God allows death to enter the world. God sends a worldwide flood, saving only Noah's family and selected representative animals. God scatters the growing population at Babel by confusing their language. People and animals spread across the earth.
Physical separation leads to the formation of different races and cultures.
From then until now the world has been in a state of decay, both physically and morally. Adam and Eve lived for a long time had many children. The children married each other, but this was ok at the time, as they were no genetic imperfections yet. But in the very first family, Cain kills his brother Abel, and all the people in the world become bad, except for a man named Noah, and his family. God sends a worldwide flood as punishment.