How often do you think about the ground under your feet? About what it is composed of or how old the rocks are? Did you know that under your feet, there are not just rocks and soils, but fossils? Most of Illinois’ exposed rock layers, and the fossils found in them, were formed during the Carboniferous, approximately 355 to 290 million years ago. Check out the Paleontology Portal’s website about Illinois’ paleontology and geology, http://www.paleoportal.org/index.php?globalnav=time_space§ionnav=state&name=Illinois.
The Chicago Academy of Sciences and its Peggy Notebaert Nature Museum (CAS/PNNM) has over 22,000 fossils in its collection, most of which were collected from sites in the Midwest. To celebrate National Fossil Day, here are some specimens from CAS/PNNM’s paleontology collection.
Macroneuropteris macrophylla, a Neuropteris-like group seed fern from the Braidwood flora of the Mazon Creek area, IL. Carboniferous, Francis Creek Shale.
Spirorbis sp. (on Stigmaria sp.), worms on root structure, from the Essex fauna and flora of the Mazon Creek area, IL. Carboniferous, Francis Creek Shale.
Lobatopteris lamuriana, a true fern from the Braidwood flora of the Mazon Creek area, IL. Carboniferous, Francis Creek Shale.
Hystriciola delicatala, an annelid worm from the Essex fauna of the Mazon Creek area, IL. Carboniferous, Francis Creek Shale.
Annularia sp. specimens collected by Jonathan H. Britts from Henry County, MO.
Pecopteris vestita, a fern leaf collected by Jonathan H. Britts from Henry County, MO.
Pentremites obesus, a blastoid from Anna, IL. Mississippian, Chester Limestone.
Platystrophia acutilirata, brachiopods collected from Cincinnati, OH. Ordovician, Cincinnati Limestone.
Conularia crawfordsvillensis, (animal) collected from Crawfordsville, IN. Mississippian, Keokuk Group.
Phillipsia bufo, a trilobite collected from Crawfordsville, IN. Mississippian, Keokuk Group.
Stop in at the Nature Museum for a visit to see fossils up close. Here are a few of the fossils you can find on display:
Mammut giganteus, mastodon mandible and tooth from Macon County, IL
Receptaculites oweni, fossilized coral collected from Galena, IL
Tremanotus chicagoensis, gastropod (snail) specimen from Bridgeport, IL
Lepidodentron aculeatum, fossilized bark collected in Orange County, IN
Calymene niagarensis, trilobite specimens collected from section 6 of the drainage canal, Chicago, IL
Want to learn more about the fossils under your feet?
Gugilotta, Guy. “The World’s Largest Fossil Wilderness.” Smithsonian Magazine, July 2009. [Smithsonian.com, http://www.smithsonianmag.com/history-archaeology/Phenomena-Forest-Primeval.html]
“How Do We Know? – Fossils” webpage on MuseumLink Illinois site. Illinois State Museum, 2000. [http://www.museum.state.il.us/muslink/forest/htmls/how_foss.html] Information about how fossil pollen is used to study past environments.
Wittry, Jack. Mazon Creek Fossil Fauna. Illinois: ESCONI and Northeastern Illinois University, 2012. * Includes photographs of specimens from the CAS/PNNM collection!