Here’s Why Very Few Dinosaur Fossils Have Been Found in Iowa

When you think of Iowa, you probably imagine vast fields of corn and soybeans, rolling hills, and charming small towns. However, Iowa’s prehistoric past is a completely different story—one where much of the state was underwater, and the landscape was populated by extraordinary creatures. Let's embark on a time-traveling adventure to explore the prehistoric animals that once called Iowa home, and uncover some surprising dino-mite facts along the way!

Dinosaurs in Iowa: A Rare Find

Despite being part of the land of the dinosaurs during the Cretaceous period, Iowa’s fossil record is scarce. This is because much of the state was submerged under water, and subsequent glacial movements, showcased by the driftless region, disrupted existing fossil deposits and sediment. However, a few dino-mite discoveries have been made in our great state.

Hadrosauridae: The Duck-Billed Wonders

• Guthrie County (1982): Paleontologist Brian Witzke discovered small bone fragments of a hadrosaur, but they were too fragmented to identify the specific species.
• 2000 Discovery: Charlie Gillette unearthed a hadrosaur vertebra, making it the first identifiable dinosaur bone found in Iowa.
• Akron (1930s): John Holdefer's discovery of another vertebra—used as a doorstop by his daughter—was later identified as belonging to a large hadrosaur.

These discoveries suggest that duck-billed dinosaurs, some potentially as long as 30 feet, once roamed Iowa.

Beyond Dinosaurs: Other Prehistoric Marvels

While Iowa’s dinosaur discoveries are few, the state boasts a variety of other prehistoric creatures that are just as fascinating.

• American Mastodon: These elephant-like giants roamed Iowa during the Pleistocene epoch. Mastodon fossils provide a glimpse into a time when Iowa's landscape was far more diverse.

• Woolly Mammoth: In 2010, a farmer in Oskaloosa discovered a four-foot-long femur belonging to a woolly mammoth. You could say this discovery was mammoth-ly important for understanding Iowa’s prehistoric past!

• Plesiosaurs, The Okoboji Lake Monster: Iowa’s ancient seas were home to these long-necked marine reptiles. While the state’s plesiosaur fossils are less impressive than those found in neighboring Kansas, they still provide a peek into Iowa’s underwater world.

• Whatcheeria, The Water-Loving Tetrapod: Discovered by a geologist from What Cheer, Iowa, Whatcheeria is a prehistoric, semi to mostly aquatic, animal. The fossil was found in Delta, Iowa. This creature spent most of its time in the water, only occasionally venturing onto land. It’s one of Iowa’s more unique fossil finds.

• Corals and Crinoids, Iowa’s Ancient Reefs: If you’ve ever taken a trip to the Devonian Fossil Gorge in Coralville, you’ve seen and even walked on these guys. During the Devonian and Silurian periods, Iowa was submerged under ancient seas teeming with life. Fossils of corals and crinoids highlight this vibrant underwater ecosystem.

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Future Iowa Fossil Discoveries

While Iowa may not be the first place that comes to mind when you think of dinosaur fossils, its rich prehistoric past is a treasure trove waiting to be unearthed. With ongoing, farming, excavations, and research, who knows what other dino-discoveries lie beneath that corn or soybean field? Each fossil find adds a piece to the puzzle of Iowa’s ancient world.

So, while Iowa may not have been "Jurassic Park," take a moment to imagine our ancient seas and the incredible creatures that once roamed our “lands.” After all, that "cool rock" might hide a piece of ancient history.