Coprolite: A rock that was once food. Maybe humans-from-10-centuries-ago food, maybe dinosaur food from 80 million yeards ago, but all the same, food. That slightly blows my mind. Generally, unless you're Rock Biter or a Horta, rocks are not food. But if trees, mummies, dinosaur bones, mastodon hair and so much more can be preserved in this world, why not this world's excrement -- the once warm, odiferous, (you hope) reasonably soft excrement?
Huh. Zombies may, perhaps, develop coprolites. I just realized this. Who really knows how a body would function after that person's become a zombie? Perhaps what's left in such a body would turn into something much like stone. Maybe THAT is where coprolites came from. (You just imagined zombie dinosaurs. If your mind was blown, I apologize.)
This was an entry for therealljidol. It does not have very good interpretations of science.