We investigate whether age profiles of ethnobiological knowledge development are consistent with predictions derived from life history theory about the timing of productivity and reproduction. Life history models predict complementary knowledge profiles developing across the lifespan for women and men as they experience changes in embodied capital and the needs of dependent offspring. We evaluate these predictions using an ethnobiological knowledge assessment tool developed for an off-grid pastoralist population known as Choyeros, from Baja California Sur, Mexico. Our results indicate that (...) while individuals acquire knowledge of most dangerous items and edible resources by early adulthood, knowledge of plants and animals relevant to the age and sex divided labor domains and ecologies (e.g., women’s house gardens, men’s herding activities in the wilderness) continues to develop into middle adulthood but to different degrees and at different rates for men and women. As the demands of offspring on parents accumulate with age, reproductive-aged adults continue to develop their knowledge to meet their children’s needs. After controlling for vision, our analysis indicates that many post-reproductive adults show the greatest ethnobiological knowledge. These findings extend our understanding of the evolved human life history by illustrating how changes in embodied capital and the needs of dependent offspring predict the development of men’s and women’s ethnobiological knowledge across the lifespan. (shrink)

Coall & Hertwig (C&H) bring attention to alternative accounts of grandparental investment from economics, evolutionary anthropology, psychology, and sociology, which have yet to be reconciled. We attempt to help integrate some of the disparate perspectives by expanding the scope of the evolutionary perspective, highlighting some gaps, and discussing problems with the authors' treatment of grandparents in traditional societies.

A Correction to this paper has been published: https://doi.org/10.1007/s12110-021-09399-4.

Gender differences in dishonesty and mistrust have been reported across cultures and linked to stereotypes about females being more trustworthy and trusting. Here we focus on fundamental issues of trust-based communication that may be affected by gender: the decisions whether to honestly deliver private information and whether to trust that this delivered information is honest. Using laboratory experiments that model trust-based strategic communication and response, we examined the relationship between gender, gender stereotypes, and gender discriminative lies and challenges. Drawing from (...) a student sample, we presented males and females with incentivized stereotype elicitation tasks that reveal their expectations of lies and challenges from each gender, followed by a series of strategic communication interactions within and between genders. Before interacting, both genders stereotyped females as more trustworthy and more trusting than males, in accord with cross-cultural gender differences. In best response to these stereotypes, both genders discriminately accepted or challenged messages based on the sender’s gender. However, we find no differences between males’ and females’ overall rates of lies and challenges. After learning the results of their strategic interactions, males and females revised their stereotypes about lies and challenges expected of each gender; these stereotype revisions resulted in greater predictive accuracy and less disparate gender discrimination. This suggests an important facultative feature of human trust-based communication and gender stereotyping: while the delivery and trust of private information is informed by gender stereotypes, these stereotypes are recalibrated with experience. (shrink)