The researchers equipped 53 adult Agta living in woodland in seven interconnected residential camps with tracking devices and recorded every social interaction between members of the different camps over a period of one month. The researchers also did the same for a different group, who lived on the coast.

During this time, the tracking devices documented thousands of interactions and provided a comprehensive picture of the Agta's social structure. As expected, people most frequently interacted with members of their own camp, but the study also revealed inter-camp visits almost on a daily basis. "It is fair to say that 'visits between camps' is the social media of current hunter-gatherers," says first author Andrea Migliano, professor of anthropology at UZH. When we need a new solution for a problem, we go online and use multiple sources to obtain information from a variety of people. Hunter-gatherers use their social network in exactly the same way."

A.B. Migliano el al., "Hunter-gatherer multilevel sociality accelerates cumulative cultural evolution," Science Advances (2020). 

DOI: 10.1126/sciadv.aax5913
https://advances.sciencemag.org/content/6/9/eaax5913

Although multilevel sociality is a universal feature of human social organization, its functional relevance remains unclear. Here, we investigated the effect of multilevel sociality on cumulative cultural evolution by using wireless sensing technology to map inter- and intraband social networks among Agta hunter-gatherers. By simulating the accumulation of cultural innovations over the real Agta multicamp networks, we demonstrate that multilevel sociality accelerates cultural differentiation and cumulative cultural evolution. Our results suggest that hunter-gatherer social structures [based on (i) clustering of families within camps and camps within regions, (ii) cultural transmission within kinship networks, and (iii) high intercamp mobility] may have allowed past and present hunter-gatherers to maintain cumulative cultural adaptation despite low population density, a feature that may have been critical in facilitating the global expansion of Homo sapiens.

Fig. 4 Timing and diversity of innovations across real multicamp social networks.
Fig. 4 Timing and diversity of innovations across real multicamp social networks. - (A) Average innovation level (incremental steps A1, A2, A3, B1, B2, B3, and crossover event) by number of rounds, in fully connected (black) and real multicamp networks (forest group) with transmission only to close kin (red). Averages were drawn from 1000 simulations for each transmission scenario. Shaded areas around the curves are SEs estimated for each round and multiplied by 5 for better visualization. (B) Real multicamp network (forest group) showing innovation level achieved by each individual at the end of one typical simulation with transmission only to close kin (light green, A1; green, A2; dark green, A3; light red, B1; red, B2; dark red, B3; the two blue circled individuals are the ones finding the crossover). Innovations are clustered in different parts of the real network. (C and D) Same as above, but for the real multicamp coastal network.