Dynamics of social contact

Most people may not suspect how much can be predicted about whom in their social network they are likely to contact, who is likely to contact them, and when. My colleagues and I have characterized distributional and temporal patterns underlying contact probability in both humans and chimpanzees. The distribution of contact probability across the members of a person's social network is highly skewed, following an exponential function. In addition, the frequency of past contact, the recency of the last contact, and the spacing of past contacts over time systematically predict the probability of future contact (Pachur et al., 2013; Pachur et al., 2014). Chimpanzees show similar patterns (Stevens et al., 2016). Because social contact is key to social transmission and cooperation, a better characterization of the dynamics of social contact promises a more precise understanding and prediction of social systems. Further, the patterns of contact interact with memory to influence the evolution of cooperation (Stevens et al., 2018).