The development of scope insensitivity in sharing behavior

The singularity effect of identifiable victims is described as the greater willingness to help a single, identified victim than to help a group of victims with the same need (whether victims are identified or not), which occurs even when the single victim is 1 of the group's members. The current research examines the development of this phenomenon in early childhood examining children's actual sharing behavior from the ages of 3.8 to 8.2. Our results show that although younger children are overall less willing to share with others, they give more of their endowment to a group of recipients than to a single recipient. However, this tendency reverses for older children and children with higher level of Theory of Mind, who exhibit the singularity effect by giving more of their endowment to a single, identified target. We discuss possible mechanisms behind this developmental pattern.