In addition to telling us that we were all going to burn up from acid rain and holes in the ozone layer, environmentalist indoctrination in the elementary school science classroom also dedicated a significant amount of time to discussions of endangered species. We were told that the ecosystem is an intricate web where every time a species went extinct, a link in food chain was broken and the ripple effect would jeopardize the viability of the entire system, including humans.
But haven't species been going extinct for billions of years, and haven't new species been taking there place? Isn't this part of evolution? When did we become vain enough to believe it our duty to maintain the status quo? Why should I really care if a polar bear goes extinct?
I think the world has bigger fish to fry: poverty, oppression, disease. I'm sure the starving kids in the Third World are real thrilled with the amount of time and resources we expend on worrying about endangered species.