By: Henry Wei

On July 31, 2022, Jessin Fisher, his brother Liam, and their cousin Kaiden Madsen went fossil-hunting in the Hell Creek Formation. This area, known for its rich deposits of dinosaur bones, was about to yield a rare treasure. They found the largest juvenile T. rex in the world!

The discovery began when Liam and his father, Sam Fisher, saw a bone sticking out of the ground. Liam told The Washington Post, “My dad hollered for Jessin and Kaiden to come, and they came running up on the butte. Dad asked, ‘What is this?’ and Jessin said, ‘That’s a dinosaur.'”

Afterwards, they sent a photo of the fossil to Dr. Tyler Lyson, a paleontologist at the Denver Museum of Nature & Science. He initially thought it was a duckbill dinosaur so they did research and it turned out to be a T. rex. The bones were encased in a piece of limestone, so it took 11 days to excavate them. The researchers estimated that the T. rex was about 25 feet long, 10 feet tall, and weighed 3,500 pounds. They believe it was 13-15 years old and died 67 million years ago.

The T. rex fossils were displayed at the Denver Museum on June 21, 2024. The exhibit was named “Discovering Teen Rex.”, probably because the people who discovered them were teens. This discovery will allow researchers to study more about juvenile T. rex specimens and compared them to other adult trex.