Rates of ecological knowledge learning in Pemba, Tanzania: Implications for childhood evolution

Abstract

Humans live in diverse, complex niches where survival and reproduction are conditional on the acquisition of knowledge. Humans also have long childhoods, spending more than a decade before they become net producers. Whether the time needed to learn has been a selective force in the evolution of long human childhood is unclear, because there is little comparative data on the growth of ecological knowledge throughout childhood. We measured ecological knowledge at different ages in Pemba, Zanzibar (TZ), interviewing 93 children and teenagers between 4 and 26 years. We developed Bayesian latent-trait models to estimate individual knowledge and its association with age, activities, household family structure, and education. In the studied population, children learn during the whole pre-reproductive period, but at varying rates, with fastest increases in young children. Sex differences appear during middle childhood and are mediated by participation in different activities. In addition to providing a detailed empirical investigation of the relationship between knowledge acquisition and childhood, this study develops and documents computational improvements to the modeling of knowledge development.

Foraging and the importance of knowledge in Pemba, Tanzania: implications for childhood evolution

“…Our results indicate that childhood is a not time for idling, or just a by-product of other selective pressures, as suggested by early hypotheses [8]. On the contrary, we show that childhood is an active period during which individuals engage, sometimes very successfully, in a variety of activities, which promotes knowledge acquisition [32]. Learning can still be an important reason for the evolution of childhood, however, we point to the fact that the pathways by which knowledge impacts results, and fitness down the line, can be more complex than expected and implicate the involvement of other individuals.…”

“…Other aspects of the models include the estimation of ecological knowledge using an Item Response Theory model (see Pretelli et al [32] for more details on this tool) and the estimation of missing data for knowledge, height and grip strength according to each individual’s age and sex. Note that even though data points relative to individuals who are missing certain measurements provide no information to the model concerning the specific inference for knowledge, height or grip strength, including these data points still improve the model fit and estimation of the other parameters, informed by the non-missing parts of the data (see electronic supplementary material, S3.2).…”

“…Ecological knowledge was measured from a combination of three parts of the survey: answers to a freelist question, where individuals were asked to name all living creatures that could be encountered in and around the village, forest, or beach and sea; answers to 50 ecological knowledge questions; identification of organisms shown in 27 pictures. For more information on this method, see Pretelli et al [32].…”

Insights into canine rabies vaccination Disparities in Sierra Leone: A cross-sectional household study

“…It offered an advancement over previous studies on rabies that modelled rabies knowledge or understanding using observed data [ 52 ]. This is because knowledge is always latent and can never be fully measured [ 53 ]. Similar approaches have been used in diverse fields to target latent knowledge or ability questions [ 53 , 54 ].…”

“…This is because knowledge is always latent and can never be fully measured [ 53 ]. Similar approaches have been used in diverse fields to target latent knowledge or ability questions [ 53 , 54 ]. Our results suggested that latent understanding (dog owners’ overall knowledge of the disease) was positively associated with dog vaccination and tertiary-level education, consistent with a recent report from Nigeria [ 36 ].…”