Conflict management in rooks (Corvus frugilegus): Victims do not display post-conflict affiliation but avoid their former aggressor.

Many social species use post-conflict behaviors to mitigate the consequences of conflicts. One of these behaviors is the victim's affiliation with its former opponent following conflict in an attempt to restore the damaged relationship. The victim can also affiliate with a third party. Affiliation with former opponents and third parties also alleviates stress. Studies of conflict management strategies in birds mostly concern corvids, and more specifically rooks (Corvus frugilegus). In this colonial pair-bonded species, the most valuable relationship is with the mate. It is rarely conflictual, meaning that there is generally no need for any post-conflict affiliation. However, conflicts occur with other social partners, and victims may primarily use third-party affiliation to avoid renewed aggression after conflicts. Previous studies of rooks failed to show a protective role of third-party affiliations for rook victims. The present study seeks to further investigate the use and efficiency of these conflict management strategies from the victim's perspective. We recorded conflicts and post-conflict behaviors in captive rooks using the standard post-conflict matched control comparison method. Victims did not affiliate with their former opponent or with third parties after conflict, but rather avoided their former aggressor, thus successfully limiting the risk of renewed aggression. Post-conflict affiliations are not observed in all rook colonies, suggesting that avoidance of the former aggressor may be a more commonly used strategy than previously thought.

Lateralization of Eye Use in Cuttlefish: Opposite Direction for Anti-Predatory and Predatory Behaviors.

Vertebrates with laterally placed eyes typically exhibit preferential eye use for ecological activities such as scanning for predators or prey. Processing visual information predominately through the left or right visual field has been associated with specialized function of the left and right brain. Lateralized vertebrates often share a general pattern of lateralized brain function at the population level, whereby the left hemisphere controls routine behaviors and the right hemisphere controls emergency responses. Recent studies have shown evidence of preferential eye use in some invertebrates, but whether the visual fields are predominately associated with specific ecological activities remains untested. We used the European common cuttlefish, Sepia officinalis, to investigate whether the visual field they use is the same, or different, during anti-predatory, and predatory behavior. To test for lateralization of anti-predatory behavior, individual cuttlefish were placed in a new environment with opaque walls, thereby obliging them to choose which eye to orient away from the opaque wall to scan for potential predators (i.e., vigilant scanning). To test for lateralization of predatory behavior, individual cuttlefish were placed in the apex of an isosceles triangular arena and presented with two shrimp in opposite vertexes, thus requiring the cuttlefish to choose between attacking a prey item to the left or to the right of them. Cuttlefish were significantly more likely to favor the left visual field to scan for potential predators and the right visual field for prey attack. Moreover, individual cuttlefish that were leftward directed for vigilant scanning were predominately rightward directed for prey attack. Lateralized individuals also showed faster decision-making when presented with prey simultaneously. Cuttlefish appear to have opposite directions of lateralization for anti-predatory and predatory behavior, suggesting that there is functional specialization of each optic lobe (i.e., brain structures implicated in visual processing). These results are discussed in relation to the role of lateralized brain function and the evolution of population level lateralization.