This ignores a basic truth of evolution. You think you can "choose" against children, for the environment. But that is not allowed. If you take that choice, lo

This ignores a basic truth of evolution. You think you can "choose" against children, for the environment. But that is not allowed. If you take that choice, long term, it'll simply result in others, presumably less ecologically conscious, doing it for you. Furthermore, one can easily argue that fluctuating numbers of animals is far worse than just large numbers of them. Animals will adapt to having larger numbers (by, for instance, shrinking their bodies). Fluctuating numbers, well, read the history of environmental protection at Yellowstone park for instance to hear what can happen.