The Hearthside Effect: Cooked Nutrition as an Underexamined Driver of Cognitive Evolution in Settlement-Adjacent Species

This paper proposes the “Hearthside Effect”: the hypothesis that sustained, multigenerational access to cooked and processed human food has served as a significant but largely overlooked nutritional driver of increased cognitive flexibility in settlement-adjacent species. While Richard Wrangham’s cooking hypothesis has established the role of fire-processed food in enabling human brain expansion through improved caloric bioavailability and metabolic reallocation, its implications for non-human species sharing those nutritional environments remain underexplored. Species such as dogs, pigs, commensal rodents, corvids, and raccoons — and to a lesser extent cats — have lived for millennia in close proximity to human hearths, consuming diets richer in bioavailable calories, starches, and fats than their wild counterparts. Drawing on established mechanisms including enhanced nutritional bioavailability, epigenetic inheritance, gut-brain axis modulation, and genetic adaptations (such as AMY2B gene amplification in dogs), we suggest that this shared nutritional niche may have contributed to the enhanced problem-solving capacities observed in many human-associated animals. The hypothesis yields a clear, testable prediction: settlement-adjacent populations of these species should exhibit greater cognitive flexibility on novel tasks than isolated populations of the same or closely related species. This essay presents no new empirical data. It is offered as a philosophical hypothesis — a reasoned extension of the accepted human cooking hypothesis — intended to stimulate empirical research in evolutionary cognition, domestication studies, and philosophy of biology.