Fossils give us hints about what life and the environment looked like millions of years ago. A fossil is the remains of a dead plant or animal that lived a long time ago. Fossils usually consist of the remains of the organism itself. However, fossils may also consist of the marks left behind by the organism while it was alive, such as the footprint of a dinosaur or reptile.
For millions of years Iowa was under a body of water. Many of the fossils found in Iowa are sea animals or plants, such as the crinoid which is the state fossil of Iowa. These fossils can be found along rock outcroppings, stream beds, and rock quarries. It is illegal to collect any rocks or fossils from any Polk County park.