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Since the first dolphin was trained by the United States Navy in 1965 to help divers in their underwater home, Sealab II, many other dolphins have been drafted into the Navy. Originally dolphins were used as messengers or to answer calls for help. Today dolphins do much dangerous and necessary work as locating explosives hidden in the sea and helping ships navigate safely in war zones.
Navigation can be safe thanks to dolphins ... .
finding mines
catching sharks
diving signals
diving
carrying ships