Domestic gardens as favorable pollinator habitats in impervious landscapes.

Urban expansion is correlated to negative biodiversity trends. The amount of impervious surfaces in urban areas is a determinant of pollinator species assemblages. While the increase in urbanization and impervious surfaces negatively impacts pollinators, cities also encompass urban green spaces, which have a significant capacity to support biodiversity. Among them, domestic gardens that represent a non-negligible fraction of green spaces have been shown to benefit pollinators. Domestic gardens may form habitat clusters in residential areas, although their value at a landscape scale is still unknown. Here, we investigate the combined effects of impervious surfaces and domestic garden areas on pollinator richness. Due to the difficulty of accessing privately owned domestic gardens, we chose to use citizen science data from a well-established French citizen science program known as SPIPOLL. Using regression tree analysis on buffers located from 50 m to 1000 m around the data points, we show the importance of pollinators being in close proximity to domestic gardens as locally favorable habitats that are embedded within a landscape, in which impervious surfaces represent unfavorable areas. We highlight the inter-connection between local and landscape scales, the potential for patches of domestic gardens in residential areas, and the need to consider the potential of gardeners' coordinated management decisions within a landscape context.

Social grooming network in captive chimpanzees: does the wild or captive origin of group members affect sociality?

Many chimpanzees throughout the world are housed in captivity, and there is an increasing effort to recreate social groups by mixing individuals with captive origins with those with wild origins. Captive origins may entail restricted rearing conditions during early infant life, including, for example, no maternal rearing and a limited social life. Early rearing conditions have been linked with differences in tool-use behavior between captive- and wild-born chimpanzees. If physical cognition can be impaired by non-natural rearing, what might be the consequences for social capacities? This study describes the results of network analysis based on grooming interactions in chimpanzees with wild and captive origins living in the Kumamoto Sanctuary in Kumamoto, Japan. Grooming is a complex social activity occupying up to 25% of chimpanzees' waking hours and plays a role in the emergence and maintenance of social relationships. We assessed whether the social centralities and roles of chimpanzees might be affected by their origin (captive vs wild). We found that captive- and wild-origin chimpanzees did not differ in their grooming behavior, but that theoretical removal of individuals from the network had differing impacts depending on the origin of the individual. Contrary to findings that non-natural early rearing has long-term effects on physical cognition, living in social groups seems to compensate for the negative effects of non-natural early rearing. Social network analysis (SNA) and, in particular, theoretical removal analysis, were able to highlight differences between individuals that would have been impossible to show using classical methods. The social environment of captive animals is important to their well-being, and we are only beginning to understand how SNA might help to enhance animal welfare.

Evidence that monkeys (Macaca tonkeana and Sapajus apella) read moves, but no evidence that they read goals.

Whereas most experiments indicate that monkeys have no theory of mind, a study carried out by Wood and collaborators (2007) claimed that they can make inferences about the intentions of another individual. We applied the experimental procedure devised by these authors to investigate whether monkeys can recognize goal-directed actions. We tested 16 Tonkean macaques (Macaca tonkeana) and 12 tufted capuchin monkeys (Sapajus apella). Each subject was submitted to 24 trials in randomized order. The experimenter presented 2 containers, 1 of which was potentially baited with a food reward. After the experimenter had either intentionally or accidentally made an action on 1 of the containers, the subject was asked to select 1 of them. We found that individuals in both species failed to distinguish between accidental and intentional actions. However, they displayed a significant preference for the container touched by the experimenter in the hand conditions, and not in the elbow conditions. These results do not support those reported by Wood and collaborators, but they are consistent with other studies concluding that monkeys are not capable of mind reading.

Lack of evidence that Tonkean macaques understand what others can hear.

By distinguishing the attentional cues of their mates, animals can learn what part of their environment is of potential interest. However, recognizing the attentional states of others through auditory perception appears to be difficult, since these states are generally not accompanied by ostensive signals liable to reveal them. In this context, one study found that rhesus macaques withhold their action when unobserved, then concluding that they know what others can hear. We replicated this study by testing 18 Tonkean macaques in an experimental setting where subjects had to choose between two boxes containing a food reward. One box made a noise when opened, and the other opened silently. An experimenter was present and could either have her back to subjects or be facing them. If subjects aimed to avoid attracting the experimenter's attention, they were expected to select the silent box while the experimenter's back was turned. Results showed that subjects did not discriminate between boxes, whatever the experimenter's position. We thus found no evidence that Tonkean macaques are able to take the auditory attentional states of a human into account. It is therefore premature to conclude that monkeys can establish a link between hearing and knowing.

Social networks in primates: smart and tolerant species have more efficient networks.

Network optimality has been described in genes, proteins and human communicative networks. In the latter, optimality leads to the efficient transmission of information with a minimum number of connections. Whilst studies show that differences in centrality exist in animal networks with central individuals having higher fitness, network efficiency has never been studied in animal groups. Here we studied 78 groups of primates (24 species). We found that group size and neocortex ratio were correlated with network efficiency. Centralisation (whether several individuals are central in the group) and modularity (how a group is clustered) had opposing effects on network efficiency, showing that tolerant species have more efficient networks. Such network properties affecting individual fitness could be shaped by natural selection. Our results are in accordance with the social brain and cultural intelligence hypotheses, which suggest that the importance of network efficiency and information flow through social learning relates to cognitive abilities.