Biology subjects

Delacoux, M.

Publications and source records attributed to Delacoux, M..

3 recordsLinked to original sources

bioRxiv2025

Rapid Social Transmission of Predator Location via Gaze Following in Pigeons

Social information transmission is a key advantage of group living, particularly in uncertain or high-stakes contexts. During collective predator vigilance, individuals often initiate evasive action based on social cues--such as the escape behaviour of others--before detecting threats themselves. Yet these cues can be ambiguous or misleading, leading to costly false alarms. Gaze following, a key socio-cognitive skill widespread across species, may reduce this ambiguity by allowing individuals to localize threats with minimal effort and avoid unnecessary escapes. Although this vigilance function has long been hypothesized, direct evidence is lacking. Here we show that pigeons foraging in flocks detect a predator and socially transmit its location rapidly via gaze following, before any escape behaviour occurs. In experiments simulating predator attacks, we reconstructed predator-oriented gaze using high-resolution posture tracking and modelled social transmission with dynamic multi-network Bayesian models. Comparing models based on distinct social cues, we found that pigeons responded selectively to conspecific gaze toward the predator, rather than locomotion, head-up vigilance, or gaze elsewhere. Analyses of network structure further revealed that this transmission occurs through visually connected networks, particularly via peripheral rather than foveal vision. While individuals occasionally followed gaze to non-threatening locations, flocks reliably converged on the actual threat. These findings uncover a previously undocumented, cognition-based mechanism of collective detection. To our knowledge, this is the first evidence that gaze following serves an adaptive function in survival contexts, illustrating how individual-level cognition and group-level dynamics interact to the adaptive value of group living.

animal behavior and cognition↗

bioRxiv2024

Gaze Following in Pigeons Increases with the Number of Demonstrators

Gaze following, orienting ones gaze in the same direction as another individual, is widespread across species and well-studied in terms of cognitive mechanisms. However, the role of collective context on this behavior is less understood. This study tested whether the number of conspecifics looking in a particular direction facilitates gaze following in pigeons (Columba livia). We presented attention-getting stimuli to subsets of pigeons (demonstrators), while other pigeons (observers) could not see the stimuli directly. We used a motion-capture system to track fine-scale movements of head and body orientations. Observer pigeons followed the gaze of demonstrators, specifically toward the target object rather than a perceptually similar distractor. Critically, the likelihood and frequency of gaze following increased with the number of demonstrators looking at the target. We observed no nonlinear effects, such as saturation or quorum thresholds, in this increasing trend, at least under our experimental conditions. In group-living species like pigeons, multiple individuals looking in the same direction may serve as a more reliable social signal. To our knowledge, this is the first study to demonstrate that the number of demonstrators influences gaze following in non- human animals, highlighting the critical role of collective context in animal social cognition.

animal behavior and cognition↗

bioRxiv2024

Fine-scale tracking reveals visual field use for predator detection and escape in collective foraging of pigeon flocks

During collective vigilance, it is commonly assumed that individual animals compromise their feeding time to be vigilant against predators, benefiting the entire group. One notable issue with this assumption concerns the unclear nature of predator "detection", particularly in terms of vision. It remains uncertain how a vigilant individual utilizes its high-acuity vision (such as the fovea) to detect a predator cue and subsequently guide individual and collective escape responses. Using fine-scale motion capture technologies, we tracked the head and body orientations of pigeons (hence reconstructed their visual fields and foveal projections) foraging in a flock during simulated predator attacks. Pigeons used their fovea to inspect predator cues. Earlier foveation on a predator cue was linked to preceding behaviors related to vigilance and feeding, such as head-up or down positions, head-scanning, and food-pecking. Moreover, earlier foveation predicted earlier evasion flights at both the individual and collective levels. However, we also found that relatively long delay between their foveation and escape responses in individuals obscured the relationship between these two responses. While our results largely support the existing assumptions about vigilance, they also underscore the importance of considering vision and addressing the disparity between detection and escape responses in future research.

animal behavior and cognition↗