seminal study by Hamlin and colleagues in 2007 suggested that the ability to form social evaluations based on third-party interactions emerges within the first year of life: infants preferred a character who helped, over hindered, another who tried but failed to climb a hill. This sparked a new line of inquiry into the origins of social evaluations; however, replication attempts have yielded mixed results.

Probing the impact of exposure to diversity on infants' social categorization.

Humans learn about the world through inductive reasoning, generalizing information about an individual to others in the category. Indeed, by infancy, monolingual children expect people who speak the same language (but not people who speak different languages) to be similar in their food preferences (Liberman et al., 2016).

Expectations of intergroup empathy bias emerge by early childhood.

Across two preregistered studies with children (3-12-year-olds; = 356) and adults ( = 262) from the United States, we find robust expectations for intergroup empathic biases. Participants predicted that people would feel better about ingroup fortunes than outgroup fortunes and worse about ingroup misfortunes than outgroup misfortunes. Expectations of empathic bias were stronger when there was animosity and weaker when there was fondness between groups.

Shared social groups or shared experiences? The effect of shared knowledge on children's perspective-taking.

Although the ability to consider others' visual perspectives to interpret ambiguous communication emerges during childhood, people sometimes fail to attend to their partner's perspective. Two studies investigated whether 4- to 6-year-olds show a "closeness-communication bias" in their consideration of a partner's perspective in a communication task. Participants played a game that required them to take their partner's visual perspective in order to interpret an ambiguous instruction.

Young children apply the homophily principle to their reasoning about social relationships.

People who are in close relationships tend to do and like the same things, a phenomenon termed the "homophily principle." The present research probed for evidence of the homophily principle in 4- to 6-year-old children. Across two experiments, participants ( = 327; 166 girls, 161 boys; located in the Midwestern United States) were asked to predict the closeness of two people based on their preferences.

Infants' learning from distinct negative emotions.

Here we investigated infants' developing ability to use emotional expressions as signals that guide their learning about objects. To do so, we presented 16- to 21-month-old infants ( = 99) with actors who conveyed anger, fear, or pain, and tested infants' generalization of others' emotional expressions (Study 1) and infants' exploration of objects (Study 2). Our findings suggest that infants attend to the information conveyed by emotional expressions: When two expressions provide different information (e.

Children use race to infer who is "in charge".

Children must navigate multifaceted social hierarchies to make sense of the social world. Whereas race and social status covary in many societies, minimal research has examined whether children use race as a status marker. Across three studies, we asked 3- to 11-year-old American children (N = 646) to determine which of two models was "in charge" while varying the models' race and posture cues.

It takes two (or more): The social nature of secrets.

The lion's share of research on secrecy focuses on how deciding to keep or share a secret impacts a secret-keeper's well-being. However, secrets always involve more than one person: the secret-keeper and those from whom the secret is kept or shared with. Although secrets are inherently social, their consequences for people's reputations and social relationships have been relatively ignored.

Origins of homophily: Infants expect people with shared preferences to affiliate.

Homophily structures human social networks: people tend to seek out or be attracted to those who share their preferences or values, and to generally expect social connections between similar people. Here, we probe the nature and extent of infants' homophilic thinking by asking whether infants can use information about other people's shared preferences in the absence of other socially relevant behaviors (e.g.

Social identity and contamination: Young children are more willing to eat native contaminated foods.

Ingesting dangerous substances can lead to illness, or even death, meaning that it is critical for humans to learn how to avoid potentially dangerous foods. However, young children are notoriously bad at choosing foods; they are willing to put nonfoods and disgust elicitors into their mouths. Because food choice is inherently social, we hypothesized that social learning and contamination might separately influence children's decisions about whether to eat or avoid a food.

Keep the cat in the bag: Children understand that telling a friend's secret can harm the friendship.

Secrets play a powerful role in human social relationships. Here, we examine the developmental trajectory of 3- to 10-year-old children's (N = 630) expectations about (a) how relationships impact whether people will keep secrets, and (b) how relationships are impacted when a confidee keeps versus tells a confider's secret. Sophisticated expectations about the role of secrets in relationship maintenance develop across childhood.

Even his friend said he's bad: Children think personal alliances bias gossip.

Children learn about other people through gossip. Although gossip can be a valuable and efficient way to learn about others, evaluating gossip's credibility requires understanding when people may be biased, and using this information to update the truth-value placed on the gossip. For instance, people may be motivated to improve their and their friends' reputations (or to worsen their enemies' reputations).

A lifelong preoccupation with the sociality of moral obligation.

Tomasello provides compelling evidence that children understand that people are morally obligated toward members of their social group. We call for expanding the scope of inquiry to encompass the full developmental trajectory of humans' understanding of the relation between moral obligation, sociality, and stancetaking in interaction. We suggest that humans display a lifelong preoccupation with the sociality of moral obligation.

(Un)common knowledge: Children use social relationships to determine who knows what.

Socially savvy individuals track what they know and what other people likely know, and they use this information to navigate the social world. We examine whether children expect people to have shared knowledge based on their social relationships (e.g.

Children use similarity, propinquity, and loyalty to predict which people are friends.

Friendship fundamentally shapes interactions, and predicting other people's affiliations is crucial for effectively navigating the social world. We investigated how 3- to 11-year-old children use three cues to reason about friendship: propinquity, similarity, and loyalty. In past work, researchers asked children to report on their own friendships and found a shift from an early focus on propinquity to a much later understanding of the importance of loyalty.

Secret to friendship: Children make inferences about friendship based on secret sharing.

Secrets carry valuable social information. Because the content of secrets can be damaging to the secret-keeper's reputation, people should only disclose their secrets to people whom they trust. Therefore, tracking which people know each other's secrets can be used as cue of social relationships: If one person tells another person a secret, those people are likely friends.

Understanding the development of folk-economic beliefs.

Developmental psychology can shed light on (1) the intuitive systems that underlie folk-economic beliefs (FEBs), and (2) how FEBs are created and revised. Boyer & Petersen (B&P) acknowledge the first, but we argue that they do not seriously consider the second. FEBs vary across people (and within a person), and much of this variation may be explained by socialization, social context, and social learning.

Feeling out a link between feeling and infant sociomoral evaluation.

Recent research has shown that infants selectively approach prosocial versus antisocial characters, suggesting that foundations of sociomoral development may be present early in life. Despite this, to date, the mental processes involved in infants' prosocial preferences are poorly understood. To explore a possible role of emotions in early social evaluations, the current studies examined whether four samples of infants and toddlers express different emotional reactions after observing prosocial (giving) versus antisocial (taking) events.

The early social significance of shared ritual actions.

Many rituals are socially stipulated such that engaging in a group's rituals can fundamentally signal membership in that group. Here, we asked whether infants infer information about people's social affiliation based on whether those people perform the same ritualistic action versus different actions. We presented 16-month-old infants with two people who used the same object to achieve the same goal: turning on a light.

The Origins of Social Categorization.

Forming conceptually-rich social categories helps people to navigate the complex social world by allowing them to reason about the likely thoughts, beliefs, actions, and interactions of others, as guided by group membership. Nevertheless, social categorization often has nefarious consequences. We suggest that the foundation of the human ability to form useful social categories is in place in infancy: social categories guide the inferences infants make about the shared characteristics and social relationships of other people.

Children's expectations about conventional and moral behaviors of ingroup and outgroup members.

Although children demonstrate robust social preferences for ingroup members early in ontogeny, it is not yet clear whether these preferences are based on children generally liking people who are more familiar or on children holding specific biased beliefs about people in their ingroup as compared with people in their outgroup. Here, we investigated the origins of humans' propensity to link ingroup members with positive behaviors and outgroup members with negative behaviors by asking whether linguistic group membership influences children's expectations of how people will act. Our findings indicate that the effect of group membership on children's expectations about other people's actions varies across both domain (moral and conventional) and age.

Children use partial resource sharing as a cue to friendship.

Resource sharing is an important aspect of human society, and how resources are distributed can provide people with crucial information about social structure. Indeed, a recent partiality account of resource distribution suggested that people may use unequal partial resource distributions to make inferences about a distributor's social affiliations. To empirically test this suggestion derived from the theoretical argument of the partiality account, we presented 4- to 9-year-old children with distributors who gave out resources unequally using either a partial procedure (intentionally choosing which recipient would get more) or an impartial procedure (rolling a die to determine which recipient would get more) and asked children to make judgments about whom the distributor was better friends with.

Early emerging system for reasoning about the social nature of food.

Selecting appropriate foods is a complex and evolutionarily ancient problem, yet past studies have revealed little evidence of adaptations present in infancy that support sophisticated reasoning about perceptual properties of food. We propose that humans have an early-emerging system for reasoning about the social nature of food selection. Specifically, infants' reasoning about food choice is tied to their thinking about agents' intentions and social relationships.