Cultural complexity and demography: The case of folktales

Abstract

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Cultural selection and biased transformation: two dynamics of cultural evolution

“…Perhaps those instances where population size does seem to determine the rate of cultural evolution, mostly relating to technology [61,64], can be taken as evidence of cultural selection operating in that domain. Instances where population size does not seem to affect the rate of cultural evolution, as observed for example for folk tales [65], can be taken as evidence of biased transformation operating in that domain. However, this requires overcoming empirical issues surrounding estimates of population size and structure [60], measures which may not always be available or reliable.…”

A systems approach to cultural evolution

“…The structure involves a central 'main-axis' with stepwise modification as in the unidirectional example above, but each trait on the main-axis can also be modified in a separate direction, to create 'toolkit innovations', and traits on the main-axis can be combined. While this sequential and combinatorial structure may be apt for understanding the evolution of (some aspects of) technological evolution, it seems less apt for characterising the opportunistic and creative processes involved in myth and storytelling (Morin, 2016;Acerbi et al, 2017), ritual and religions (Whitehouse, 2000), or social norms and institutions (Sperber, 1996;Bowles, 2004).…”

Compositional structure can emerge without generational transmission

“…Going beyond language evolution and change, this conclusion has already influenced work on a wide range of human behaviors. For example, compressibility pressures during cross-generational transmission have been implied to play a role in explaining cross-cultural differences in folk tale complexity (Acerbi, Kendal, & Tehrani, 2017), musical universals (Trehub, 2015), and the propagation and stabilization of behavioral conventions (Scott-Phillips, 2017).…”