Now heres a model from the radical fringe. On the face of it it is simple, two dissimilar species become more similar. How do they do this? Perhaps they are responding to the same selective forces of a shared resource. The next logical step takes us to the margins of acceptable science. For example, Why did marsupial wolves look like placental wolves. Was there perhaps some archetypal "wolfness" of form and function that defined the limits to the solution. Another example: I am working on hummingbird pollinated plants and trying to determine if they are a complex of sister taxa who just happen to still share a pollinator, or if they are a group of unrelated taxa who are all adapted to the needs of life with hummingbirds. This kind of process seems to be being talked about in terms of Chaotic attractors in Complex Systems Theory. I have no idea where this thread is going to lead!.