It's an occasional trope of science fiction -- you venture into the far future or to a parallel reality or under the sea only to find that some non-human species has evolved an entire human-like civilization. In these stories, Earth seems to be almost crawling with heretofore unknown peoples and races. I'm as big a fan of this sort of thing as anyone, but it derives from one mercilessly stubborn misunderstanding of evolution -- that it has a purpose, a goal, and that the goal is to eventually become civilization.
But get back in your time machine and jump back to the halfway point of Earth's history, about 2.3 billion years ago. You don't see forests. You don't see giant lizards. You see an apparently barren world. Evidence of life is subtle. Here, at the halfway mark of natural history, the only organisms on the entire planet are microbial -- bacterial mats, perhaps algae. And it has been this way for most of the entire first half of our planet's history. In another two billion years, the first multicellular animals will begin to appear, but for now, all is hauntingly quiet.
Consider this for a moment, really consider it -- a full three quarters of Earth's history saw no creature bigger than a protozoa. Neither tower nor tree rose up from the desolate expanses of bare rock. No ships nor sharks crossed the empty seas. No sunsets were witnessed. No songs were sung. No stories were told. No shred of civilization, nor any indication that there ever would be. For over three billion years, three times as long as the entire history of all animal life, bacteria was by far the most complex organism on the planet. That is, to say the very least, an astonishingly stable ecosystem.
It is sometimes said that we are unwilling to be accept the fragility of our human civilization, but I don't think that's the case. Often, we are too willing to accept it. We either believe the show ends with us, or we believe the event of our extinction will be followed by some new non-human civilization evolving to replace us, and perhaps even accomplishing all the things we couldn't. We aren't quite so obsessed with our own inevitability, but we do like to think music and art and poetry and philosophy are inevitable; that if it wasn't us who created the things we value, it would at least be something a lot like us. The notion that our stories and ideas are fragile is perhaps even more terrifying than the notion that we are fragile. To think that we are but a fleeting blur of activity bookended by eons of wilderness chills us to the bone.
And it should. It should terrify us. We are too willing to lay down and wait for an end to swallow us up. To value anything we've done -- sonnets or ballads -- is to value us. If we are endeared to an ode on the beauty of an ancient forest, then our duty is not only to nature, but to the heart that aches to describe it. We should behave as if we understand that the very best of what we are can indeed be lost and forgotten along with the worst, because when it comes to creatures so complex, it would seem Mother Earth creates no species twice.