Life was first formed in
The oceans of primitive earth
Earth was formed approximately 4.5 billion years ago. As it cooled down, a primitive atmosphere was created by the outgassing of early volcanoes. The early atmosphere contained no oxygen and could not support most of the life forms. In addition to the molten lava flowing into the ocean, some of the chemicals viz., hydrogen, helium, carbon dioxide, nitrogen etc. were supposedly washed down by the rains into the ocean where these chemicals gradually converted to simple organic molecules that eventually joined together into complex organic molecules like DNA and RNA. These chemical reactions made the ocean a reservoir of chemicals. Hence, it was known as the “organic soup”. Progressively, self-replication of simple nucleic acid molecules led to the origin of various simple life forms on Earth.