In the following interview, Dawkins categorically admits that
no one knows how life began, including evolutionary biologists. He has absolutely no answers when it comes to a First Cause of life.
It shows, I think, that most of the vitriol he spews has much more to do with his own anti-religious bias and opinion rather than actual research and application of the scientific method.
He goes on to say that life on Earth could have begun by the seeding of a "higher intelligence" or "intelligent design". Noting the fact Dawkins does not believe in God, this seems to
imply that he may believe in aliens and/or spacemen.
http://www.youtube.com/watch?v=GlZtEjtlirc