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.
A sonar image of the shipwreck of the Soviet Navy ship Virsaitis in Estonian waters. Johan Christian Dahl: Shipwreck on the Coast of Norway, 1832. A shipwreck is the remains of a ship that has wrecked, which are found either beached on land or sunken to the bottom of a body of water. Shipwrecking may be deliberate or accidental. UNESCO estimates that worldwide over 3 million shipwrecks, some thousands of years old, lie on seabeds.