A fantastic analysis of fireside conversations among Ju/’hoansi Bushmen collected over the course of four decades (1970s-2000s) was recently published by Polly Wiessner in PNAS Early Edition (“Embers of society: Firelight talk among the Ju/’hoansi Bushmen“—thanks to Daniel Lende & Michaela Howells for alerting me to this piece).
Several highlights make me want to find a grad student who wants to do fire research so we can expand upon our current lab-based & local study (& right before I “went to press” with this, I was giving a rundown to my virtual writing group & got a great field site suggestion from Cara Ocobock–apply to Bama & I will tell you more!).
…little is known about what transpired when firelight extended the day, creating effective time for social activities that did not conflict with productive time for subsistence…Night talk plays an important role in evoking higher orders of theory of mind via the imagination, conveying attributes of people in broad networks (virtual communities), and transmitting the “big picture” of cultural institutions that generate regularity of behavior, cooperation, and trust at the regional level. [from abstract, pg. 1]
Day talk centered on practicalities and sanctioning gossip; firelit activities centered on conversations that evoked the imagination, helped people remember and understand others in their external networks, healed rifts of the day, and conveyed information about cultural institutions that generate regularity of behavior and corresponding trust. [from “Significance,” pg. 1]
Wiessner plotted the location of protagonists in stories told around the fireside (except for those involving anthropologists! LOL). I wonder about the practicality of doing something like this with contemporary campers. Ethnography of one of those campgrounds where people rent a site & live there for extended periods, coming back year after year. Does the evening campfire have the same effect, even when they can retreat to their RVs? What is the effect of sitting around a fire with your smartphone in your hand? And, yes, I’m guilty of this too, checking out in the midst of a social circle (I know, shame on me).
In most hunter-gatherer societies, firelit hours drew aggregations of individuals who were out foraging by day and provided time for ventures into such virtual communities, whether human or supernatural, via stories and ritual. Stories conveyed unifying cosmologies and charters for rules and rites governing behavior. These stories also conveyed information about the nature of individuals in the present and recent past, their experiences and feelings, as well as factual knowledge about long-distance networks, kinship, and land tenure. Stories told by firelight put listeners on the same emotional wavelength, elicited understanding, trust, and sympathy, and built positive reputations for qualities like humor, congeniality, and innovation. 
Here, specifically, are some research suggestions my lab is equipped to take on now (seriously, grad applications are being accepted):
…further research needs to be done on the physiological effects of different levels of firelight, including hormonal states and moods. Experimental work on the impact of body language and facial expressions by day and by night also might further understanding of why firelight mellows, bonds, and releases inhibitions in such a way as to facilitate journeys into imagined communities…the topics of night conversations in dyads or smaller groups need investigation…night conversation merits study to see if basic tendencies hold…