A New Dinosaur Discovery

Sciworks Radio
Sciworks Radio
A New Dinosaur Discovery

Our knowledge and understanding of ancient life on earth is always expanding. It’s the job and passion of paleontologists (click here if you are a young kid) to piece together evidence and breathe new life into lost species and their environments. Dr. Lindsay Zanno, Director of the Paleontology and Geology lab at the Museum of Natural Sciences in Raleigh, North Carolina and Research Assistant Professor in the Department of Biological Sciences, at NC State University, has that passion. And I bet she was a lot like you or someone you know when she was a kid.

When I was in third grade I loved dinosaurs. Like most people, I grew out of dinosaurs. What I never grew out of was being a curious person, wanting to ask questions and then wanting to be the one to find the answers myself.

There’s a lot of confusion out there about what a dinosaur is (for kids). We talk about dinosaurs as if it means anything extinct, But Dinosaurs were very special group or reptiles that was very active in how they moved, very sophisticated and how they breathe, very intelligent for their time. If you think about a dinosaur, you’re probably going to think about a dinosaur that’s from the late Jurassic or the late Cretaceous (more dino times). So either about 150 million years old or when most dinosaurs went extinct about 65 million years ago (Learn about geologic time). Triceratops, Stegosaurus and T Rex; Some of the most famous dinosaurs. Although we know a lot about those time periods we don’t know a lot about the dinosaurs lived in between. So we launched an expedition to target dinosaurs that lived right in the middle that gap of our understanding. Those were dinosaurs that lived about 100 million years ago.

From this expedition, Dr. Zanno and her team from NC State (See co-discoverer from Chicago’s Field Museum) have identified an exciting new meat eating species. They named it Siats Meekerorum.

Siats (pronounced See-Atch) is an animal actually found the very first year we started this project. We had something big something new and something really important. We didn’t find a ton of the animal but we found portions of its pelvis, hind leg, tail and its back. And some teeth. The shape and size of the hind leg is a really good indicator of the size of the animal. We have no certainty about what the skull would look like. We look on the family tree and we have to make a best scientific guess that it looked similar to those things.

Putting it all together, Dr. Zanno has found an interesting and very impressive new dinosaur.

This animal was one of the top three predators in terms of its size that ever roamed North America. T Rex is still the biggest so far and then Acrocanthosaurus reigns in at number 2. Siats is right now number three, but the skeleton we found was a juvenile.

But Siats went extinct, and that was good news for one of our collective favorites.

Animals that are at the top of the food chain, we know, are very susceptible to extinction. At some point there is an extinction event here North America and these animals disappear. And then other animals that are living in ecosystem are able to evolve to fill those. And the story here is that once Siats disappeared they were smaller body tyrannosaurs, and they were able to fill that role by evolving giant size and becoming the top predators themselves.

Siats is from a completely different group of predators then tyrannosaurs are. They looked a lot like tyrannosaurs but they were not closely related at all. If you want to be a giant predatory dinosaur there’s pretty much one good way to do it. It’s a surprising thing about evolution but what works works, and when you become an animal that feeds in the same way or lives in the same ecosystem you tend to evolve structures that are good at those functions. And so you end up looking more similar than you do dissimilar.

This is a concept we call “convergent evolution.” We see it all over the natural world. Bats, birds and insects all evolved flight separately. Dolphins are mammals that swim like fish.

Siats Meekerorum… Where did that name come from?

This was the ancient land where the Ute tribal Nation lived, so we ended up choosing a name from one of their legends. And so Siats, it was the man eating monster. Meekerorum I chose to honor the Meeker family. Their contribution to helping young scientist is why we chose to honor them.