I WONDER HOW A JW WOULD ANSWER THAT QUESTION.
I've been out since 83. I think that a lot of people that defend creationism will acknowledge micro evolution, when I was a witness the witnesses refered to this as adaptation. Adaptation does not require the leap of faith to accept as Macro evolution which is evolution from and amoeba to a human being and evolution above the level of the species. Adaptation, micro evolution is used by creationist to describe what scientist see today, what everybody with eyes can see. Diet will make people in a region grow taller or shorter. But it takes faith to believe that a fish is going to crawl out of the sea and start walking as a man or that a man is going to crawl into the sea and live as a fish. To go beyond micro evolution aka adaptation is taking the same religious leap of faith as any other faith.
One definition of faith is believing in something that you just know isnt so. Scientist can say something is millions of years old but there is no way to know for sure as we dont know of anything that is a million years old to compare it too. So the first leap of faith is that the earth is a million years old or older and thats how they calabrate their dating machines. If man and the earth has always exhisted and if more advanced civilizations have exhisted there should be archelogical evidence. I havent heard of them digging up airplanes or tv sets that are thousands of years old.
I dont believe in the bible, But the science I believe in has to go by the scientific method and be capable of being demonstrated in a labratory. Anything less than that is joining another religion or cheering for somones hypothesis.
In my trying to make sense of where man came from, The theory that has the most tangible evidence, is that we were placed here, seeded by space people, Gods. The place I would offer to you to find tangible evidence would be to start with Eric Von Donakins "Chariots of the Gods" and also the writings of Zecharia Sitchin.
I think there is another dimension and the beings in the other dimension have designed and are manipulating the beings and bodies in this dimension and are probly amogst us inhabiting the bodies that they designed.
To me the exhistence and interface of this other dimension is why we can not make sense of our exhistence. Because most of science and most of man does not acknowledge it. Science does not acknowledge it because its exhistence can not be demonstrated by the scinefific method.
To answer your question as a former JW. Microevolution aka, adaptation.