The evolution of fire may have had major social impacts, as well as transforming our diet, according to new research.
Research among the Bushmen of the Kalahari has found sitting around a campfire at night enables conversations, storytelling, and social bonding that rarely happens during daylight.
Study author Dr Polly Wiessner, professor of anthropology at the University of Utah , analysed the content of 174 recorded or documented day and nighttime conversations among the Bushmen, as well as 68 other translated texts.
“I found this really fascinating difference between conversations by firelight and conversations in the day,” says Wiessner, whose research is published this week inProceedings of the National Academy of Sciences.
While daytime talk tended to focus on economic matters and gossip, at night around the campfire, the conversation shifted away from the day-to-day tensions and towards singing, dancing, religious ceremonies and storytelling, and chat about common acquaintances.
“The day is harsh, you see the realities, you see the facial expressions, there’s work to be done, and there’s social regulation, and at night people kind of mellow out,” Wiessner says.
While evolutionary study of the impact of fire has long focused on the physiological changes associated with cooking of food, Wiessner was more interested in its social impact.
“The day is productive time for hunting and gathering and the firelight changed our circadian rhythm, so we stayed awake much longer and it gave a whole new time and space, and it was a time when no work could be done,” she says.
“I think it had an impact on our cognitive evolution; the stories are told in wonderful language, perhaps increasing linguistic skills and the imagination . . . when you’re out in the dark by a fire, so many of the stimuli are shut out and your imagination then takes off.”
The conversations also seem to serve an important social function, with discussion of far-flung acquaintances both alive and dead, that can serve to reinforce that broader social network, says Wiessner.
“A bushman with widespread networks, they see this as their broader community but actually these aren’t contiguous in space and sometimes even include people you don’t know very well.”
Impact of artificial light
The development of artificial lighting may have pushed the campfire out of our lives, but Wiessner says we still sometimes try to recreate that atmosphere.
“Even in our society, we love our fireplaces, in our restaurants we have candlelight, we often do a lot to change our environment to bring about the mood that stimulates intimacy, bonding, and imagination.”
However the development of artificial lighting and computers also means that those night-time hours when, in the past we would have been engaged in social bonding, we now often see those hours as an extension of daylight work time.
“For many people now artificial light has turned what were social hours into really productive hours,” says Wiessner.
“We sit there at the computer, we write, we feel we can continue to get work done, and we don’t get the social work done, we don’t spend nearly as much time with people, so the question is, when artificial light turns social time into productive time, what happens?”