Trace fossils are marks of a creature’s everyday activities left in hardened sediment.. The actual living thing is no longer there, but the fossil is made from its markings. These can be things like the footprints from a dinosaur, impressions from leaves, paths made by clams, or burrows made by worms. A special kind of trace fossil is fossilized “poop” called coprolite. This waste material has turned to rock, so it doesn’t smell, and it won’t come off in your hand if you touch it. Coprolite can be studied under a microscope and may even reveal the contents of the organism’s last meal.