High fidelity: How forager myth transmission rules scaffold faithful transmission of accumulated cultural knowledge

– by Michelle Scalise Sugiyama

For most of our species’ existence, culturally shared knowledge has been stored in memory and transmitted orally. This presents an impediment to the emergence of cumulative culture: how to encode, retrieve, and transmit accumulated knowledge in a portable, readily accessible format that resists corruption. Ethnologists have long observed that, in hunter-gatherer cultures, narrative is used for this purpose. Widely characterized as teachings by their Indigenous proprietors, forager oral traditions are known to encode a broad range of ecological knowledge. However, this strategy substitutes one memorization task for another: if a story is misremembered, the knowledge it encodes faces the same fate. Thus, the effectiveness of storytelling as an information management system hinges on the production of high-fidelity copies from telling to telling, begging the question of how this is accomplished.

Research on the formal properties of oral narrative–both prose and verse–shows that these traditions are maintained through the application of multiple mnemonic strategies, many of which exploit cognitive biases. Formal and genre constraints further facilitate recall by limiting the performer’s options as a tale or poem is being unraveled from memory. To take a modern example, the coarse subject matter, humorous tone, laconic style, distinctive meter, and AABBA rhyme scheme of limerick sharply delimit the sentiment, syllables, and words that can follow the line, “There once was a man from Nantucket.” However, research indicates that exploitation of cognitive biases does not guarantee full retention. A series of four experiments using folk stories found that subjects recalled minimally counterintuitive items better than mundane items in the stories. If these findings are representative of oral story transmission in general, we would expect “mundane” content (i.e., generalizable knowledge) to be lost over time, but this prediction is belied by the plethora of ecological knowledge encoded in forager narrative. How do oral cultures manage this?

Our study tested the hypothesis that, to meet the challenge of high-fidelity replication, foraging peoples have developed myth transmission rules. Our inspiration was the following description of Klamath and Modoc storytelling:

“Myth narration occurred principally on winter nights and informal sanctions prohibited myth narration at other times. For example, the Modoc believed that telling myths during the day would cause one to be bitten by a rattlesnake. . . . Klamath myth narration ideally ceased at the end of winter. . . . telling myths after this time would purportedly delay the long-awaited arrival of spring. . . . Only adults were permitted to narrate. . . . However, participation as a listener was unrestricted and generally included the entire winter household. . . . Myths preferably were not mixed with other oral tradition forms. . . . Narrators were not permitted to deviate greatly from local versions. If narrators diverged excessively, listeners would interrupt and engage in debate until the correct version was decided upon. (306-307)”

These restrictions limit myth narration to winter nights, confining transmission to large blocks of leisure time when people are gathered together. This practice minimizes distractions, enabling listeners to give full attention to the story, and “copies” the story to several minds simultaneously. Adult-only narration increases the probability that myths are told by persons who know them thoroughly, while mixed-age audience composition ensures that older generations are present to check for accuracy and younger generations are present to learn the myths. Finally, fear of negative sanctions discourages people from breaking these rules. Collectively, these restrictions increase the chances that the “right” version of a myth—and the knowledge it encodes–gets copied to the next generation.

To test our hypothesis, we searched the forager ethnographic record for descriptions of oral storytelling, which we analyzed for the presence of eight rule types: (1) transmission by the most proficient storytellers (2) under low-distraction conditions with (3) multiple individuals and (4) generations in attendance, and the application of measures that (5) prevent, identify, and/or correct mistakes, (6) maintain audience attention, (7) negatively sanction rule violations and/or (8) incentivize rule compliance. Although our sample was heavily biased toward North American foragers, we found descriptions for 80 different cultures, distributed across six continents and diverse biomes.

All of the predicted rule types were present on at least three continents, and seven types were present on at least four. Myth recitation was largely the prerogative of older adults and preferentially occurred during periods of low economic activity. Most tellings occurred in the context of formal or informal social gatherings, with mixed-age audiences the norm. Rules regulating narrator performance occurred in 50 cultures, and included the use of prompting (e.g., call-and-response), repetition, song, and other forms of ostensive communication to engage and sustain audience attention. Listeners, in turn, were commonly expected to signal periodically that they were still awake, and to interrupt and correct the narrator if mistakes were made. Evidence of sanctions was limited to Africa and the Americas, and consisted largely of a belief that misfortune would follow rule transgressions.

These findings point to additional factors at play in the emergence of cumulative culture. Symbolic behaviors (e.g., myth, song, dance, visual art, games, names) and rules surrounding their performance have been largely unexplored as systems that support high-fidelity encoding and transmission of generalizable knowledge. Re-conceptualizing these behaviors as information technologies may help us better understand how evolved cognitive capacities, ecological constraints, and human inventions interact to produce the ratchets that make cumulative culture possible.

Read the original article: Scalise Sugiyama, M., & Reilly, K.J. (in press). Cross-cultural forager myth transmission rules: implications for the emergence of cumulative culture. Evolution & Human Behavior.