It is true that Darwinism is predicated on the survival of the fittest
paradigm, but Darwinism-- Evolution, equals not Creationism to begin with.
Think about it. Evolution is not the end all theory for the development of our planet the way Creationism predicates to be. Those who believe this are just simply incorrect. There are many other variables, more than we mortal humans probably realize, that guide the development of life on the planet, not just evolution. The Sun's history, Earth's orbit, Earth's rotation, it's axis tilt, it's nutation, it's precession... well, I don't want to get too technical because I'm not trying to pretend I know more than I really do know. But all of these and other factors have influenced Evolution (the development of life), what species survive and which don't. And life on Earth, according to our current knowledge, has come quite close a few times to total armaggedon, so the system is not 'godly' perfect.
I know some environmentalists like to preach that Mother Nature knows best. She knows better than us, but she does not know all. I equate them with capitalists: they believe The Marketplace knows best. Again, the marketplace knows better than us individuals, but it does not know all.
My point is, Humans are unlike anything that has ever existed on this planet, at least in the last 65 million years. We could adopt the philosophy of survival of the fittest and perpetually use Earth's resources for our benefit, but eventually that would probably lead us to extinction, or at least a population and civilization crash. Nature's way of saving herself, perhaps.
Others would say that since Humans can control their actions, protecting the rest of Earth's lifeforms is the other choice we can make. Nature's other way of saving herself, perhaps? Some would argue that philosophy.
The two options, literally, can be sourced by those who believe in Nature's wisdom, and by those who believe in God's absolute role in such process, of giving humans the power of choice being his way of rewarding OR
punishing ourselves by our own actions.