The similarities between bones of humans and other animals shows that every living creature on earth has a common ancestor, even if that common ancestor is as simple as a sing-celled organism.
Answer:
Primary succession is the orderly and predictable series of events through which a stable ecosystem forms in a previously uninhabited region. Primary succession occurs in regions characterized by the absence of soil and living organisms.
Many scientists agree that the universe is about 13 billion years old.
