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Aspects of the feeding ecology of the threatened maned sloth (Bradypus torquatus Illiger, 1811) are poorly understood. Here, we evaluate the diet composition and the influence of leaf chemical compounds on the consumption of plant species by 10 radio-tracked individuals in southern Bahia and construct a list of plants consumed by the species based on our data and the available literature. We confirmed that the maned sloth is a strict folivore and consumes predominantly young leaves. We reported the consumption of 39 species, from 32 genera and 20 families of plants in southern Bahia, and provide an updated list of 68 species so far reported as consumed by maned sloths. The most frequently consumed species in southern Bahia belong to the genera Emmotum, Inga, Ficus and Brosimum, totalling almost half of the maned sloth's diet. Nevertheless, only Ficus spp. were widely consumed by maned sloths elsewhere. The low consumption of Cecropia spp. suggests that maned sloth's diet is not strongly linked to these taxa as reported for other Bradypus. None of the evaluated chemical compounds had a significant effect on the choice of plants consumed. Altogether, the available data indicated that the maned sloth is a generalist at the species level. In addition to morphological and physiological adaptations, it deals with the challenges of a foliage-based diet by selecting young leaves. Our update on maned sloth's diet may be used to overcome the difficulties of keeping and reproducing them in captivity and support actions that aim to recover their habitat.

Changes in ambient temperature and solar radiation may affect sloths' metabolic rate and body temperature, with consequent changes in activities, postures and microhabitat selection. Although the separate effect of temperature and solar radiation on sloth's behaviour have been previously studied, the combined effect of these climatic factors on behavioural aspects of sloths has never been systematically evaluated in field conditions. Here we evaluated the influence of hourly ambient temperature variation on maned sloth (Bradypus torquatus) activities, postures and tree crown positions, under sunny and cloudy conditions; and tested if any of the animal posture and position increase their exposure to human detection. We performed 350 h of visual observation on eight maned sloths, equipped with radio‐backpacks, in northern Bahia, Brazil, recording their activities, and their resting postures and positions on tree crowns. We also recorded the time taken to visualize the sloths on 58 days to analyse if sloths' detection is affected by posture and position. Higher ambient temperature, within a range of 21–33°C, increased the sloths' activity levels in cloudy conditions but reduced their activity in sunny conditions. Increasing ambient temperature also reduced the frequency of huddled posture and increased the frequency of extended posture and permanence in the inner tree crown. Lastly, the postures and positions did not influence sloths' detectability. Thus, the direction of the temperature–activity relationship depends on climatic conditions (sunny/cloudy), and individuals rely on resting postures and positions to thermoregulate. The warmer and drier future climate, expected to occur in the northern Atlantic Forest, may impose change in the diurnal activity levels and postural pattern for this threatened species, leading maned sloths to reduce its activity on sunny and warmer days and adopting an extended posture.

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