Charles Robert Darwin theory of evolution by natural selection suggests that animals and humans shared a common ancestry. So, according to him, we were not created by God, we evolved from a primitive life form. Darwin formulated his bold theory in private in 1837-39So. His views were based on fossils he found in various places in his voyages around the world. He wrote the book "On the Origin of Species" (1859). Let his non-religious Theory of Evolution by Natural Selection (On the Origin of Species) be what it is... A theory, not a proven fact. Many serious scientists, after studying the human DNA, the complex designs of matters, the universe, etc, etc, had been convinced that a Creator does exist. Science is still in its infancy, we know very little about life and the universe. But the more we learn the more we will become assured of the existence of the supernatural or divine Creator God. The Bible was not written to prove the existence of God. The authors of the Bible wrote it with the knowledge that God does exist. The existence of God is to be accepted by faith. But this does not meant that there is no proof of His existence. In addition to the biblical arguments for God's existence, there other arguments. The cosmological argument states that an effect must have a cause. To every effect there is a cause. Nothing simply pop up out of nowhere. So this universe and everything in it is an effect. The teleological argument states that since the universe displays such an amazing design, there must have been a divine Designer. Besides these we know God exist because of the ways He had touched and so miraculously changed our personal lives with His love and grace
It is based on one maniacs mental rantings. He was a drug addict.
It's based on common sense and observation of the world around us. The basic concept is a combination of random mutation and natural selection of those mutations which improve the survivability of the species.