Actually, JWs DO accept evolution. They believe--without critically examining how foolish it is--that all present living organisms are the offspring of the animals (sea creatures excepted) that were on Noah's ark.
This belief would require a much more aggressive and accelerated form of evolution than that posited by any evolutionary biologist. In other words, JWs and all other fundamentalist Christians believe in a form of evolution that took place in a few thousand of years instead of the many millions or even billions of years posited by evolutionary biologists. Let that sink in.
That being said, the important issue for JWs is not whether living things change over time--that well-established fact is unremarkable in the respect that it should have little or no consequence for a fundamentalist Christian of any stripe--but rather how life began in the first place: the origins of life.
How did life begin?
While biologists are certainly interested in that question and have some ideas, it is not directly related to the issue of biological evolution over the course of time since life's inception.
But the majority of JWs are not educated and/or intelligent enough to appreciate this very important distinction.
