@Sheril
I volunteered on a couple dinosaur digs a long time ago and I asked the paleontologists there if they thought humans would be around in a million years. To a one they said "nope".
Chipping out a baby Parasaurolophus skull from solid rock, it was easy to imagine the wave upon wave of fabulous creatures that once roamed the earth at one time or another, only to become fossils by the time the next ones were leaving footprints in the sediments above them. In the future, in a length of time from now that is barely a rounding error in the last 4 billion years, Earth will be covered with another unimaginably weird and wild menagerie.
We're just messing it up for ourselves and the other creatures here at the moment. We could nuke ourselves 50 times over and the ecosystem from undersea vents would take over in a million years or two.
The idea that we're awesome enough to destroy the world is the same hubris that will lead us to destroy ourselves instead.