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Recent work suggests combining physical activity with cognitive tasks may have been critical to human evolution and may be beneficial to human brain health today. These combined tasks are key elements of foraging, a lifestyle employed by human ancestors for over 2 My. However, it is unclear whether cognitive engagement during foraging-like tasks impacts endurance, and therefore foraging performance, and whether cognitive adaptations may mitigate these effects. We tested the hypothesis that cognitive engagement during endurance walking increases perceived physical effort without influencing physiological responses, and that enhanced cognition mitigates these effects. Thirty healthy adults (n_female= 17; aged 18 to 53) underwent nonlocomotor cognitive testing and completed two separate randomized endurance tests: one without (Ex) and one with simultaneous executive function tasks (ExCog). For each condition, participants walked on a treadmill for up to 30-min while physiological responses were recorded, and perception of effort was assessed every 2-min using Borg’s rating of perceived exertion (RPE) scale. During the ExCog condition, RPE was significantly greater (P= 0.005), while energy expenditure was significantly lower (P= 0.008) compared to the Ex condition. Additionally, we observed significant interactions between cognitive abilities and endurance performance—for example, individuals with greater visuospatial abilities experienced a smaller increase in perceived effort (RPE) in the ExCog condition compared to the Ex condition (FDRP= 0.039). These results indicate that cognitive demands and cognitive abilities associated with foraging distinctly influence endurance, suggesting that evolutionary shifts in human cognitive capacities may have relaxed constraints on endurance foraging performance. 

Human evolutionary ecology stands to benefit by integrating theory and methods developed in movement ecology, and in turn, to make contributions to the broader field of movement ecology by leveraging our species' distinct attributes. In this paper, we review data and evolutionary models suggesting that major changes in socio-spatial behavior accompanied the evolution of language. To illustrate and explore these issues, we present a comparison of GPS measures of the socio-spatial behavior of Hadza hunter-gatherers of northern Tanzania to those of olive baboons (Papio anubis), a comparatively small-brained primate that is also savanna-adapted. While standard spatial metrics show modest differences, measures of spatial diversity, landscape exploration, and spatiotemporal displacement between individuals differ markedly. Groups of Hadza foragers rapidly accumulate a vast, diverse knowledge pool about places and things over the horizon, contrasting with the baboon's narrower and more homogeneous pool of ecological information. The larger and more complex socio-spatial world illustrated by the Hadza is one where heightened cognitive abilities for spatial and episodic memory, navigation, perspective taking, and communication about things beyond the here and now all have clear value. 

Abstract Low total energy expenditure (TEE, MJ/d) has been a hypothesized risk factor for weight gain, but repeatability of TEE, a critical variable in longitudinal studies of energy balance, is understudied. We examine repeated doubly labeled water (DLW) measurements of TEE in 348 adults and 47 children from the IAEA DLW Database (mean ± SD time interval: 1.9 ± 2.9 y) to assess repeatability of TEE, and to examine if TEE adjusted for age, sex, fat-free mass, and fat mass is associated with changes in weight or body composition. Here, we report that repeatability of TEE is high for adults, but not children. Bivariate Bayesian mixed models show no among or within-individual correlation between body composition (fat mass or percentage) and unadjusted TEE in adults. For adults aged 20–60 y (N = 267; time interval: 7.4 ± 12.2 weeks), increases in adjusted TEE are associated with weight gain but not with changes in body composition; results are similar for subjects with intervals >4 weeks (N = 53; 29.1 ± 12.8 weeks). This suggests low TEE is not a risk factor for, and high TEE is not protective against, weight or body fat gain over the time intervals tested. 

Total daily energy expenditure (“total expenditure”) reflects daily energy needs and is a critical variable in human health and physiology, but its trajectory over the life course is poorly studied. We analyzed a large, diverse database of total expenditure measured by the doubly labeled water method for males and females aged 8 days to 95 years. Total expenditure increased with fat-free mass in a power-law manner, with four distinct life stages. Fat-free mass–adjusted expenditure accelerates rapidly in neonates to ~50% above adult values at ~1 year; declines slowly to adult levels by ~20 years; remains stable in adulthood (20 to 60 years), even during pregnancy; then declines in older adults. These changes shed light on human development and aging and should help shape nutrition and health strategies across the life span.