Let’s think about what a fossil really is. A creature turned to rock, right?

For the lucky few that get immortalized (or nearly) by geology and chemistry, hard tissues slip away as minerals take their place, molecule by molecule. The ancient dinosaur, or crustacean or plant is wiped entirely from the face of the Earth, and in its place is a kind of negative image.

Negative, I suppose, in the sense that rock has replaced what once was living, breathing tissue, but also because the soft