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For group-living animals traveling through heterogeneous landscapes, collective movement can be influenced by both habitat structure and social interactions. Yet research in collective behavior has largely neglected habitat influences on movement. Here we integrate simultaneous, high-resolution, tracking of wild baboons within a troop with a 3-dimensional reconstruction of their habitat to identify key drivers of baboon movement. A previously unexplored social influence - baboons' preference for locations that other troop members have recently traversed - is the most important predictor of individual movement decisions. Habitat is shown to influence movement over multiple spatial scales, from long-range attraction and repulsion from the troop's sleeping site, to relatively local influences including road-following and a short-range avoidance of dense vegetation. Scaling to the collective level reveals a clear association between habitat features and the emergent structure of the group, highlighting the importance of habitat heterogeneity in shaping group coordination.

When members of a group differ in locomotor capacity, coordinating collective movement poses a challenge: some individuals may have to move faster (or slower) than their preferred speed to remain together. Such compromises have energetic repercussions, yet research in collective behaviour has largely neglected locomotor consensus costs. Here, we integrate high-resolution tracking of wild baboon locomotion and movement with simulations to demonstrate that size-based variation in locomotor capacity poses an obstacle to the collective movement. While all baboons modulate their gait and move-pause dynamics during collective movement, the costs of maintaining cohesion are disproportionately borne by smaller group members. Although consensus costs are not distributed equally, all group-mates do make locomotor compromises, suggesting a shared decision-making process drives the pace of collective movement in this highly despotic species. These results highlight the importance of considering how social dynamics and locomotor capacity interact to shape the movement ecology of group-living species. [ABSTRACT FROM AUTHOR]

Biochemical reference intervals are important for assessing the health of target species and populations by identifying abnormalities in key blood parameters. Although reference intervals have been established for baboons in captivity, the lack of data from free-ranging individuals makes it difficult to interpret the results of their blood chemistry panels or to assess and monitor the health of wild baboon populations. The goal of this study was therefore to establish serum biochemical reference intervals for free-ranging olive baboons (Papio anubis) in Kenya. We evaluated 14 biochemical parameters from 28 baboons sampled at the Mpala Research Center, Nanyuki, Kenya. Reference intervals obtained from this wild population were comparable to those from captive baboon populations. Alkaline phosphatase (ALP) and phosphorus levels differed significantly among age classes; both were higher in subadult and juvenile baboons than in adults. However, none of the components of the blood biochemistry panel differed significantly between the sexes. The reference intervals we report provide a baseline for the evaluation and treatment of free-ranging olive baboons and provide context for interpreting the biochemical profiles of captive individuals. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "Locomotor compromises maintain group cohesion in baboon troops on the move" which appeared in the 28 July 2021 issue.

Sleep is fundamental to the health and fitness of all animals. The physiological importance of sleep is underscored by the central role of homeostasis in determining sleep investment -- following periods of sleep deprivation, individuals experience longer and more intense sleep bouts. Yet, most sleep research has been conducted in highly controlled settings, removed from evolutionarily relevant contexts that may hinder the maintenance of sleep homeostasis. Using triaxial accelerometry and GPS to track the sleep patterns of a group of wild baboons (Papio anubis), we found that ecological and social pressures indeed interfere with homeostatic sleep regulation. Baboons sacrificed time spent sleeping when in less familiar locations and when sleeping in proximity to more group- mates, regardless of how long they had slept the prior night or how much they had physically exerted themselves the preceding day. Further, they did not appear to compensate for lost sleep via more intense sleep bouts. We found that the collective dynamics characteristic of social animal groups persist into the sleep period, as baboons exhibited synchronized patterns of waking throughout the night, particularly with nearby group- mates. Thus, for animals whose fitness depends critically on avoiding predation and developing social relationships, maintaining sleep homeostasis may be only secondary to remaining vigilant when sleeping in risky habitats and interacting with group-mates during the night. Our results highlight the importance of studying sleep in ecologically relevant contexts, where the adaptive function of sleep patterns directly reflects the complex tradeoffs that have guided its evolution. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Shared decision-making drives collective movement in wild baboons" by Ariana Strandburg-Peshkin and colleagues in the June 19, 2015, issue, along with a reply from the authors.