The middle finger nail grows the fastest. Interracial marriage in the United Sates was banned in 1664 and not overturned until 1967. The Guiness World Record for smallest dog is held by a 3.8 inch tall Chihuahua named Milly. When animals sleep through a cold period it's called hibernation, but when animals sleep through a hot period it's called estivation. The most common time to be born is 8 a.m. on the dot. The least common is 3:09 a.m. The oldest university in North America was founded in 1551. It's the National University of Mexico, founded by King Charles I of Spain.