Hacker News Reader

"Inherit the Stars" by James Hogan is a good scifi story about this.

Also "The Hab Theory" by Allan Eckert.

I really enjoyed the whole Giant series by Hogan.

Star Trek Voyager had an episode with the idea of an ancient saurian species that left earth many millions of years ago. https://en.wikipedia.org/wiki/Distant_Origin

Did that come first or did Doctor Who do it first?

I think TNG's The Chase is yet more interesting; it's also a shame its plot was never pick up again by series creators. https://en.wikipedia.org/wiki/The_Chase_(Star_Trek:_The_Next...