Biology subjects

Boogert, N. J.

Publications and source records attributed to Boogert, N. J..

3 recordsLinked to original sources

bioRxiv2018

The role of tactile interactions in flight responses in the Bronze Cory catfish (Corydoras aeneus)

One of the primary functions of animal aggregations is defense against predators. Many social animals enjoy reduced predation risk as a result of grouping, and individuals within groups can benefit from information transferred by their group-mates about a potential predator. We present evidence that a tactile interaction behavior we term nudging substantially modified group responses to a potential threat in a highly social catfish species, Corydoras aeneus. These catfish deployed nudges during flight responses, and these nudges were associated with a greater likelihood of group cohesion following a threat event. Increased nudging behavior resulted in longer flight responses. In addition, individuals that perceived the threat first were more likely to initiate nudges, implying that nudges could be used to alert group-mates to the presence of a threat. Taken together, our results suggest that tactile communication plays an important role in gaining anti-predator benefits from sociality in these fish.

animal behavior and cognition↗

bioRxiv2018

Coping with strangers: how familiarity and active interactions shape group coordination in Corydoras aeneus

Social groups whose members have had sustained prior experience with each other frequently exhibit improved coordination and outperform groups whose members are unfamiliar with one another. The mechanisms by which familiarity assists coordination are not well known. Prior social experience may simply allow individuals to learn the behavioral tendencies of familiar group-mates and coordinate accordingly. In the absence of prior social experience, it would be adaptive for individuals to develop strategies for coping with unfamiliar others to minimize the disadvantage of unfamiliarity. To explore the dynamics of familiarity in shaping group behaviors, we used a highly social catfish, Corydoras aeneus, that utilizes a distinctive, observable tactile interactions. Here we describe this tactile interaction behavior, physical \"nudges\" that are deployed to initiate group movements and maintain contact with group-mates during group movements. We then report the results of two experiments exploring the relationship between nudges and coordination. First, within triplets of two familiar and one unfamiliar individual, we found no individual differences in nudging rate based on familiarity. Despite all individuals interacting at similar rates, however, unfamiliar individuals failed to coordinate as well as their familiar group-mates, and were more frequently absent from group movements. Second, comparing pairs of familiar with pairs of unfamiliar fish, there was no difference in the level of coordination between pairs. Instead, we found that unfamiliar pairs exhibited significantly higher nudging rates, suggesting that unfamiliar pairs could compensate for their unfamiliarity by nudging more frequently. In contrast, familiar individuals coordinated with comparatively little nudging, presumably because they were experienced with each other. Overall, these results suggest that nudges can be used to improve coordination of group activities, but that their usage is reduced in the case of familiar individuals, implying that these potential signals may be costly.

animal behavior and cognition↗

bioRxiv2017

Consistent Individual Differences Drive Collective Behaviour And Group Functioning Of Schooling Fish

The ubiquity of consistent inter-individual differences in behaviour ( animal personalities) 1,2, suggests they may constitute a fundamental component of animal groups that may drive their functioning 3,4. Despite increasing evidence that highlights their importance 5-16, we still lack a unified mechanistic frame-work to explain and predict how inter-individual differences may affect collective behaviour. Here we investigate how differences in individual behavioural tendencies affect the group structure, movement dynamics, and foraging behaviour of animal groups using free-swimming stickleback fish (Gasterosteus aculeatus). Analysis of high-resolution tracking data of known individuals demonstrates that, across a range of contexts, consistent inter-individual differences in social proximity were strongly linked to speed and, together with boldness predicted spatial positioning and leadership within groups, differences in structure and movement dynamics between groups, as well as individual and group foraging performance. These effects of inter-individual behavioural variation on group-level states emerged naturally from a generic model of heterogeneous, self-organising groups. Our study combines experimental and theoretical evidence for a simple mechanism to explain variation in the emergence of structure, dynamics, and functional capabilities of groups across social and ecological scales. In addition, we show that individual performance was conditional to the group composition, providing a potential basis for social selection driving behavioural differentiation between individuals.

animal behavior and cognition↗