Tumble Science Podcast for Kids · Tumble Media

The Dino Butt Fossil

October 17, 2025·25 min·2 clips

Inside the dinosaur butt fossil, scientists found mineralized poop—a clue to its anatomy.

This episode of Tumble Science Podcast for Kids explores the discovery of the first known dinosaur butt fossil. Hosts Lindsay and Marshall investigate a young listener's question about whether dinosaurs sniffed each other's butts. They consult biologist and "butt expert" Dr. Diane Kelly, who lives near them and studies animal anatomy. The fossil in question belongs to a *Psittacosaurus*, a small, dog-sized relative of Triceratops. Paleontologist Jacob Vinther discovered the exceptionally preserved skin impression around the dinosaur's vent, or cloaca. The fossil was flattened over time, requiring digital tools to "reverse squish" and reconstruct its original shape. Inside, researchers found fossilized poop, confirming they were examining the correct area. Diane Kelly created the first scientific "butt inventory" by photographing and dissecting modern animal cloacas from snakes, turtles, and birds. She also observed live chickens, the closest living relatives to dinosaurs, for comparison. A key insight was that the *Psittacosaurus* cloaca had a darker, bullseye-like opening, suggesting it could have been flashed for visual signaling. The fossil also showed mounds in positions similar to the large scent glands found in crocodiles and alligators. These glands release smelly materials used for communication in water. The researchers concluded this dinosaur likely used both visual displays and scent from these glands to communicate. A paleo-artist's illustration depicted one *Psittacosaurus* checking out another's raised tail, much like dogs interacting. This provided strong evidence that at least this dinosaur species could have sniffed each other's butts. The episode is educational and playful, balancing scientific detail with humorous asides about cookies and butt jokes. It uses a conversational interview style between the hosts and the scientist, making complex anatomy accessible. Young listeners curious about dinosaurs, animal behavior, and unusual scientific careers will enjoy this episode. Anyone seeking a straightforward, serious paleontology lecture might find the lighthearted focus on butts less appealing.

As heard by us

A dinosaur butt fossil becomes a clear, playful lesson in anatomy.

Tumble turns a silly listener question into a science story about dinosaur butts. It starts with what the hosts call the first ever known dinosaur butt fossil, then follows the researchers as they use digital imaging to virtually blow the fossil back up and identify a…

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You want a dinosaur butt fossil story that is funny, weird, and still real.

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