Meet the dinosaurs who roamed America

Millions of years ago, dinosaurs stomped across the land that would someday become Cedar Rapids, Iowa City and the rest of the Hawkeye State.

According to the Iowa Geological Survey, only a few dinosaur fossils have been found in Iowa, but many have been found in our neighboring states of Nebraska, Minnesota, Missouri and South Dakota. Even more have been found in other parts of the country.

So what sorts of dinosaur fossils have been found here and nearby, and what do they tell us about the massive creatures that used to dominate the Earth?

Hadrosaur

What's the proof? A fossilized dinosaur leg bone was discovered in 1928 in Decatur, Nebraska, a town very close to the Iowa border. We don't know yet exactly what species of dinosaur it came from, according to the Iowa Geological Survey, but scientists have determined it's from an ornithopod, a suborder of dinos that ate plants and walked on two legs.

How big was it? The size of the bone found indicated the dinosaur was 32 feet long, about the length of a telephone pole.

Tell me more. The fossil most likely belonged to an early Hadrosaur. Hadrosaurs had bills like ducks, and they weighed thousands of pounds. They lived during the Late Cretaceous period, which ended about 66 million years ago.

Triceratops & Tyrannosaurus Rexes

What's the proof? A Montana rancher who calls himself the Dino Cowboy helped find a nearly complete skeleton of a Triceratops in the eastern side of the state in 2006. Soon he realized the fossil was actually of two dinosaurs - a triceratops and what looked to be a young T-Rex.

How big were they? Before they grew into the apex predators we know, juvenile T-Rexes were much smaller and are thought to have had arms long enough snatch prey. Triceratops were plant eaters and grew to be about 9 feet tall.

Tell me more. The T-Rex and the Triceratops fossil, dubbed the Montana Dueling Dinosaurs, appear to have died together in the middle of a fight. The Triceratops' skull looked like it had been kicked, according to The Guardian, and there were teeth lodged in the spine of the carnivore.

Alamosaurus

What's the proof? A graduate student named Dana Biasetti found enormous dinosaur bones sticking out of a hillside in Texas in 1999. According to the National Park Service (she found the bones in Big Bend National Park), an excavation uncovered ten vertebrae of an adult Alamosaurus.

How big was it? HUGE. They were so big they had to be excavated by helicopter. Alamosauruses were herbivores whose necks and tails were super long. The one found at Big Bend was 100 feet long. That's longer than a basketball court.

Tell me more. Scientists believe Alamosauruses migrated to North America from South America by traversing the Isthmus of Panama. The first one was discovered in New Mexico in a geological formation called Ojo Alamo, according to McGill University, and that's how it got its name.

Comments: molly.duffy@thegazette.com