I like the "Cult to Religion" diagram. The process of churches splitting to form new churches is very much like one species splitting into two, which can happen in this cult way (like a tiny founder population being stranded on an island), or the whole church can split over an issue, like most American churches did over slavery, and like some are doing now over homosexuality. Quite a few people have drawn evolutionary trees of all our modern religions, but this one by Simon Davies seems the most popular.