We humans are one among millions of separate species who live in a world burgeoning, overflowing with life. And yet, most species that ever were are no more. After flourishing for one hundred fifty million years, the dinosaurs became extinct. Every last one. No species is guaranteed its tenure on this planet. And humans, the first beings to devise the means for their own destruction, have been here for only several million years. We are rare and precious because we are alive, because we can think. We are privileged to influence and perhaps control our future. We have an obligation to fight for life on Earth — not just for ourselves but for all those, humans and others, who came before us and to whom we are beholden, and for all those who, if we are wise enough, will come after.