HORSE has been the most widely-used animal throughout the
recorded history of warfare as a mean of transport and to carry lightly
armored skirmishing forces

ELEPHANTS were used as mounts, or for moving heavy loads.

CAMELS were used as mounts in arid regions.

MULES to carry supplies and equipment over difficult terrain.

PIGEONS are exploited since the time of the French Revolution, for carrying
messages.

MARINE MAMMAL such as dolphins and sea lions, are being used by The U.S.
Navy for underwater sentry duty, mine clearance, and object recovery.

DOGS with explosives strapped to their backs were used during World War II
in the Soviet Army as anti-tank weapons. In other armies, they were used for
detecting mines, sentry duty, messengers and to spot snipers or hidden enemy.