The Life History of Learning Subsistence Skills among Hadza and BaYaka Foragers from Tanzania and the Republic of Congo

Sheina Lew-Levy,Alyssa N Crittenden,Ibrahim A Mabulla,Michelle A Kline,Tanya Broesch,Erik J Ringen

doi:10.1007/s12110-021-09386-9

Abstract

Aspects of human life history and cognition, such as our long childhoods and extensive use of teaching, theoretically evolved to facilitate the acquisition of complex tasks. The present paper empirically examines the relationship between subsistence task difficulty and age of acquisition, rates of teaching, and rates of oblique transmission among Hadza and BaYaka foragers from Tanzania and the Republic of Congo. We further examine cross-cultural variation in how and from whom learning occurred. Learning patterns and community perceptions of task difficulty were assessed through interviews. We found no relationship between task difficulty, age of acquisition, and oblique transmission, and a weak but positive relationship between task difficulty and rates of teaching. While same-sex transmission was normative in both societies, tasks ranked as more difficult were more likely to be transmitted by men among the BaYaka, but not among the Hadza, potentially reflecting cross-cultural differences in the sexual division of subsistence and teaching labor. Further, the BaYaka were more likely to report learning via teaching, and less likely to report learning via observation, than the Hadza, possibly owing to differences in socialization practices.

Highlights

Humans have longer childhoods, extended parental provisioning, and larger brains than other members of our clade (Bogin 1997; Kaplan et al 2000; Lancaster et al 2000; Robson and Wood 2008; but see Miller et al 2019). These features may be the result of selection for longer human life spans generally (Charnov and Berrigan 1993), the Embodied Capital Hypothesis instead posits that human life history features are linked to the extensive learning required to successfully perform the subsistence activities inherent to our skill-intensive foraging niche, such as hunting, plant collecting, and plant processing (Kaplan et al 2000)
By comparing two forager populations, the present study considers how similarities and differences in subsistence and cultural practices lead to variation in social learning
Using interview data from two forager societies—the Hadza of Tanzania and the BaYaka of the Republic of Congo—this paper examined the effect of task difficulty on age of knowledge acquisition, rates of teaching, and rates of oblique transmission in the domain of subsistence

Summary

Introduction

Humans have longer childhoods, extended parental provisioning, and larger brains than other members of our clade (Bogin 1997; Kaplan et al 2000; Lancaster et al 2000; Robson and Wood 2008; but see Miller et al 2019) These features may be the result of selection for longer human life spans generally (Charnov and Berrigan 1993), the Embodied Capital Hypothesis instead posits that human life history features are linked to the extensive learning required to successfully perform the subsistence activities inherent to our skill-intensive foraging niche, such as hunting, plant collecting, and plant processing (Kaplan et al 2000). Among the Tsimane, Gidra, and Ache, for example, hunting skill peaks in mid to late adulthood and is strongly correlated with experience, independent of strength and size (Gurven et al 2006; Ohtsuka 1989; Walker et al 2002)

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Discussion

Conclusion