Theories to explain life's origins

THE BIBLE:Genesis, the first book of the Bible, says God created the Earth, plants, animals and man all in six days. Christian fundamentalists read this as the literal explanation for life's origin and say scientific theories such as evolution cannot be true. This view is called creationism. The main Christian denominations interpret Genesis as an allegory on how God created life and accept the scientific theory of evolution as an explanation of how living species developed. This view is known as "theistic evolution."

DARWIN:Charles Darwin (1809-82) was a British naturalist whose theory of evolution founded modern evolutionary studies. His 1859 book "On the Origin of Species by Means of Natural Selection" argued that organisms with more favorable traits were more likely to survive and reproduce. His 1871 book "The Descent of Man and Selection in Relation to Sex" derived the human race from anthropoid ancestors related to the descendants of the orang-utan, chimpanzee and gorilla.

NEO-DARWINISM:This further development of Darwin's theory emerged in the 20th century as scientists added insights from new discoveries, especially Gregor Mendel's theory of genetics. Supporters say this updated version of evolution is one of the most solidly based theories.