Male Wistar rats show individual differences in an animal model of conformity

Conformity refers to the act of changing one’s behaviour to match that of others. Recent studies in humans have shown that individual differences exist in conformity and that these differences are related to differences in neuronal activity. To understand the neuronal mechanisms in more detail, animal tests to assess conformity are needed. Here, we used a test of conformity in rats that has previously been evaluated in female, but not male, rats and assessed the nature of individual differences in conformity. Male Wistar rats were given the opportunity to learn that two diets differed in palatability. They were subsequently exposed to a demonstrator that had consumed the less palatable food. Thereafter, they were exposed to the same diets again. Just like female rats, male rats decreased their preference for the more palatable food after interaction with demonstrator rats that had eaten the less palatable food. Individual differences existed for this shift, which were only weakly related to an interaction between their own initial preference and the amount consumed by the demonstrator rat. The data show that this conformity test in rats is a promising tool to study the neurobiology of conformity

Social Transmission of Avoidance Behavior under Situational Change in Learned and Unlearned Rats

BACKGROUND: Rats receive information from other conspecifics by observation or other types of social interaction. Such social interaction may contribute to the effective adaptation to changes of environment such as situational switching. Learning to avoid dangerous places or objects rapidly occurs with even a single conditioning session, and the conditioned memory tends to be sustained over long periods. The avoidance is important for adaptation, but the details of the conditions under which the social transmission of avoidance is formed are unknown. We demonstrate that the previous experience of avoidance learning is important for the formation of behaviors for social transmission of avoidance and that the experienced rats adapt to a change of situation determined by the presence or absence of aversive stimuli. We systematically investigated social influence on avoidance behavior using a passive avoidance test in a light/dark two-compartment apparatus. METHODOLOGY/PRINCIPAL FINDINGS: Rats were divided into two groups, one receiving foot shocks and another with no aversive experience in a dark compartment. Experienced and inexperienced rats were further divided into subjects and partners. In Experiment 1, each subject experienced (1) interaction with an experienced partner, (2) interaction with an inexperienced partner, or (3) no interaction. In Experiment 2, each subject experienced interaction with a partner that received a shock. The entering latency to a light compartment was measured. The avoidance behavior of experienced rats was inhibited by interaction with inexperienced or experienced partners in a safely-changed situation. The avoidance of experienced rats was reinstated in a dangerously-changed situation by interaction with shocked rats. In contrast, the inexperienced rats were not affected by any social circumstances. CONCLUSIONS/SIGNIFICANCE: These results suggest that transmitted information among rats can be updated under a situational change and that the previous experience is crucial for social enhancement and inhibition of avoidance behavior in rats

The Maintenance of Traditions in Marmosets: Individual Habit, Not Social Conformity? A Field Experiment

Social conformity is a cornerstone of human culture because it accelerates and maintains the spread of behaviour within a group. Few empirical studies have investigated the role of social conformity in the maintenance of traditions despite an increasing body of literature on the formation of behavioural patterns in non-human animals. The current report presents a field experiment with free-ranging marmosets (Callithrix jacchus) which investigated whether social conformity is necessary for the maintenance of behavioural patterns within groups or whether individual effects such as habit formation would suffice.Using a two-action apparatus, we established alternative behavioural patterns in six family groups composed of 36 individuals. These groups experienced only one technique during a training phase and were thereafter tested with two techniques available. The monkeys reliably maintained the trained method over a period of three weeks, despite discovering the alternative technique. Three additional groups were given the same number of sessions, but those 21 individuals could freely choose the method to obtain a reward. In these control groups, an overall bias towards one of the two methods was observed, but animals with a different preference did not adjust towards the group norm. Thirteen of the fifteen animals that discovered both techniques remained with the action with which they were initially successful, independent of the group preference and the type of action (Binomial test: exp. proportion: 0.5, p<0.01).The results indicate that the maintenance of behavioural patterns within groups 1) could be explained by the first rewarded manipulation and subsequent habit formation and 2) do not require social conformity as a mechanism. After an initial spread of a behaviour throughout a group, this mechanism may lead to a superficial appearance of conformity without the involvement of such a socially and cognitively complex mechanism. This is the first time that such an experiment has been conducted with free-ranging primates

Local Individual Preferences for Nest Materials in a Passerine Bird

Variation in the behavioural repertoire of animals is acquired by learning in a range of animal species. In nest-building birds, the assemblage of nest materials in an appropriate structure is often typical of a bird genus or species. Yet plasticity in the selection of nest materials may be beneficial because the nature and abundance of nest materials vary across habitats. Such plasticity can be learned, either individually or socially. In Corsican populations of blue tits Cyanistes caeruleus, females regularly add in their nests fragments of several species of aromatic plants during the whole breeding period. The selected plants represent a small fraction of the species present in the environment and have positive effects on nestlings.We investigated spatiotemporal variations of this behaviour to test whether the aromatic plant species composition in nests depends on 1) plant availability in territories, 2) female experience or 3) female identity. Our results indicate that territory plays a very marginal role in the aromatic plant species composition of nests. Female experience is not related to a change in nest plant composition. Actually, this composition clearly depends on female identity, i.e. results from individual preferences which, furthermore, are repeatable both within and across years. A puzzling fact is the strong difference in plant species composition of nests across distinct study plots.This study demonstrates that plant species composition of nests results from individual preferences that are homogeneous within study plots. We propose several hypotheses to interpret this pattern of spatial variation before discussing them in the light of preliminary results. As a conclusion, we cannot exclude the possibility of social transmission of individual preferences for aromatic plants. This is an exciting perspective for further work in birds, where nest construction behaviour has classically been considered as a stereotypic behaviour

Resource distributions affect social learning on multiple timescales

We study how learning is shaped by foraging opportunities and self-organizing processes and how this impacts on the effects of “copying what neighbors eat” on multiple timescales. We use an individual-based model with a rich environment, where group foragers learn what to eat. We vary foraging opportunities by changing local variation in resources, studying copying in environments with pure patches, varied patches, and uniform distributed resources. We find that copying can help individuals explore the environment by sharing information, but this depends on how foraging opportunities shape the learning process. Copying has the greatest impact in varied patches, where local resource variation makes learning difficult, but local resource abundance makes copying easy. In contrast, copying is redundant or excessive in pure patches where learning is easy, and mostly ineffective in uniform environments where learning is difficult. Our results reveal that the mediation of copying behavior by individual experience is crucial for the impact of copying. Moreover, we find that the dynamics of social learning at short timescales shapes cultural phenomena. In fact, the integration of learning on short and long timescales generates cumulative cultural improvement in diet. Our results therefore provide insight into how and when such processes can arise. These insights need to be taken into account when considering behavioral patterns in nature

Observational Conditioning in Flower Choice Copying by Bumblebees (Bombus terrestris): Influence of Observer Distance and Demonstrator Movement

A. Avargues-Weber was funded by a postdoctoral fellowship from Fyssen fondation: http://www.fondationfyssen.fr/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

The acheulean handaxe : More like a bird's song than a beatles' tune?

© 2016 Wiley Periodicals, Inc. KV is supported by the Netherlands Organization for Scientific Research. MC is supported by the Canada Research Chairs Program, the Social Sciences and Humanities Research of Canada, the Canada Foundation for Innovation, the British Columbia Knowledge Development Fund, and Simon Fraser UniversityPeer reviewedPublisher PD

Collective animal navigation and migratory culture: From theoretical models to empirical evidence

Animals often travel in groups, and their navigational decisions can be influenced by social interactions. Both theory and empirical observations suggest that such collective navigation can result in individuals improving their ability to find their way and could be one of the key benefits of sociality for these species. Here, we provide an overview of the potential mechanisms underlying collective navigation, review the known, and supposed, empirical evidence for such behaviour and highlight interesting directions for future research. We further explore how both social and collective learning during group navigation could lead to the accumulation of knowledge at the population level, resulting in the emergence of migratory culture

Basic Taste Stimuli Elicit Unique Responses in Facial Skin Blood Flow

Facial expression changes characteristically with the emotions induced by basic tastes in humans. We tested the hypothesis that the five basic tastes also elicit unique responses in facial skin blood flow. Facial skin blood flow was measured using laser speckle flowgraphy in 16 healthy subjects before and during the application of basic taste stimuli in the oral cavity for 20 s. The skin blood flow in the eyelid increased in response to sweet and umami taste stimuli, while that in the nose decreased in response to a bitter stimulus. There was a significant correlation between the subjective hedonic scores accompanying these taste stimuli and the above changes in skin blood flow. These results demonstrate that sweet, umami, and bitter tastes induce unique changes in facial skin blood flow that reflect subjective hedonic scores