The life history of human foraging: Cross-cultural and individual variation

Abstract

Human adaptation depends on the integration of slow life history, complex production skills, and extensive sociality. Refining and testing models of the evolution of human life history and cultural learning benefit from increasingly accurate measurement of knowledge, skills, and rates of production with age. We pursue this goal by inferring hunters’ increases and declines of skill from approximately 23,000 hunting records generated by more than 1800 individuals at 40 locations. The data reveal an average age of peak productivity between 30 and 35 years of age, although high skill is maintained throughout much of adulthood. In addition, there is substantial variation both among individuals and sites. Within study sites, variation among individuals depends more on heterogeneity in rates of decline than in rates of increase. This analysis sharpens questions about the coevolution of human life history and cultural adaptation.

Productivity loss associated with physical impairment in a contemporary small-scale subsistence population

“…In comparative cross-species perspective, modern human life histories are characterized by delayed peak foraging efficiency (e.g. (Kaplan 1994; Kaplan 1997; Koster et al 2020; Walker et al 2002)), complex cooperative strategies to produce and rear altricial, slow-growing offspring (e.g. (Hawkes 2003; Kaplan and Hill 1985; Richerson and Boyd 2008; Wood and Marlowe 2013)), low adult mortality rate (e.g.…”

“…Human hunter-gatherers have lower adult mortality than chimpanzees and a significant post-reproductive lifespan (Gurven and Kaplan 2007; Hill et al 2007; Kaplan et al 2010; Kaplan et al 2000; Wood et al 2017), which generates ample opportunity for incident degenerative disease and dysfunction (Finch 2010). Evidence of greater dietary reliance by hominins on difficult-to-acquire resources including hunted game at least 2 mya (Aiello and Wheeler 1995; Antón et al 2014; Thompson et al 2019; Ungar 2012) suggests delayed peak skill acquisition in adulthood (Gurven et al 2006; Kaplan et al 2000; Koster et al 2019; Walker et al 2002), possibly when senescence was already underway. Functional disability of degenerative origin may hinder hominin foraging in costly ways.…”

Productivity loss associated with functional disability in a contemporary small-scale subsistence population

“…In comparative cross-species perspective, modern human life histories are characterized by delayed peak foraging efficiency (e.g. Kaplan, 1994 ; Kaplan, 1997 ; Koster et al, 2020 ; Walker et al, 2002 ), complex cooperative strategies to produce and rear altricial, slow-growing offspring (e.g. Hawkes, 2003 ; Kaplan et al, 1985 ; Richerson and Boyd, 2008 ; Wood and Marlowe, 2013 ), low adult mortality rate (e.g.…”

“…Human hunter-gatherers have lower adult mortality than chimpanzees and a significant post-reproductive lifespan ( Gurven and Kaplan, 2007 ; Hill et al, 2007 ; Kaplan et al, 2010 ; Kaplan et al, 2000 ; Wood et al, 2017 ), which generates ample opportunity for incident degenerative disease and dysfunction ( Finch, 2010 ). Evidence of greater dietary reliance by hominins on difficult-to-acquire resources including hunted game at least two mya ( Aiello and Wheeler, 1995 ; Antón et al, 2014 ; Thompson et al, 2019 ; Ungar, 2012 ) suggests delayed peak skill acquisition in adulthood ( Gurven et al, 2006 ; Kaplan et al, 2000 ; Koster et al, 2020 ; Walker et al, 2002 ), possibly when senescence was already underway. Functional disability of degenerative origin may hinder hominin foraging in costly ways.…”

Do people manage climate risk through long-distance relationships?

“…Finally, as with many anthropological investigations, the power of this study was fairly low because of a quite modest sample size (n=119). This limitation can potentially be overcome by pooling data across study populations via cross-cultural comparative work (e.g., Koster et al, 2020).…”