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Black‐and‐white snub‐nosed monkeys (Rhinopithecus bieti) rely on behavioral and dietary flexibility to survive in temperate latitudes at high‐elevation habitats characterized by climate and resource seasonality. However, little is known about how elevation influences their behavioral and dietary flexibility at monthly or seasonal scales. We studied an isolated R. bieti population at Mt. Lasha in the Yunling Provincial Nature Reserve, Yunnan, China, between May 2008 and August 2016 to assess the impacts of elevation on feeding behavior and diet. Across our sample, R. bieti occupied elevations between 3031 and 3637 m above mean sea level (amsl), with a 315.1 m amsl range across months and a 247.3 m amsl range across seasons. Contrary to expectations, individuals spent less time feeding when ranging across higher elevations. Lichen consumption correlated with elevation use across months and seasons, with individuals spending more time feeding on this important resource at higher elevations. Leaf consumption only correlated with elevation use during the spring. Our results suggest that R. bieti do not maximize their food intake at higher elevations and that monthly and seasonal changes in lichen and leaf consumption largely explain variation in elevation use. These findings shed light on the responses of R. bieti to environmental change and offer insight into strategies for conserving their habitats in the face of anthropogenic disturbance. Research Highlights: Black‐and‐white snub‐nosed monkeys (Rhinopithecus bieti) spend less time feeding in months and seasons when occupying higher‐elevation habitats.Leaves only comprise a higher percentage of the R. bieti diet when occupying higher‐elevation habitats in the spring.Lichen comprise a higher percentage of the R. bieti diet in months and seasons when occupying higher‐elevation habitats. [ABSTRACT FROM AUTHOR]

Objectives The birth process has been studied extensively in many human societies, yet little is known about this essential life history event in other primates. Here, we provide the most detailed account of behaviors surrounding birth for any wild nonhuman primate to date. Materials and Methods Over a recent ∼10-year period, we directly observed 15 diurnal births (13 live births and 2 stillbirths) among geladas ( Theropithecus gelada) at Guassa, Ethiopia. During each birth, we recorded the occurrence (or absence) of 16 periparturitional events, chosen for their potential to provide comparative evolutionary insights into the factors that shaped birth behaviors in humans and other primates. Results We found that several events (e.g., adopting standing crouched positions, delivering infants headfirst) occurred during all births, while other events (e.g., aiding the infant from the birth canal, licking infants following delivery, placentophagy) occurred during, or immediately after, most births. Moreover, multiparas ( n = 9) were more likely than primiparas ( n = 6) to (a) give birth later in the day, (b) isolate themselves from nearby conspecifics while giving birth, (c) aid the infant from the birth canal, and (d) consume the placenta. Discussion Our results suggest that prior maternal experience may contribute to greater competence or efficiency during the birth process. Moreover, face presentations (in which infants are born with their neck extended and their face appearing first, facing the mother) appear to be the norm for geladas. Lastly, malpresentations (in which infants are born in the occiput anterior position more typical of human infants) may be associated with increased mortality in this species. We compare the birth process in geladas to those in other primates (including humans) and discuss several key implications of our study for advancing understanding of obstetrics and the mechanism of labor in humans and nonhuman primates. [ABSTRACT FROM AUTHOR]