Characterization of hunter-gatherer networks and implications for cumulative culture

Abstract

Social networks in modern societies are highly structured, usually involving frequent contact with a small number of unrelated ‘friends’1. However, contact network structures in traditional small-scale societies, especially hunter-gatherers, are poorly characterized. We developed a portable wireless sensing technology (motes) to study within-camp proximity networks among Agta and BaYaka hunter-gatherers in fine detail. We show that hunter-gatherer social networks exhibit signs of increased efficiency2 for potential information exchange. Increased network efficiency is achieved through investment in a few strong links among non-kin ‘friends’ connecting unrelated families. We show that interactions with non-kin appear in childhood, creating opportunities for collaboration and cultural exchange beyond family at early ages. We also show that strong friendships are more important than family ties in predicting levels of shared knowledge among individuals. We hypothesize that efficient transmission of cumulative culture36 may have shaped human social networks and contributed to our tendency to extend networks beyond kin and form strong non-kin ties.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: Pictures of motes, and of Agta hunter-gatherers (Philippines) wearing motes in armbands.
Figure 2: Global network efficiency and clustering depend on non-kin ties.
Figure 3: Frequency of close-range interactions with close kin and unrelated individuals.
Figure 4: Proportion of interactions by age group and relatedness category.

References

  1. 1

    Saramäki, J. et al. Persistence of social signatures in human communication. Proc. Natl Acad. Sci. USA 111, 942–947 (2014).

    Article  Google Scholar 

  2. 2

    Latora, V. & Marchiori, M. Efficient behavior of small-world networks. Phys. Rev. Lett. 87, 198701 (2001).

    CAS  Article  Google Scholar 

  3. 3

    Rendell, L. et al. Why copy others? Insights from the social learning strategies tournament. Science 328, 208–213 (2010).

    CAS  Article  Google Scholar 

  4. 4

    Powell, A., Shennan, S. & Thomas, M. G. Late Pleistocene demography and the appearance of modern human behavior. Science 324, 1298–1301 (2009).

    CAS  Article  Google Scholar 

  5. 5

    Feldman, M. W. & Laland, K. N. Gene–culture coevolutionary theory. Trends Ecol. Evol. 11, 453–457 (1996).

    CAS  Article  Google Scholar 

  6. 6

    Henrich, J. The Secret of our Success: How Culture is Driving Human Evolution, Domesticating our Species, and Making Us Smarter (Princeton Univ. Press, 2015).

    Google Scholar 

  7. 7

    Jaeggi, A. V. & Gurven, M. Natural cooperators: food sharing in humans and other primates. Evol. Anthropol. 22, 186–195 (2015).

    Article  Google Scholar 

  8. 8

    Kramer, K. L. The evolution of human parental care and recruitment of juvenile help. Trends Ecol. Evol. 26, 533–540 (2011).

    Article  Google Scholar 

  9. 9

    Granovetters, M. The strength of weak ties. Am. J. Sociol. 78, 1360–1380 (1973).

    Article  Google Scholar 

  10. 10

    Watts, D. J. & Strogatz, S. H. Collective dynamics of ‘small-world’ networks. Nature 393, 440–442 (1998).

    CAS  Article  Google Scholar 

  11. 11

    Hruschka, D. J. Friendship: Development, Ecology, and Evolution of a Relationship (Univ. California Press, 2010).

    Google Scholar 

  12. 12

    Salali, D. S. et al. Knowledge-sharing networks in hunter-gatherers and the evolution of cumulative culture. Curr. Biol. 26, 2516–2521 (2015).

    Article  Google Scholar 

  13. 13

    Apicella, C. L., Marlowe, F. W., Fowler, J. H. & Christakis, N. A. Social networks and cooperation in hunter-gatherers. Nature 481, 497–501 (2012).

    CAS  Article  Google Scholar 

  14. 14

    Uzzi, B & Spiro, J. Collaboration and creativity: the small world problem. Am. J. Sociol. 11, 447–504 (2005).

    Article  Google Scholar 

  15. 15

    Warneken, F., Steinwender, J., Hamann, K. & Tomasello, M. Young children's planning in a collaborative problem-solving task. Cogn. Dev. 31, 48–58 (2014).

    Article  Google Scholar 

  16. 16

    Whiten, A. & Flynn, E. The transmission and evolution of experimental microcultures in groups of young children. Dev. Psychol. 46, 1694–1709 (2010).

    Article  Google Scholar 

  17. 17

    Lewis, H. M., Vinicius, L., Strods, J., Mace, R. & Migliano, A. B. High mobility explains demand sharing and enforced cooperation in egalitarian hunter-gatherers. Nat. Commun. 5, 5789 (2014).

    CAS  Article  Google Scholar 

  18. 18

    Hill, K. R., Wood, B. M., Baggio, J., Hurtado, A. M. & Boyd, R. T. Hunter-gatherer inter-band interaction rates: implications for cumulative culture. PLoS ONE 9, e102806 (2014).

    Article  Google Scholar 

  19. 19

    Dunbar, D. How Many Friends Does One Person Need? Dunbar’s Number and Other Evolutionary Quirks (Harvard Univ. Press, 2010).

    Google Scholar 

  20. 20

    Dyble, M. et al. Sex equality can explain the unique social structure of hunter-gatherer bands. Science 348, 796–798 (2015).

    CAS  Article  Google Scholar 

  21. 21

    Hill, K. R. et al. Co-residence patterns in hunter-gatherer societies show unique human social structure. Science 331, 1286–1289 (2011).

    CAS  Article  Google Scholar 

  22. 22

    Derex, M. & Boyd, R. Partial connectivity increases cultural accumulation within groups. Proc. Natl Acad. Sci. USA 113, 2982–2987 (2016).

    CAS  Article  Google Scholar 

  23. 23

    Aplin, L. M. et al. Experimentally induced innovations lead to persistent culture via conformity in wild birds. Nature 518, 538–541 (2015).

    CAS  Article  Google Scholar 

  24. 24

    Fowler, J. H., Dawes, C. T. & Christakis, N. A. Model of genetic variation in human social networks. Proc. Natl Acad. Sci. USA 106, 1720–1724 (2009).

    CAS  Article  Google Scholar 

  25. 25

    Gross, T., D’Lima, C. J. D. & Blasius, B. Epidemic dynamics on an adaptive network. Phys. Rev. Lett. 96, 208701 (2006).

    Article  Google Scholar 

  26. 26

    Macfarlan, S. J., Walker, R. S., Flinn, M. V. & Chagnon, N. A. Lethal coalitionary aggression and long-term alliance formation among Yanomamö men. Proc. Natl Acad. Sci. USA 113, 16662–16669 (2014).

    Article  Google Scholar 

  27. 27

    Burkart, J. M., Hrdy, S. B. & van Schaik, C. P. Cooperative breeding and human cognitive evolution. Evol. Anthropol. 18, 175–186 (2009).

    Article  Google Scholar 

  28. 28

    Lawler, A. Making contact. Science 348, 1072–1079 (2015).

    CAS  Article  Google Scholar 

  29. 29

    Wohlgemuth, J. & Matache, M. T. Small-world properties of Facebook group networks. Complex Syst. 23, 3 197–225 (2012).

    Google Scholar 

  30. 30

    Albert, R., Jeong, H. & Barabási, A.-L. Diameter of the World-Wide Web. Nature 401, 130–131 (1999).

    CAS  Article  Google Scholar 

  31. 31

    Minter, T. The Agta of the Northern Sierra Madre. Livelihood Strategies and Resilience Among Philippine Hunter-Gatherers. PhD thesis, Leiden Univ. (2010).

    Google Scholar 

  32. 32

    Page, A. E. et al. Reproductive trade-offs in extant hunter-gatherers suggest adaptive mechanism for the Neolithic expansion. Proc. Natl Acad. Sci. USA 113, 4694–4699 (2016).

    CAS  Article  Google Scholar 

  33. 33

    Dyble, M. et al. Multi-level social organisation facilitates food sharing among small-scale hunter-gatherers. Curr. Biol. 26, 2017–2021 (2016).

    CAS  Article  Google Scholar 

  34. 34

    Meehan, C. L., Quinlan, R. & Malcom, C. D. Cooperative breeding and maternal energy expenditure among Aka foragers. Am. J. Hum. Biol. 25, 42–57 (2013).

    Article  Google Scholar 

  35. 35

    Dagum, C. The generation and distribution of income, the Lorentz curve and the Gini ratio . Écon. Appl . 33, 327–367 (1980).

    Google Scholar 

Download references

Acknowledgements

We thank J. Lewis and R.K. Schlaepfer for help in the field. We thank R.K. Schlaepfer and RKSmedia for producing the accompanying movies, and R. Foley and J. Bertranpetit for comments. We also thank our assistants in Congo and the Philippines, as well as the Agta and BaYaka communities. This project was funded by the Leverhulme Trust grant RP2011-R-045 to A.B.M., M.G.T. and R.M. R.M. also received funding from European Research Council Advanced Grant AdG 249347. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Author information

Affiliations

Authors

Contributions

A.B.M. conceived the project, S.V. designed the motes, A.B.M., M.D., J.T., A.E.P., D.S., G.D.S., N.C. and S.V. collected data, G.D.S. provided video images from Congo and collected data on plant knowledge, J.G.-G. and V.L. performed social network analysis, J.G.-G., S.V., A.E.P., M.D., D.S., N.C., J.S., J.T., V.L., L.V and A.B.M. analysed the data, R.M. commented on the manuscript, and A.B.M., L.V., M.G.T. and V.L. wrote the paper with help from all other authors.

Corresponding author

Correspondence to A. B. Migliano.

Ethics declarations

Competing interests

The authors declare no competing interests.

Supplementary information

Supplementary Information

Supplementary Figures 1-5, Supplementary Tables 1-4. (PDF 570 kb)

Supplementary Video 1

BaYaka Pygmies from Congo Brazzaville performing the ‘Bobe’ forest spirits ritual. Bobe lasts for hours during the night. Women sing polyphonic music and play drums with children. After some time, adult men believed to be possessed by forest spirits are attracted by the singing and come into the camp to dance. The ritual is believed to be important for group cohesion. The video also shows children mimicking the adult performance of the forest spirits ritual in an unsupervised play group. Video footage shot by Gul Deniz Salali between March and July 2014. Video edited by Rodolph Schlaepfer (RKSmedia). (MP4 16943 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Migliano, A., Page, A., Gómez-Gardeñes, J. et al. Characterization of hunter-gatherer networks and implications for cumulative culture. Nat Hum Behav 1, 0043 (2017). https://doi.org/10.1038/s41562-016-0043

Download citation

Further reading

Search

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing