On the other hand, standard, or open pollinated varieties are more or less stabilized in their characteristics. They remain fairly consistent, producing seed that will grow into plants more or less like their parent plants, though less uniform than hybrids.
The rank of admiral (or full admiral, or four-star admiral) is the highest rank normally achievable in the U.S. Navy. It ranks above vice admiral (three-star admiral) and below fleet admiral (five-star admiral). There have been 262 four-star admirals in the history of the U.S. Navy. Of these, 221 achieved that rank while on active duty, 40 were promoted upon retirement in recognition of combat citations, and one was promoted posthumously.
With 10 aircraft carrier groups, dozens of destroyers, 22 cruisers (nearest rival Russia has five) and a large modern submarine force, the US Navy rules the seas. This blue-water branch of the US military is run by more than 320,000 people and is also the owner of the largest warships in the world.