Pigeons have made contributions of considerable importance to humanity, especially during wars. In war, the homing ability of pigeons has been put to use by making them messengers. So-called war pigeons have carried many vital messages and some have been decorated for their services.

During World War I and II, carrier pigeons were used to transport messages back to their home coop behind the lines. When they landed, wires in the coop would sound a bell or buzzer and a soldier of the Signal Corps would know a message had arrived. The soldier would go to the coop, remove the message from the canister, and send it to its destination by telegraph, field phone, or personal messenger.

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