Evolution is the theory by which living creatures acquire and pass on randomly-acquired new traits from generation to generation, affecting the overall make-up of the population and even leading to the emergence of new species. This theory, first proposed by Charles Darwin, led to the generaly accepted scientific theory that humans evolved from earlier pre-human primates. During the early 20th century most scientists believed that humans evolved from separate groups of primates independently in Asia and Africa. In the last few decades scientific opinion has shifted and it is now generally believed that all humans can trace their ancestry back to a single man and a single woman, from Africa. Some Christians strongly oppose the theory of evolution as incompatible with Scripture, others take