Young children's adaptive partner choice in cooperation and competition contexts.

Choosing adequate partners is essential for cooperation, but how children calibrate their partner choice to specific social challenges is unknown. In two experiments, 4- to 7-year-olds (N = 189, 49% girls, mostly White, data collection: 03.2021-09.2022) were presented with partners in possession of different positive qualities. Children then recruited partners for hypothetical tasks that differed with respect to the quality necessary for success. Children and the selected partner either worked together toward a common goal or competed against each other. From age 5, children selectively chose individuals in possession of task-relevant qualities as cooperative partners while avoiding them as competitors. Younger children chose partners indiscriminately. Children thus learn to strategically adjust their partner choice depending on context-specific task demands and different social goals.

Prospection and delay of gratification support the development of calculated reciprocity.

Humans frequently benefit others strategically to elicit future cooperation. While such forms of calculated reciprocity are powerful in eliciting cooperative behaviors even among self-interested agents, they depend on advanced cognitive and behavioral capacities such as prospection (representing and planning for future events) and extended delay of gratification. In fact, it has been proposed that these constraints help explain why calculated reciprocity exists in humans and is rare or even absent in other animals. The current study investigated the cognitive foundation of calculated reciprocity by examining its ontogenetic emergence in relation to key aspects of children's cognitive development. Three-to-five-year-old children from the US (N = 72, mostly White, from mixed socioeconomic backgrounds) first completed a cognitive test battery assessing the cognitive capacities hypothesized to be foundational for calculated reciprocity. In a second session, children participated in a calculated reciprocity task in which they could decide how many resources to share with a partner who later had the opportunity to reciprocate (reciprocity condition) and with a partner who could not reciprocate (control condition). Results indicated a steep developmental emergence of calculated reciprocity between 3 and 5 years of age. Further analyses showed that measures of delay of gratification and prospection were important predictors of children's rate of calculated reciprocity, even when controlling for age and after including a measure of verbal ability. By contrast, theory of mind abilities were unrelated to children's reciprocal behavior. This is the first systematic investigation of essential cognitive capacities for calculated reciprocity. We discuss prospection and delay of gratification as two domain-general capacities that are utilized for calculated reciprocity and which could explain developmental as well as species-differences in cooperation.

How fairness and dominance guide young children's bargaining decisions.

Reaching agreements in conflicts is an important developmental challenge. Here, German 5-year-olds (N = 284, 49% female, mostly White, mixed socioeconomic backgrounds; data collection: June 2016-November 2017) faced repeated face-to-face bargaining problems in which they chose between fair and unfair reward divisions. Across three studies, children mostly settled on fair divisions. However, dominant children tended to benefit more from bargaining outcomes (in Study 1 and 2 but not Study 3) and children mostly failed to use leverage to enforce fairness. Communication analyses revealed that children giving orders to their partner had a bargaining advantage and that children provided and responded to fairness reasons. These findings indicate that fairness concerns and dominance are both key factors that shape young children's bargaining decisions.

The development of prosocial behavior-from sympathy to strategy.

Children act prosocially already in their first years of life. Research has shown that this early prosociality is mostly motivated by sympathy for others, but that, over the course of development, children's prosocial behaviors become more varied, more selective, and more motivationally and cognitively complex. Here, we review recent evidence showing that starting at around age 5, children become gradually capable of strategically using prosocial acts as instrumental means to achieve ulterior goals such as to improve their reputation, to be chosen as social partners, to elicit reciprocity, and to navigate interpersonal obligations. Children's sympathy-based prosociality is thus being extended and reshaped into a behavioral repertoire that enables individuals to pursue and balance altruistic, mutualistic, and selfish motives.

Reduced risk-seeking in chimpanzees in a zero-outcome game.

A key component of economic decisions is the integration of information about reward outcomes and probabilities in selecting between competing options. In many species, risky choice is influenced by the magnitude of available outcomes, probability of success and the possibility of extreme outcomes. Chimpanzees are generally regarded to be risk-seeking. In this study, we examined two aspects of chimpanzees' risk preferences: first, whether setting the value of the non-preferred outcome of a risky option to zero changes chimpanzees' risk preferences, and second, whether individual risk preferences are stable across two different measures. Across two experiments, we found chimpanzees (Pan troglodytes, n = 23) as a group to be risk-neutral to risk-avoidant with highly stable individual risk preferences. We discuss how the possibility of going empty-handed might reduce chimpanzees' risk-seeking relative to previous studies. This malleability in risk preferences as a function of experimental parameters and individual differences raises interesting questions about whether it is appropriate or helpful to categorize a species as a whole as risk-seeking or risk-avoidant. This article is part of the theme issue 'Existence and prevalence of economic behaviours among non-human primates'.

Common knowledge that help is needed increases helping behavior in children.

Although there is considerable evidence that at least some helping behavior is motivated by genuine concern for others' well-being, sometimes we also help solely out of a sense of obligation to the persons in need. Our sense of obligation to help may be particularly strong when there is common knowledge between the helper and the helpee that the helpee needs help. To test whether children's helping behavior is affected by having common knowledge with the recipient about the recipient's need, 6-year-olds faced a dilemma: They could either collect stickers or help an experimenter. Children were more likely to help when they and the experimenter had common knowledge about the experimenter's plight (because they heard it together) than when they each had private knowledge about it (because they heard it individually). These results suggest that already in young children common knowledge can heighten the sense of obligation to help others in need.

The strategies used by chimpanzees (Pan troglodytes) and children (Homo sapiens) to solve a simple coordination problem.

One of the challenges of collaboration is to coordinate decisions with others, and recent theories have proposed that humans, in particular, evolved skills to address this challenge. To test this hypothesis, we compared the coordination abilities of 4-year-old children and chimpanzees with a simple coordination problem. To retrieve a reward from a "puzzle box," pairs of individuals were simply required to choose the same 1 of 4 options. If successful, they each received the same reward, so there were no conflicts of interest. Individuals were paired with multiple partners over time. Both species were able to coordinate, but there were marked differences in the way they did so. Children were able to coordinate quickly and flexibly, adjusting easily to new partners, suggesting an understanding of the coordination process. In contrast, chimpanzees took time to converge on a single solution with each new partner, with no gains across partners, suggesting that their coordination was based only on repeating successful past choices. Together, these results support the hypothesis that humans have evolved unique skills for coordinating decisions and actions with others in the pursuit of common interests. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

The development of coordination via joint expectations for shared benefits.

People frequently need to cooperate despite having strong self-serving motives. In the current study, pairs of 5- and 7-year-olds (N = 160) faced a one-shot coordination problem: To benefit, children had to choose the same of 3 reward divisions. They could not communicate or see each other and thus had to accurately predict each other's choices to succeed. One division split the rewards evenly, while the others each favored one child. Five-year-olds mostly chose the division favorable to themselves, resulting in coordination failure. By contrast, 7-year-olds mostly coordinated successfully by choosing the division that split the rewards equally (even though they behaved selfishly in a control condition in which they could choose independently). This suggests that by age 7, children jointly expect benefits to be shared among interdependent social partners "fairly" and that fair compromises can emanate from a cooperative rationality adapted for social coordination. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Children Delay Gratification for Cooperative Ends.

To cooperate effectively, both in small-scale interactions and large-scale collective-action problems, people frequently have to delay gratification (i.e., resist short-term temptations in favor of joint long-term goals). Although delay-of-gratification skills are commonly considered critical in children's social-cognitive development, they have rarely been studied in the context of cooperative decision-making. In the current study, we therefore presented pairs of children (N = 207 individuals) with a modified version of the famous marshmallow test, in which children's outcomes were interdependently linked such that the children were rewarded only if both members of the pair delayed gratification. Children from two highly diverse cultures (Germany and Kenya) performed substantially better than they did on a standard version of the test, suggesting that children are more willing to delay gratification for cooperative than for individual goals. The results indicate that from early in life, human children are psychologically equipped to respond to social interdependencies in ways that facilitate cooperative success.

The psychological mechanisms underlying reciprocal prosociality in chimpanzees (Pan troglodytes).

In both the wild and captivity, chimpanzees engage in reciprocal patterns of prosocial behavior. However, the proximate mechanisms underlying these patterns are unclear. In the current study, we investigated whether chimpanzees prefer to act prosocially toward conspecifics who have directly benefited them (perhaps based on an affective bond) or whether they simply observe the prosocial behavior of others in general (including indirectly to third parties) and preferentially interact with and behave prosocially toward the most prosocial individuals. We found good evidence for direct reciprocity but little evidence for a general (indirect) preference for prosocial individuals. These results suggest that cooperative reciprocity in chimpanzees may be based mostly on social-affective processes and direct interactions. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Children use rules to coordinate in a social dilemma.

Humans are frequently required to coordinate their actions in social dilemmas (e.g. when one of two drivers has to yield for the other at an intersection). This is commonly achieved by individuals following communally known rules that prescribe how people should behave. From relatively early in development, children swiftly pick up the rules of their culture and even start creating game rules among peers. Thus far, however, little is known about children's abilities create rules to regulate their own interactions in social dilemma situations in which individuals' interests are partially in conflict. Here, we repeatedly selected dyads of children (5- and 8-year-olds, N = 144) at random from a group and presented them with a chicken game - a social dilemma in which individuals have conflicting motives but coordination is required to avoid mutual failure. In game breaks, groups reconvened and had the opportunity to think of additional game rules. Eight- but not five-year-olds readily came up with and agreed upon impartial rules to guide their subsequent game behavior (but only after adult prompting). Moreover, when playing by the self-made rules, children achieved higher payoffs, had fewer conflicts, and coordinated with greater efficiency than when playing without a rule - which mimics the functional consequences of rules on a societal level. These findings suggest that by at least age 8, children are capable of using rules to independently self-regulate potential conflicts of interest with peers.

Children, chimpanzees, and bonobos adjust the visibility of their actions for cooperators and competitors.

Chimpanzees and bonobos are highly capable of tracking other's mental states. It has been proposed, however, that in contrast to humans, chimpanzees are only able to do this in competitive interactions but this has rarely been directly tested. Here, pairs of chimpanzees or bonobos (Study 1) and 4-year-old children (Study 2) were presented with two almost identical tasks differing only regarding the social context. In the cooperation condition, players' interests were matched: they had to make corresponding choices to be mutually rewarded. To facilitate coordination, subjects should thus make their actions visible to their partner whose view was partially occluded. In the competition condition, players' interests were directly opposed: the partner tried to match the subject's choice but subjects were only rewarded if they chose differently, so that they benefited from hiding their actions. The apes successfully adapted their decisions to the social context and their performance was markedly better in the cooperation condition. Children also distinguished between the two contexts, but somewhat surprisingly, performed better in the competitive condition. These findings demonstrate experimentally that chimpanzees and bonobos can take into account what others can see in cooperative interactions. Their social-cognitive skills are thus more flexible than previously assumed.

Chimpanzees return favors at a personal cost.

Humans regularly provide others with resources at a personal cost to themselves. Chimpanzees engage in some cooperative behaviors in the wild as well, but their motivational underpinnings are unclear. In three experiments, chimpanzees (Pan troglodytes) always chose between an option delivering food both to themselves and a partner and one delivering food only to themselves. In one condition, a conspecific partner had just previously taken a personal risk to make this choice available. In another condition, no assistance from the partner preceded the subject's decision. Chimpanzees made significantly more prosocial choices after receiving their partner's assistance than when no assistance was given (experiment 1) and, crucially, this was the case even when choosing the prosocial option was materially costly for the subject (experiment 2). Moreover, subjects appeared sensitive to the risk of their partner's assistance and chose prosocially more often when their partner risked losing food by helping (experiment 3). These findings demonstrate experimentally that chimpanzees are willing to incur a material cost to deliver rewards to a conspecific, but only if that conspecific previously assisted them, and particularly when this assistance was risky. Some key motivations involved in human cooperation thus may have deeper phylogenetic roots than previously suspected.

Children coordinate in a recurrent social dilemma by taking turns and along dominance asymmetries.

Humans constantly have to coordinate their decisions with others even when their interests are conflicting (e.g., when 2 drivers have to decide who yields at an intersection). So far, however, little is known about the development of these abilities. Here, we present dyads of 5-year-olds (N = 40) with a repeated chicken game using a novel methodology: Two children each steered an automated toy train carrying a reward. The trains simultaneously moved toward each other so that in order to avoid a crash-which left both children empty-handed-1 train had to swerve. By swerving, however, the trains lost a portion of the rewards so that it was in each child's interest to go straight. Children coordinated their decisions successfully over multiple rounds, and they mostly did so by taking turns at swerving. In dyads in which turn-taking was rare, dominant children obtained significantly higher payoffs than their partners. Moreover, the coordination process was more efficient in turn-taking dyads as indicated by a significant reduction in conflicts and verbal protest. These findings indicate that already by the late preschool years children can independently coordinate decisions with peers in recurrent conflicts of interest. (PsycINFO Database Record

Children use salience to solve coordination problems.

Humans are routinely required to coordinate with others. When communication is not possible, adults often achieve this by using salient cues in the environment (e.g. going to the Eiffel Tower, as an obvious meeting point). To explore the development of this capacity, we presented dyads of 3-, 5-, and 8-year-olds (N = 144) with a coordination problem: Two balls had to be inserted into the same of four boxes to obtain a reward. Identical pictures were attached to three boxes whereas a unique--and thus salient--picture was attached to the fourth. Children either received one ball each, and so had to choose the same box (experimental condition), or they received both balls and could get the reward independently (control condition). In all cases, children could neither communicate nor see each other's choices. Children were significantly more likely to choose the salient option in the experimental condition than in the control condition. However, only the two older age groups chose the salient box above chance levels. This study is the first to show that children from at least age 5 can solve coordination problems by converging on a salient solution.

Conforming to coordinate: children use majority information for peer coordination.

Humans are constantly required to coordinate their behaviour with others. As this often relies on everyone's convergence on the same strategy (e.g., driving on the left side of the road), a common solution is to conform to majority behaviour. In this study, we presented 5-year-old children with a coordination problem: To retrieve some rewards, they had to choose the same of four options as a peer partner--in reality a stooge--whose decision they were unable to see. Before making a choice, they watched a video showing how other children from their partner's peer group had behaved; a majority chose the same option and a minority chose a different one. In a control condition, children watched the same video but could then retrieve the reward irrespective of their partner's choice (i.e., no coordination was necessary). Children followed the majority more often when coordination was required. Moreover, conformers mostly justified their choices by referring to the majority from the video demonstration. This study is the first to show that young children are able to strategically coordinate decisions with peers by conforming to the majority.

"I know you don't know I know " children use second-order false-belief reasoning for peer coordination.

Numerous studies have investigated children's abilities to attribute mental states, but few have examined their ability to recruit these abilities in social interactions. Here, 6-year-olds (N = 104) were tested on whether they can use first- and second-order false-belief understanding to coordinate with peers. Children adjusted their decisions in a coordination game in response to either their partner's erroneous belief or their partner's erroneous belief about their own belief-a result that contrasts with previous findings on the use of higher order "theory of mind" (TOM) reasoning at this age. Six-year-olds are thus able to use their higher order TOM capacities for peer coordination, which marks an important achievement in becoming competent social collaborators.