Like, think about how the dinosaurs were around for literally like hundreds of millions of years, and yet we only have like thousands of fossils. And what are the possibility of a fossil existing from a civilization, like a fossilized human being from a civilization 200,000 years ago? It's almost none. Most things never become a fossil. It has to be like the perfect conditions to create a fossil. And so we don't really know what animals did or didn't live here other than fossilized ones. And that's a tiny fraction of what we find.