 Carl Sagan had said that we are made of star stuff. So everything that we are made of is made up of this earth. And this earth is made up of star stuff. The dirt is made from star stuff. The dirt is made from comets that have made and passed through here. From comets that destroyed dinosaurs to the comets we see in the sky every year. And the Martian dust or whatever dust comes out of the sky, we see it. And it continues to accumulate on this planet. And we don't realize it because we just don't see it. And that's what the evolution process is.