Missouri made the crinoid its official state fossil. Nicknamed the "sea lily," crinoids are actually formed by ancient sea animals. What present day animals are they related to?

The Eastern goldfinch is Iowa's state bird, and the wild rose is the state flower. Iowa's official rock is the geode, and the oak is the state tree.

Now a group of seven Democrats in the Iowa Senate is stepping forward with a new proposal. They want to recognize the fossils of crinoids, which are marine invertebrates abundant in the rock of marine origin underlying the state, as the state's official fossil.

The lawmakers, led by Sen. Joe Bolkcom, D-Iowa City, have introduced Senate Joint Resolution 2001, which they believe would pay proper homage to the role of crinoids in the geological and paleontological history of Iowa. Bolkcom said he was approached by some of the state's leading geologists in Iowa City to pursue the measure.

The crinoid, also referred to as the sea lily, has survived about 500 million years of Earth history, according to the resolution, and the crinoids skeletal fragments make up a significant portion of Iowa's limestone deposits. This limestone is used for road base, as agricultural lime, as building stone, and as a component in concrete.

"This bill won't cost us a dime," Bolkcom said. "And I hope it will recognize the important of crinoids in the state's development. You know, when you think about all the building materials in the state's development, we couldn't do without the crinoid."

Sen. William Dotzler, D-Waterloo, who has a degree in biology, is a co-sponsor of the measure. He talked enthusiastically about the significance of crinoids in Iowa's ancient history.