The chance of finding larger fossils by this method is not good because the rock brought up from underground during drilling is usually crushed into small pieces. Much of what we know about life before the Mississippian Period comes from fossils found in areas outside of Kansas. Brachiopods, small-shelled marine animals, were abundant in Kansas seas more than 250 million years ago. Nonmarine plant and animal fossils also have been found in Kansas, but they are not as common because plants and animals often decay on dry land before they can be fossilized. Usually only fragments of bones or teeth are fossilized, and only a small number survive over millions of years.
Paleontologists compare new fossil finds to other fossils and to living animals.
This helps them determine what animals looked like millions of years ago.