Thanks - your answer is reasonable. What I was really looking for is a mechanism that demonstrates this: "Animals appear to be delineated by clear species simp

Thanks - your answer is reasonable. What I was really looking for is a mechanism that demonstrates this: "Animals appear to be delineated by clear species simply as a function of our perspective from a single time slice. If we could observe gradual change over millions of years, we would see many splitting branches and merging branches, branches that get further apart and then seed an explosion of many smaller branches (i.e. when say land animals split from birds), etc etc." The idea of gradual change is fine to me - and the term species seems to create too much confusion. But the fact that gradual change over time can create seemingly distinct states (lets not call them species) still boggles me mind when I try to conceive of the mechanism. Is asking that question a red-herring or completely unreasonable ? In fact that is the part I find most fascinating. The fact that the change was gradual doesn't preclude from the fact that this gradual change did lead to states which were observed to be quite distinct. One doesn't preclude the other. To explain more of where I am coming from: As a person who writes reasonably complex software for a living, I am amazed by the "software" in the brain if you will i.e. its remarkable cognitive capacity for many tasks that we are still in the process of replicating in AI. I find it hard to understand how this could arise as a step by step gradual change purely aided by a favorable set of environmental properties. So something to that effect would be really cool to understand (And even emulate or copy in our software development practices). I am a bit disappointed that there are no simulations that can be done or we don't understand the mechanisms well enough to do this. For a very specific example, it would be cool to simulate "This is how the eye came into being.". Not just enumerating the commonalities between eyes of different species - I find the "commonality" argument as being "factual evidence" of origin of the eye very weak personally. I know its been accepted as fact by most or everyone else but something that would demonstrate the underlying "gradual" principles at work to evolve an eye for example would be uber-cool and satisfying in my book. I don't understand why this question is stupid or or unscientific.