In a way, being born is a sort of ecological contagion. When you have longevity of family, we remember our grandfathers and maybe our great-grandfathers. We somehow don't have the capacity in modern life to remember further than that. All of the ramifications of their lives have an effect on us, and we're not aware of it.
If children have an interest in nature, they will understand. I want them to become people who appreciate the consequences the next generation will suffer if we destroy our natural surroundings. So without a doubt, they need to learn that nature is vital to us by experiencing it. I want them to like nature and to climb mountains and so on.