Hi there,

I would like you to correct me if I'm wrong  but here is how I see the mechanism of evolution:

Natural selection favors or selects for the more/most viable combinations from an existing gene-pool, but new genes don't appear through natural selection. As I understand new genes are produced by duplications (gene duplications) followed by other mutations.

Is it safe to say that new genes are generated only by mutations? 

Thank you

Not exclusively.

This is a good article to read:

http://www.nature.com/scitable/topicpag … ogenes-835

Do post again if you have further questions.