How animals that live in groups reach consensus regarding the actions of the collective is a fundamental question in the study of behaviour. We address this issue using homing pigeons as a model system. Much of what we know about avian navigation comes from studies of the homing pigeon, and while emphasis has traditionally been on the mechanisms that individual birds use to orient, under natural conditions these birds tend to travel together in groups. Such groups will typically be composed of individuals differing in various attributes (age, sex, experience, knowledge, motivational state), raising interesting questions about the mechanisms that allow members to resolve any potential differences in individual navigational preferences.
Our experiments thus focus on how birds reach a consensus during group movement. Making use of our previous discovery that given sufficient experience with an area individual pigeons come to develop highly stereotyped, idiosyncratic homing routes, we can create flocks of various sizes that contain varying levels of disagreement among birds regarding the "correct" way home. How do birds with different preferred routes negotiate a joint path? How does the degree of disagreement between birds affect the outcome of the decision-making process? How do individual attributes contribute to birds' tendencies to act as leaders or followers and what effect does this have on the accuracy and speed of decisions? Can group members gauge who is best informed?
Our experimental work is combined with theoretical approaches aimed at modelling the mechanisms of group decision making at work during collective movement. By understanding the rules that birds follow when they respond to or interact with fellow group members, we hope to gain an insight into how collectives are shaped by the individuals of which they are composed. Problems of group coordination are shared by many different social-living species and in a variety of different scenarios - the rules uncovered in our work are likely to have implications in a diverse range of contexts.
Please visit the PigeonHierarchies website for more information on our 2013 paper in PNAS and the PigeonFlocks website for more information on our 2010 paper in Nature.
