We investigated the relationships between age, social behavior, and fitness at three levels of organization: the individual, the local social environment, and the population. Replicate groups of forked fungus beetles (Bolitotherus cornutus) were engineered to have either young- or old- biased age structures, and both social and reproductive behaviors were recorded.

These data describe patterns of interaction among 10 mesocosm populations of Bolitotherus cornutus in 2018 and 12 in 2020. In 2020, the 6 "young populations" composed of first-year and two-year-old beetles, and 6 "old populations" composed of two-year-olds and individuals at least three years of age. Social interactions were defined as individuals being in close proximity (within 5cm) of one another and were collected through scan sampling 3x a day for 8 days in each session. Behavioral datasets were error-checked to remove all unidentifiable or dead beetles and all impossible or partially recorded interactions. Weighted social networks were created using the simple ratio index. Weighted clustering and shortest path lengths were calculated in the R package tnet.

In addition to the data and scripts used for the analysis, we provide the raw data and the scripts used for finding and correcting errors.