|MadSci Network: Evolution|
The answer is, your guess is as good as anyone's. Evolution is a random process, driven by the environment in which an organism exists. Change the environment sufficiently, and an organism will either have to adapt to it or perish. Thus it has always been. We 20th century humans have found a way to circumvent the process to a degree - by controlling our environment, we limit the degree of change our species is exposed to. However, we are still not immune. Even though we can moderate environmental forces to some extent, we still do not have the capacity to survive major geological or climatological upheavals. And in a subtle way, we may be our own undoing. Just as the stromatolites of prehistory poisoned themselves by filling Earth's atmosphere with oxygen (thereby making life possible for the animal kingdom), we are filling it with carbon dioxide, methane, and nitrogen. As well, at least in the West, we are allowing, through medical intervention, genes for such things as spina bifida, cystic fibrosis, and other diseases which normally kill, to accumulate in our gene pool. What effect is this having on the survivability of our species? Who knows?
Try the links in the MadSci Library for more information on Evolution.