So if the average bear can observe that DNA base pairs change at the rate of say a few hundred per generation on average, why can't he make the same straight line extrapolation to lead to the several million pairs difference seen between closely related species? It's exactly the same thing, with the exception that religious beliefs have led to the notion that there's some mysterious barrier preventing small changes to one species from leading to a new species. Once a new species has formed, then what's the barrier preventing it from changing and forming yet another species, and so on. The various species of life form a continuum. Maybe the average bear can't see this, but that's just because the entire continuum is not alive today; most of the species forming the continuum are extinct. The small changes observed in living organisms are not any different than the small changes in position of the continents or the small layers of dirt that are laid down in a rainstorm. The fact that the average person doesn't see this is irrelevant. The evidence is out there.
So if the average bear can observe that DNA base pairs change at the rate of say a few hundred per generation on average, why can't he make the same straight line extrapolation to lead to the several million pairs difference seen between closely related species?
:: Because the changes in base pairs don't necessarily add information. They can just as easily subtract or move sideways.