Newchapter,
Why you keep getting concerned about "god" is beyond me. It's as if the only other conclusion you can come up with to explain the novelty of biodiversity must be:
point mutations+natural selection/time
When an argument for a position fails, it doesn't win because of a philosophical position previously held, it wins because it has been demonstrated.
The second thing is that you speak of "science" as if "science" were a pristine angel, rather than a method.
There is no "science" in that matter of speaking, and there are no "scientists" either.
There is the scientific method, and people can engage in the use of this method.
QED.
If you'd like to learn more about the process I'd suggest two books:
1. http://www.amazon.com/Popper-Selections-Sir-Karl-Raimund/dp/0691020310
http://en.wikipedia.org/wiki/Karl_Popper
2. http://www.amazon.com/Structure-Scientific-Revolutions-Thomas-Kuhn/dp/0226458083
http://en.wikipedia.org/wiki/The_Structure_of_Scientific_Revolutions