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Reintroduction of separated individuals into their social group is a major problem in the management of captive group of non-human primates. Here we report a case in captive Tonkean macaques in which a female infant was abandoned by her mother after birth, then removed, hand-reared, and reintroduced after weaning to her original group in several stages. After the initial phase of separation, a period of habituation to group members followed during which the infant was brought to the front of the group enclosure daily for two months. We then started a phased reintroduction process that lasted a year. Because the biological mother was the group member most attracted to the infant, the process began by allowing the two individuals to interact. In the next stages, we introduced the infant to the other individuals one after the other, starting with the females. Females then acted as protectors against potential male aggression. At the age of one year and two months, the introduced individual had fully integrated her original group. Two years later, she appeared to behave like the other group members. This report shows that a phased process can be used to reintroduce an infant to a macaque group containing several adult females and males.

Despite the domestication of sheep and goats by humans for several millennia, we still lack comparative data on their cognitive capacity. Comparing the cognitive skills of farm animals can help understand the evolution of cognition. In this study, we compared the performances of sheep and goats in inference by exclusion tasks. We implemented two tasks, namely a cup task and a tube task, to identify whether success in solving the task could be attributed to either low-level mechanisms (avoiding the empty location strategy) or to deductive reasoning (if two possibilities A and B, but not A, then it must be B). In contrast to a previous study comparing goats and sheep in a cup task, we showed that both species solved the inferential condition with high success rates. In the tube task, performances could not be explained by alternative strategies such as avoiding the empty tube or preferring the bent tube. When applying a strict set of criteria concerning responses in all conditions and controlling for the potential effects of experience, we demonstrate that two individuals, a goat and a sheep, fulfil these criteria. This suggests that sheep and goats are able to make inferences based on deductive reasoning.

Recruitment is a process by which animals can initiate collective movements: the action of an individual prompts conspecifics to follow. Although it has been hypothesized that animals may be able to intentionally recruit others, there is no experimental evidence of this to date. We tested this hypothesis in two pairs of Tonkean macaques in a situation requiring the subjects to find a food site in a 2800 m

International audience; It was long assumed that only humans can distinguish the living from the dead. Renewed interest in this question over the last decade has led several authors to assert that non-human primates are also aware of death. We investigate this issue by comparing the behaviours of monkeys and great apes toward helpless conspecifics, basing our analysis on published reports. We first examine the behaviours of mothers towards the body of their dead offspring. They may carry the corpse for days or more before abandoning it. They groom, inspect and protect it, sometimes allowing group members to explore it, and rare cases of cannibalism have been reported. No significant difference is observed in the way that monkeys and great apes treat the bodies of infants. We then examine responses to collapsed (still able to move and react) and inanimate (unresponsive or dead) conspecifics. Monkeys and great apes guard, care for and inspect their helpless partners, and also manipulate and mobilise them. Through these actions, individuals may inform themselves about the state of their partners, test their responsiveness and/or attempt to rouse them. It appears that only chimpanzees and gorillas show violent action such as display behaviours and the rough treatment of bodies. They can also make distress calls, and periods of "stunned silence" sometimes occur in chimpanzees, indicating that they are experiencing intense emotion. Finally, we argue that while both monkeys and great apes detect body dysfunction through the victims' inability to wake up and move, only great apes can understand that something serious has happened. The signs of emotional disturbance reported in them indicate that they may believe that inanimate conspecifics have entered a state of "dormancy", meaning that they are unlikely to regain wakefulness. However, there is no evidence that any non-human primates are aware of mortality.

Large-scale studies of individual differences in animal innovation are rare firstly because discovery behaviour itself is often rare, and secondly because of logistical difficulties associated with obtaining observational data on a large number of innovative individuals across multiple groups and locations. Here we take a different approach, using observer ratings to study innovative behaviour in 127 brown capuchin monkeys (Sapajus [Cebus] sp.) from 15 social groups and 7 facilities. Capuchins were reliably rated by 1 to 7 raters (mean 3.2 ± 1.6 raters/monkey) on a 7-point Likert scale for levels of innovative behaviour, task motivation, sociality, and dominance. In a subsample, we demonstrate these ratings are valid: rated innovation predicted performance on a learning task, rated motivation predicted participation in the task, rated dominance predicted social rank based on win/loss aggressive outcomes, and rated sociality predicted the time that monkeys spent in close proximity to others. Across all 127 capuchins, individuals that were rated as being more innovated were significantly younger, more social, and more motivated to engage in tasks. Sociality, task motivation, and age all had independent effects on innovativeness, whereas sex, dominance and group size were non-significant. Our findings are consistent with long-term behavioural observations of innovation in wild white-faced capuchins. Observer ratings may therefore be a valid tool for studies of animal innovation, and our findings highlight in particular several possible scenarios through which innovative behaviour might be selected for among capuchins.

International audience

International audience; The study of the metabolome within tissues, organisms, cells or biofluids can be carried out by several bioanalytical techniques. Among them, nuclear magnetic resonance (NMR) is one of the principal spectroscopic methods. This is due to a sample rotation technique, high-resolution magic angle spinning (HR-MAS), which targets the analysis of heterogeneous specimens with a bulk sample mass from 5 to 10 mg. Recently, a new approach, high-resolution micro-magic angle spinning (HR-$\mu$MAS), has been introduced. It opens, for the first time, the possibility of investigating microscopic specimens (

The study of the metabolome within tissues, organisms, cells or biofluids can be carried out by several bioanalytical techniques. Among them, nuclear magnetic resonance (NMR) is one of the principal spectroscopic methods. This is due to a sample rotation technique, high-resolution magic angle spinning (HR-MAS), which targets the analysis of heterogeneous specimens with a bulk sample mass from 5 to 10 mg. Recently, a new approach, high-resolution micro-magic angle spinning (HR-μMAS), has been introduced. It opens, for the first time, the possibility of investigating microscopic specimens (

This work was supported by grants from the Agence Nationale de la Recherche (ANR-08-412 BLAN-0042-01) and the European Science Foundation (Compcog Exchange Grant N°3648). Many studies investigate the decisions made by animals by focussing on their individual attitudes towards risk, i.e., risk seeking, risk neutrality or risk aversion. However, little attention has been paid to how far individuals understand the different odds of outcomes. In a previous gambling task involving up to 18 different lotteries (Pelé et al., 2014), non-human primates used probabilities of gains and losses to make their decision. Although the use of complex mathematical calculation for decision-making seemed unlikely, we applied a gradual decrease in the chances to win throughout the experiment. This probably facilitated the extraction of information about odds. Here, we investigated whether individuals would still make efficient decisions if this facilitating factor was removed. To do so, we randomized the order of presentation of the 18 lotteries. Individuals from four ape and two monkey species were tested. Only capuchin monkeys differed in their gambling behaviour, playing even when there was nothing to win. Randomising the lottery presentation order leads all species to predominantly use a maximax heuristic in which individuals gamble as soon as there is at least one chance to win more than they already possess, whatever the risk. Most species also gambled more as the frequency of larger rewards increased. These results suggest the occurrence of optimistic behaviour. The maximax heuristic is sometimes observed in human managerial and financial decision-making, where risk is ignored for potential gains, however low they may be. Our results suggest a shared and strong propensity in primates to rely on heuristics whenever complexity in evaluation of outcome odds arises. Postprint Postprint