Foraging complexity and the evolution of childhood

Abstract

Our species' long childhoods may have evolved as a period for learning complex foraging skills. Observational studies focusing on the development of foraging proficiency are an important line of evidence to assess this hypothesis. Currently, the literature on children's foraging is mixed, with investigators coming to inconsistent conclusions about how long it takes to become a proficient forager. In this study, we leverage published records of child and adolescent foragers from 28 societies to: (1) characterize the ontogeny of foraging returns and (2) assess how resource complexity structures variation across foraging contexts. We ?find that foraging returns increase slowly for more skill-intensive, difficult-to-extract resources (tubers and game), consistent with peak productivity attained later in adulthood. However, foraging returns for easier-to-extract resources (fruit and ?shellfish) increase rapidly during childhood, with adult levels of productivity reached by adolescence. Thus, the apparent match between the duration of childhood and the amount of time it takes to become a good forager is cross-culturally variable - it depends on the type of resources available for children to forage.

Child dietary patterns in Homo sapiens evolution

“…Though, our review included few studies drawing heavily on archeological records. Reporting bias may have been present in ethnographies observed to capture foods returned to camps such as game, while missing fruits and fish and seafoods foraged by women and children [ 97 ]. Our findings from both isotope studies as well as ethnographies supported the child consumption of aquatic animal foods in the form of small shellfish and animals found in shallow waters, pointing to the importance of this type of ASF.…”

Foraging Efficiency and the Importance of Knowledge in Pemba, Tanzania: Implications for Childhood Evolution.

“…Most recently, foraging returns have been modeled as hurdle models, modeling separately (i) the probability of success (i.e., non-zero returns) and (ii) the amount of returns (e.g. grams or calories collected) for a certain trip (Koster et al, 2020;Lew-Levy et al, 2021;McElreath and Koster, 2014;Pretelli et al, 2022b). In the case of the present study, however, the two types of foraging can be analyzed with just one of the two parts of a hurdle model.…”

“…We built on existing literature (e.g. Koster et al, 2020;Pretelli et al, 2022b) to develop a statistical model based on explicit causal assumptions, which helps us tackle the question of why humans spend so long as prereproductive individuals.…”

“…2002) may be specific to easy tasks. Indeed, Pretelli et al (2022b) find that, across cultures, more complex resources require more skill and longer acquisition times.…”

Human behaviors driving disease emergence

“…53 Indeed, children have been the presumed index case in at least three Ebola virus disease outbreaks, and frequently contact rodent reservoirs of Lassa fever and mpox through hunting. 54 Focused attention on male hunting behavior parallels early anthropological theory that attributes gender differences in hunting to an economy of scale in household economic production, whereby men must provision women who undertake child-care responsibilities and offspring. 55 This is reflected in the literature examining zoonotic exposures, which typically describe hunting as an activity of adult males, with women being responsible for butchering, preparing, and trading wild meat.…”