Instinctive behavior occurs when an animal has a particular internal state while it is in the presence of a specific external stimulation called a releaser or a sign stimulus.
How many ships did the U-boats sink? During the war the U-boats sank about 2,779 ships for a total of 14.1 million tons GRT. This figure is roughly 70% of all allied shipping losses in all theatres of the war and to all hostile action. The most successful year was 1942 when over 6 million tons of shipping were sunk in the Atlantic.
But the ship still has a story to tell. The U.S. Navy decommissioned the 30-year-old frigate Tuesday and with it shut the back cover on one of the most significant -- yet little-heralded -- stories in U.S. military history. The Simpson was the last modern U.S. Navy warship to sink an enemy vessel in action. Of the 272 ships in the fleet now, only one ship can claim a similar honor: the USS Constitution, now a showpiece in Boston harbor, which sank British vessels in the War of 1812. JUST WATCHED.