MOSAIC group member Anja Becker submitted a Masters thesis on breath-hydrogen test results from four department sites to study the facultative effects of market dairy access on adult lactose persistence, from data collected by Bret Beheim and MOSAIC masters student Leonie Ette at four HBEC research sites: Hokkaido, Japan; Mayangna, Nicaragua; Tsimane, Bolivia and Leipzig, Germany. With Bret Beheim, this project involved fitting a mathematical model of the reaction dynamics to the production of H2 within the large intestine, as a primary diagnosis of lactose malabsorption. This analysis is the first to date to measure the intensity of lactose intolerance within individuals, and is currently being prepared for publication.
Demographic and psychological models of artistic canonization
Art, literature, music, film, and scientific research have all been characterized as having a “canon” – a rather small set of most significant works. These works seem to have particular properties: for example, they are not only perceived as “better” or “more important” than other works, but they also tend to persist for unusually long periods of time (one might say that canonical works are “immortal”). This raises several questions: How long-lasting are canonical works, actually? What are the causes behind canonisation? Is canonisation meritocratic or is there an element of stochasticity to it? While canons seem to be a universal property of human cultures, we do not yet have definitive answers to these questions. Important research in the humanities (including computational humanities) and network science has improved our understanding of canons and cultural success at large, but the cultural-evolutionary perspective can become an important missing component that might help finding the answers to these questions. MOSAIC postdoc Oleg Sobchuk, who has experience with studying the mechanics of success in the arts (Morin & Sobchuk 2020; Sobchuk & Tinits 2020), is leading an analysis of cultural-evolutionary theories of canonization. Our goal is to develop a general causal understanding of the canon, and to assess the extent to which canonization is affected by idiosyncratic and stochastic effects. We will develop statistical models of canonisation and will test them using large datasets, such as the digital collections of literature, paintings, scientific papers, games, and the like. Also, we intend to critically assess the possible “taphonomic” biases that such datasets may contain – and whether these biases can emerge as a result of the canonisation process itself. Related recent work:
- Morin O, Sobchuk O (2021), The shortlist effect: Nestedness contributions as a tool to explain cultural success, Evolutionary Human Sciences, 3: e51.
- Sobchuk O, Tinits P (2020), Cultural attraction in film evolution: The case of anachronies, Journal of Cognition and Culture, 20(3-4): 218–237.
The effect of demographic structure on the rate of acculturation
Using longitudinal THLHP records on reproduction and mortality, we are currently studying the extent to which indigenous language shifts towards Spanish in the face of rapid market integration are driven by demographic disparities between speakers and non-speakers (lead: Riana Minocher), measured as differences in age-specific fertility, in inter-birth intervals, in mortality, and systematic trends in parent-offspring language transmission. This project won Best Student Presentation at the Cultural Evolution Society Conference in 2021. We are also participating on a similar analysis led by the Comparative Behavioral Ecology group (lead author Arianna Dalzero) studying the demographic details of cross-cousin marriage among the Tsimane using the life history dataset curated by MOSAIC.
Settlement strategy: Trade-offs between building, moving, and saving
As part of her doctoral research Natalia Fedorova has been working on a optimality model of housing investment. In order to improve our understanding of human-environment interactions, it is necessary to know when households choose to invest in their dwellings, particularly when capital can be directed in other directions. Investments in housing have implications for mobility and future portfolio decisions, building up the constructed landscape we live in. However, they have rarely been the focus of modeling or empirical work in evolutionary anthropology.
Using stochastic dynamic programming, which allows us to track optimal strategies over time, NF has modeled the trade-offs between investing in housing, moving, and saving. NF has also conducted fieldwork in the ger districts of Ulaanbaatar, the capital of Mongolia. The ger districts provide an excellent case study for housing investments as they are areas of the city where households predominantly build their own housing, and crucially, do so in two distinct forms. Households build gers, circular felt dwellings that are mobile, and bashins, western-style houses built of brick, wood, and other industrially produced materials. The optimality model is used to analyze and understand the situation in Ulaanbaatar, with approximate bayesian computation being used in this generative inference framework to interface model and data. The manuscript is currently in preparation.