The funny thing is while we're towards the tail end of life on earth in general, we're pretty much smack-bang in the middle of what we'd consider complex life.

The funny thing is while we're towards the tail end of life on earth in general, we're pretty much smack-bang in the middle of what we'd consider complex life. Multicellular plants are about a billion years old, and the entire kingdom of Animalia (including all vertabtrates, arthropods, molluscs, worms, etc) only crop up in the fossil record about 600 million years ago. The preceding two billion years were basically nothing but single celled organisms, phytoplankton, and simple eukaryots. Those guys will probably still survive us, but not for as long as they preceded us.