The factor which most importantly affected Paleolithic humans' lives was caleld th agricultural revolution - this was a period in history when people first started growing crops and figured out at that growing crops enabled them to have and eat more food.
There haven't always been nine justices on the court. The U.S. Constitution established the Supreme Court but left it to Congress to decide how many justices should make up the court. The Judiciary Act of 1789 set the number at six: a chief justice and five associate justices.
