Category: evolution

Facebook and Adaptation?

There are a myriad of reasons behind our use of social media; we inform and are informed, we present ourselves and we scrutinise the presentations of others, and, importantly, we make and maintain reciprocal and unidirectional connections with others.

From an evolutionary perspective, it could be said that, in managing our online reputations, we gain adaptive advantages. In fact, belonging to a social grouping is, at times, as important as our need for food, shelter and sex. Within the protective pod, herd or tribe our chances of survival and reproductive success increase. Our social support network buffers against depression and anxiety and, indeed, connection to the group has been shown to not only bolster survival, but increase thriving. Long before the advent of social media, we ‘liked’ and ‘friended’ people. So, it could be argued that Facebook just takes advantage of our innate, primordial need for the social.

In 1992, British anthropologist Robin Dunbar, suggested that neocortical processing capacity limited the number of people with whom we could maintain inter-personal relationships. In other words, with the limited cognitive processing power of our puny brains, we had to limit the size of our social networks. By examining the size of the social networks of apes and measuring the size of their brains, Dunbar proposed that because of our big old brains we could maintain stable social networks of 148 warm bodies, rounded up to 150…..voilà, “The Dunbar Number”.

[Update 080216: Dunbar et al, 2015 examined Facebook and Twitter data-sets and confirmed that sizes of networks and mean frequencies of contact closely match observed values from offline networks.

Not everyone agrees with the good doctors’ theory, with researchers at Harvard, for example, finding that even prolific socialisers often only have a small group of friends with whom they can discuss important matters. Bernard and Killworth of “small world” fame, have put forward estimates which almost double the “Dunbar Number” (290) and some sociologists make a distinction between one’s social “core” and our wider social network.

At a recent lecture, about 200 first year psychology students were asked, by show of hands (scientific?), how many friends each had on Facebook. The average participant, in this rigorous study, admitted to having between 300 and 400; some, at the tail-end of the graph admitting to numbers exceeding 500. Aside from this study (dripping with scientific rigour), there is little doubt that Facebook increases the size of our social network, but this makes sense if we think of Dunbar’s hypothesis…acquiring new “friends” online is cognitively frictionless and maintaining Facebook Connectedness (Grieve et al, 2013) is mentally, almost, free of charge.

Interestingly, Cameron Marlow and his associates, at Facebook, have found that, on average, the number of “friends” in a social network is…wait for it…calling Dr. Dunbar….120! More interestingly still, the authors found that Facebook users usually interact with a small, stable group. Corroborating what the researchers at Harvard had found, that generally, men with 120 friends actively interact with 7 people and women interact with 10. And what about those who have 500 Facebook friends? Well, the men leave comments for 17 friends, women for 26, men communicate with 10 people, and women with 16. So, our active, core social network remains small and stable, but it seems that we passively track a much larger, but casual system of social relations.

So, when we post content to Facebook are we not being extraordinarily adaptive? Are we not moving beyond our small, stable “core”? Are we not advertising our wares outside our “Dunbar Number”? Have we not evolved and become fitter and more efficient? Our ancestors had to work considerably harder than us, physically and mentally, to maintain relationships, but in our digitised world, metaphorically picking fleas out of our friends fur takes a little bit less mental computation.
Grieve, R., Indian, M., Witteveen, K., Tolan, G., & Marrington, J. (2013). Face-to-face or Facebook: Can social connectedness be derived online? Computers in human behaviour, 29, 3. 604-609.
Carl Bialik (16 November 2007). “Sorry, You May Have Gone Over Your Limit Of Network Friends”. The Wall Street Journal Online. Retrieved 13th Nov 2015.