Next time your son or daughter asks which kind of dinosaurs lived in Indiana millions of years ago, you can smile thoughtfully and say, “We really don’t know.”
It’s true. When it comes to dinosaurs dating to the Mesozoic or earlier, Indiana doesn’t have much to brag about in either fossils or knowledge, but when it comes to brachiopods and mastodons (clams and wooly mammoths), the Hoosier state rules…
In the Paleozoic Era (approximately 250 million years ago), a shallow sea covered Indiana, depositing an abundance of brachiopods, crinoids and trilobites. Large reefs systems covered the state as well, sometimes trapping organic matter to later become petroleum deposits.
Indiana isn’t known for its dinosaurs, but not because they didn’t live here. Between the Paleozoic and Mesozoic Eras, the shallow sea covering Indiana constantly eroded the bedrock. Any material that could have contained fossils was worn or washed away.
When the Potawatomi discovered the fossilized remains of wooly mammoths around Devil’s Lake (Lake Manitou in Rochester), they assumed the massive, odd creatures were the remnants of water monsters, earning the lake its forbidding name.
Lake Chicago, a massive glacier that covered northern Indiana and helped form the Great Lakes, is largely responsible for Indiana’s current topography (flat in the north, hilly in the south). 13,000 years ago the glacier retreated and eventually transformed into Lake Michigan.
The abundance of plant fossils discovered in Indiana (almost 150 species) have given them status as trace fossils, used to date prehistoric coral seams at other sites.
Indiana’s most popular prehistoric site, Falls of the Ohio State Park, contains a treasure trove of fossils from the Devonian Period (about 420 million years ago). It is also the location at which Lewis met Clark for their journey into the Western frontier.
Indiana fossil hunters have found several traces of the saber-toothed cat (a saber-toothed “tiger” is a misnomer). The famously-extended front canine teeth of this apex predator helped pierce the thick hides of prey, tearing apart flesh and blood vessels.
The dire wolf, another famous predator, also stalked meals across Indiana. Comparable in size to modern wolves, dire wolves had the most powerful bite of any canis (dog or wolf) species. The dire wolf died out about 13,000 years ago in the American megafauna extinction event, which most experts believe was caused by human overhunting.
Little is known about the Precambrian in Indiana, from the Earth’s formation to around 500 million years ago. The vast majority of the bedrock from the state at that time was igneous (or solidified from lava), preventing any kind of lasting fossil record.