Dataset Information

Role of projection in the control of bird flocks.

ABSTRACT: Swarming is a conspicuous behavioral trait observed in bird flocks, fish shoals, insect swarms, and mammal herds. It is thought to improve collective awareness and offer protection from predators. Many current models involve the hypothesis that information coordinating motion is exchanged among neighbors. We argue that such local interactions alone are insufficient to explain the organization of large flocks of birds and that the mechanism for the exchange of long-range information necessary to control their density remains unknown. We show that large flocks self-organize to the maximum density at which a typical individual still can see out of the flock in many directions. Such flocks are marginally opaque--an external observer also still can see a substantial fraction of sky through the flock. Although this seems intuitive, we show it need not be the case; flocks might easily be highly diffuse or entirely opaque. The emergence of marginal opacity strongly constrains how individuals interact with one another within large swarms. It also provides a mechanism for global interactions: an individual can respond to the projection of the flock that it sees. This provides for faster information transfer and hence rapid flock dynamics, another advantage over local models. From a behavioral perspective, it optimizes the information available to each bird while maintaining the protection of a dense, coherent flock.

SUBMITTER: Pearce DJ

PROVIDER: S-EPMC4115545 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Publications

Role of projection in the control of bird flocks.

Pearce Daniel J G DJ Miller Adam M AM Rowlands George G Turner Matthew S MS

Proceedings of the National Academy of Sciences of the United States of America 20140707 29

Swarming is a conspicuous behavioral trait observed in bird flocks, fish shoals, insect swarms, and mammal herds. It is thought to improve collective awareness and offer protection from predators. Many current models involve the hypothesis that information coordinating motion is exchanged among neighbors. We argue that such local interactions alone are insufficient to explain the organization of large flocks of birds and that the mechanism for the exchange of long-range information necessary to ...[more]

PMID: 25002501

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Dataset Information

Role of projection in the control of bird flocks.

Publications

Role of projection in the control of bird flocks.

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