Hyenas and Triadic Closure
The Triadic Closure theory claims that if two people in a social network have a friend in common, they are likely to become friends themselves at some point. It makes sense that humans prefer to seek companionship among those likely to share similar interests and personalities. Social media provides particularly strong evidence for the triadic closure theory among humans, as we can observe people growing their connections by friending the people who already share a mutual relation with them. Platforms like Facebook utilize triadic closure theory by basing their linking suggestions off of people the individual already knows.
However, triadic closure doesn’t just apply to human social networks. This phenomenon has been observed at work among the animal kingdom, particularly hyenas. Scientists at the University of Tennessee studied clans of hyenas for 20 years, and found that the principal way hyenas grew their clans was through triadic closure.
Hyena clans were often quite large, including over 100 hyenas, reflecting the 22 year life span of the animal. Scientists observed that every individual hyena did not try to form bonds with every single hyena in the clan. A particular hyena might rely on a close group of trusted friends to hunt together and survive. When the predator looks to increase his network, he usually chooses to bond with a hyena that shares some maternal or paternal kin with him. From an evolutionary standpoint, this makes sense. A hyena that is already somewhat familiar is less likely to harm him than an absolute stranger.
This study performed by the University of Tennessee was one of the largest studies of social network dynamics in a nonhuman species. Researchers collected over 50,0000 observations of hyena social interactions over the twenty year research period, and while there were other influences on friend formations, such as social rank and environmental effects, the evidence overwhelmingly indicated that triadic closure was the most important factor in how individual hyenas sought out and formed social bonds.
It is interesting that triadic closure is a principle that spans the divide between human and animal behavior. Although humans can be argued to be far more socially sophisticated than hyenas, the base instincts present are all the same. I wonder what other similarities there are between how humans and animals form social connections and interact in group settings.
https://www.deccanherald.com/content/500949/hyenas-their-own-facebook-algorithm.html
https://phys.org/news/2015-05-friends-friendseven-hyena.html