Table 1.
Social composition of the study population from Chimfunshi Wildlife Orphanage as of the start of our observations (29/05/2021).
Fig 1.
Proportions of attracted, neutral, and dispersed grooming PO-MC pairs, for each individual.
Attracted pairs correspond to grooming happening only in the PO, dispersed pairs correspond to grooming happening only in the MC, and neutral pairs correspond to grooming happening in neither or both. Data comprised of N = 120 matched focals of N = 32 individuals.
Fig 2.
Proportions of attracted, neutral and dispersed play PO-MC pairs, for each individual.
Attracted pairs correspond to play happening only in the PO, dispersed pairs correspond to play happening only in the MC, and neutral pairs correspond to play happening in neither or both. Data comprised of N = 96 matched focals of N = 25 individuals.
Fig 3.
Social closeness scores in focal follows where contagion did and did not take place.
The social closeness measure is the z-transformed dyadic sociality index between observer and stimulus individuals. The mean social closeness value for instances of no contagion vs contagion is shown with a black bar. Data comprised of N = 159 observations of N = 40 chimpanzees.
Fig 4.
Histogram of latencies from observing grooming to first initiating grooming.
Data comprised of N = 54 observations across N = 21 individuals.
Fig 5.
Mean rate of post-observation play across age categories.
Data is grouped into juveniles (3–7 years; N = 34 observations of N = 10 chimpanzees), subadults (8–11 years; N = 20 observations of N = 4 chimpanzees) and adults (12+ years; N = 82 observations of N = 27 chimpanzees). This categorisation is for visualisation purposes, but data were analysed with age as a continuous variable. Upper and lower quartiles are indicated by the box boundaries, and dots indicate outliers.
Fig 6.
Histogram of latencies from observing play to first initiating play.
Data comprised of N = 48 observations across N = 28 individuals.