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Activity range – the amount of time spent active per day – is a fundamental aspect contributing to the optimization process by which animals achieve energetic balance. Based on their size and the nature of their diet, theoretical expectations are that larger carnivores need more time active to fulfil their energetic needs than do smaller ones and also more time active than similar‐sized non‐carnivores. Despite the relationship between daily activity, individual range and energy acquisition, large‐scale relationships between activity range and body mass among wild mammals have never been properly addressed. This study aimed to understand the scaling of activity range with body mass, while controlling for phylogeny and diet. We built simple empirical predictions for the scaling of activity range with body mass for mammals of different trophic guilds and used a phylogenetically controlled mixed model to test these predictions using activity records of 249 mammal populations (128 species) in 19 tropical forests (in 15 countries) obtained using camera traps. Our scaling model predicted a steeper scaling of activity range in carnivores (0.21) with higher levels of activity (higher intercept), and near‐zero scaling in herbivores (0.04). Empirical data showed that activity ranges scaled positively with body mass for carnivores (0.061), which also had higher intercept value, but not for herbivores, omnivores and insectivores, in general, corresponding with the predictions. Despite the many factors that shape animal activity at local scales, we found a general pattern showing that large carnivores need more time active in a day to meet their energetic demands.

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In this paper we present observations of individuals of the bee species Trigona recursa feeding on the fruits of Crotalaria micans. This plant, which contains pyrrolizidine alkaloids, is known to be toxic to humans, mammals and poultry. Over the course of three days, we observed a large number of bees feeding on many individual Crotalaria micans plants in an urban fragment of Brazilian Savanna. The bees preferred greener fruits, which are the softest and most toxic. Consumption of the plant had no immediately apparent fatal effect on the bees, since we did not find any dead individuals near the observation site. Some insect species are known to use pyrrolizidine and alkaloids for defense by incorporating them into their body or using them as precursors to pheromones. Trigona recursa and other bee species have not been previously recorded consuming Crotalaria micans and it is unclear what their motivation may be. We present these observations as a novel finding of the feeding behavior of Trigona recursa.