Investigating the Development of Kinship Detection in Early Childhood

• In Event: Investigating the Development of Social Affiliation Across Infancy and Early Childhood

Abstract

Understanding how we are associated with, and genetically related to, other individuals is fundamental to our survival as a species given the strong influence of kinship detection on our reproductive success (Charlesworth & Willis, 2009; Hamilton, 1964; Lieberman et al., 2007). Although kinship detection has been studied in adults, the origin of this ability, thought to emerge in childhood, has received little attention (Lieberman et al., 2007). A number of social cues, such as facial resemblance (Kaminski et al., 2012) and the observation of maternal investment (Lieberman et al., 2007), can be used to aid in kinship detection, however, it is unknown whether more subtle social cues affect children’s perception of kinship.

In the present study, we investigated whether young children can use partiality of resource sharing (advantageous vs. equal; Liberman & Shaw, 2017) to identify parent-child relationships. Children (n = 68) between the ages of 4- to 7-years-old were read stories about an adult who distributed resources (e.g., cookies) to two children, either in a partial (in favour of the target child) or impartial manner (equally to both children). The participants were then asked to determine if the adult was or was not the mother of the protagonist. Four- to 5-year-olds identified the adult as the protagonist’s mother significantly above chance after viewing partial (p < 0.01), but not impartial (p = 0.25), resource distributions (see Figure 1). Six- to 7-year-olds showed a similar pattern, with their performance significantly above chance in the partial (p = 0.02), but not impartial (p = 0.76), conditions. These findings indicate that resource sharing partiality is a cue that children use to identify parent-child relationships.

The second task consisted of reading participants (n = 67) storybooks in which an adult, identified as either the protagonist’s mother or neighbour, distributed resources (e.g., candy) to two children. Participants were asked to determine how the resources would be divided; specifically, whether the adult would give more, the same, or less to the target child compared to the other child. A multinomial logistic regression showed that adult identity significantly influenced participants’ expectations (p = 0.02); participants were more likely to expect favouritism towards the protagonist when the adult was the child’s mother rather than their neighbour (see Figure 2). Participants were then presented with a hypothetical scenario in which the adult, either the neighbour or mother, allocated the resources equally between the two children. Participants were asked to determine how the protagonist would feel on a modified 4-point Likert scale of emotion (Andrews & Withey, 1976). Across both age groups, participants anticipated that the equal distribution of resources would be more upsetting if the adult was identified as the protagonist’s mother as opposed to their neighbour (p = 0.04). These findings suggest that participants expect partiality in resource sharing for kin rather than non-kin, and that they extend these expectations to anticipate others’ emotional responses when partiality is absent in parent-child interactions.

These findings shed light on how children begin to understand specific types of third-party relationships.

Authors

• Anna Michelle McPhee, University of Toronto
  Presenting Author

• Sinamys Bagh, University of Toronto
  Non-Presenting Author

• Mark A Schmuckler, University of Toronto
  Non-Presenting Author

• Jessica A Sommerville, University of Toronto
  Non-Presenting Author