We gather around campfires and share stories, keeping the darkness at bay to draw each other into worlds of ghosts and monsters, to immerse ourselves in the past and future. Communing around a fire entwines humanity in a yarn stretching back to our hominin ancestors, who stoked these embers of storytelling. And those nightly fires could have been the hearths from which early language emerged.
Hominins began taming fire around 1.5 million years ago, and by 400,000 years ago hearths were more common as our ancestors used fire to chase away darkness at night. The glowing little world that a fire creates around itself, painting cave walls and the faces of our companions in warm hues and lively shadows, calls us in to lean closely and listen. This environment may have ignited a shift from our ancestors communicating about the world around them, to narrating things they could not see. Communication moved from something like the gestures great apes use today, like chest-beating or baring their teeth, toward a simple proto-language that was a step toward modern language, according to an anthropologist and a primatologist who published their theory last month.
Read more: “Human Ancestors Were Using Fire Earlier Than Previously Thought”
“Storytelling really is core to human evolution,” said Robin Dunbar, an emeritus professor of evolutionary psychology at the University of Oxford, who was not involved in the new study but who studies the behavioral, cognitive, and neuroendocrinological mechanisms that underpin social bonding in primates and early humans.
While we can’t know for sure what tales were told around crackling fires hundreds of thousands of years ago, modern day hunter-gatherer communities can illuminate what those ancient nights may have looked like. Anthropologist Pauline Wiessner worked for decades in Namibia and Botswana among Ju/’hoansi communities, whose nighttime conversations differ dramatically from daytime exchanges. Everyday information and gossip are shared during daylight, but at night, people spin yarns about time travel, humans turning into animals, the moon and the stars, and ghosts and demons.
So what is it about fire that makes us want to tell stories?
The dim luminance of firelight might have something to do with it. Since it’s difficult to see in the low light, shifting to spoken words over gestures has advantages. Low light can also loosen inhibitions around communication, while enhancing storytelling effect. “Body language is dimmed by firelight and awareness of self and others is reduced,” wrote Wiessner, who did not collaborate on the new research, in a 2014 paper about the Ju/’hoansi. “Facial expressions—flickering with the flames—are either softened, or in the case of fear or anguish, accentuated.”
The new paper, written by University of Saint Andrews primatologist Catherine Hobaiter and Dartmouth University anthropologist Nathaniel Dominy, takes these concepts a step further, interpreting the fireside as a social niche unique to prehistoric humans and a cradle of human language—an “integrated sensory experience” that intermingled light, color, and rhythm.
Almost completely at the red end of the spectrum, firelight has nearly no blue wavelengths. This type of light partially suppresses melatonin, staving off sleep, but as it dies down, firelight “falls squarely in the optimal range for sleep preparation… with glowing embers providing the best light of all,” Hobaiter and Dominy wrote. This would have extended waking hours without diminishing sleep quality, resulting in a psychological wind down at the end of the day as the fire smouldered.
Firelight also dispenses a large dose of infrared wavelengths. Research suggests true infrared light provides metabolic benefits, stimulating energy production in our cells, and helping our bodies process nutrients more efficiently. Around a fire, that might help humans digest food more effectively, or offset the metabolic costs of complicated cognitive processing, said Hobaiter. This dovetails with an existing theory suggesting human brains evolved to grow larger, making advanced cognition possible, partly because cooking food over fire unlocked more calories.
Fire’s rhythmic flickering also creates a hypnotic, mesmerizing effect shared among those huddled in its glow. Shared rhythmic activity, such as making music or dancing together, synchronizes our brain waves and fosters social connection. Flickering light can also cause photic driving: Our neurons fire in synchrony with the flux of the flame. Around a single communal flickering light, the shared sense of rhythm could synchronize our minds.
“Part of what might instill this deep sense of social connection and social bonding that happens around a fire could be that fire is a point of shared focal, social symmetry—much in the way that when we’re dancing to music together we’ve got a beat,” said Hobaiter. “We’re quite literally ending up on the same wavelength.”
This environment would have been ideal for speaking rather than gesturing, the authors argue, priming humans to use spoken language to communicate beyond immediate experiences, and soar into unseen possibilities, times, and worlds. “You can start to go from ‘what did we do today’ and ‘what will we do tomorrow,’ to ‘what did we do this time last year,’ ‘where do we need to go in a few weeks’ time,’ to then starting to think about these bigger picture, more abstract concepts,” said Hobaiter. This progression would have likely been incremental, she added, baby steps from gestures toward something like pantomime to express more abstract ideas, and eventually from simple vocalizations to more articulated words.
Other theories place the origin of language much later than the origins of taming fire, explained Ian Tattersall, Curator Emeritus of Human Origins at the American Museum of Natural History who studies the evolution of human cognition, and who wasn’t involved in Hobaiter’s and Dominy’s research. For language to emerge, early humans would have needed brains capable of symbolic thought, an anatomical development step that he suggests happened around 200,000 years ago. Tattersall noted that the earliest evidence of symbolic thought occurred at the advent of art and artifacts that symbolically represented things in the environment, around 100,000 years ago. He said he sees language as an ability that evolved alongside that cognitive leap.
“Language is a radically different kind of thing from anything that preceded it, and it had to do not only with communication, but with how hominins perceived the world,” Tattersall said.
According to Tattersall, the first control of fire between 1.5 million and 400,000 years ago would have been too early for hominins to have the biological brain capability, and the proven ability in the archaeological record, of symbolic thought necessary to develop language.
Fire is important to human social evolution, and storytelling does go hand in hand with sitting around a fire, Tattersall said, but he claimed that language needed to have existed already before fireside stories could be told—not that taming fire and taming language necessarily emerged in tandem. “I don’t think language was around far back enough to have been a major influence on early sitting around campfires,” Tattersall added. “But I think that once language was available, it completely changed the experience of sitting around a fire.”
Wiessner doesn’t characterize fireside storytelling as the sole catalyst for human language either, as Hobaiter and Dominy propose, but concedes it may have been crucial. Firelight represented an important niche that shaped language evolution and other uniquely human social attributes, according to Wiessner.
By firelight, community members not only share information and strengthen social bonds, continuedWiessner, but they also sense what others are thinking and feeling through stories. Exposure to the range of others’ perspectives and feelings can foster theory of mind and empathy.
“I think the pull [of fire] on language would have been huge here,” said Wiessner. “Having people come together at night, and having these hours of time to interact, probably made a big difference. A really strong force pulling language.”
While the idea that fire facilitated storytelling and language evolution isn’t completely new, said Dunbar, the new paper explores physiological sensitivities to firelight, and the synchrony it may engender, in interesting ways. Like with laughter or dance, synchrony is extremely important to us as a species. “[In storytelling] you have the audience all taking part in a synchronized way,” said Dunbar. “It creates this wave of bonding and warmth that goes throughout the whole circle—it’s magic.”
Of course, the advent of artificial light dramatically changed humanity’s nighttime rituals, turning darker hours into economically productive time instead of just story time. “The day then ends with the flip of a switch, without taking the time to revisit, explore, ponder, and repair relationships, or let the issues of the day fade with the embers,” wrote Wiessner.
But even today, humans ensconced in the comforts of modern technology continue to seek out time by the fire.
“Fire is at the heart of so many of our social rituals,” said Hobaiter, from gathering near a fireplace in winter to sitting around a bonfire in summer. “This combination of the properties of light, of the social niche that this creates, and of the firelight itself synchronizing our brain activity or behavior with each other, is what’s mediating this sense of social connection.”
The way we fall into a reverie beside a fire lives deep in our bodies, despite layers of modernity. The rhythm of a good story harmonizes with the rhythm of a flickering fire, synchronizing with our brains, integral like our heartbeats. We stay up just a bit later conjuring up what came before us, and what will come after us. A torch passed down over hundreds of thousands of years, our human story blazes in the heart of the communal fire. 
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