The fossil of a juvenile T. rex was accidentally discovered in North Dakota not by a group of trained paleontologists, but by three boys whose sole purpose for the day was to go on a hike.
According to the Denver Museum of Nature and Science, Sam Fisher, 45, took his sons, Jessin, 12, and Liam, 9, and their cousin, 11-year-old Kaiden Madsen, on a hike in the North Dakota Badlands in July 2022. While hiking, the trio of “young fossil hunters” discovered a rare Tyrannosaurus fossil, according to a news release from the museum.
Once they found the fossils, Sam Fisher called his high school classmate, Tyler Lyson, the museum’s curator of paleontology. Lyson plans to return to the site with the boys and a team of paleontologists to dig up the remains in the summer of 2023, according to the museum. It took a year to recover the fossils, because Lyson had to get permission from landlords to excavate them.
“By getting outside and engaging with their passion and the excitement of discovery, these boys made incredible dinosaur discoveries that advance science and deepen our understanding of the natural world,” Lyson said in the release. “We can’t wait for museum visitors to become engrossed in the Teen Rex Discovery experience.”
How big was a teenage T. rex?
By analyzing bone structure, growth patterns and bone histology, Lyson and a group of paleontologists were able to determine the dinosaur’s age at death and determine that the fossil belonged to a juvenile Tyrannosaurus rex, the museum said in a statement.
“Histological testing has not yet been performed but will be done in the future. Based on the length of the specimen’s tibia, we have estimated the size of a teenage T. rex,” the museum said on a Q&A page for a documentary about the discovery. “Given that our specimen’s tibia is 82cm long and that a full-grown T. rex’s tibia is 112cm long, our specimen is likely to be from a teenage T. rex.”
According to the museum’s Q&A page, paleontologists believe “Teen Rex” weighed 3,500 pounds, was 10 feet tall, and was 25 feet long at the time of its death. The exact weight of the fossil will be determined through further study and analysis.
By comparison, a fully grown adult T. rex could reach a length of more than 40 feet and weigh up to 8,000 pounds, the page states.
What can the fossil of a teenage T. rex tell paleontologists?
The museum says the young T. rex fossil is unusual because T. rex fossils discovered usually belong to larger, more powerful animals. The Q&A page says the young skeleton will allow researchers to study the growth and development of the T. rex during a “critical period” in its life.
“The story of Tyn Rex and his three children, Jessin, Liam and Kaiden, highlights the power of curiosity, determination and the pursuit of knowledge – a reminder that anyone, no matter their age, can make a big impact by following their passion and embracing the excitement of discovery,” the museum said.
Teenage Tyrannosaurus excavation site photographed, on display for museum debut
The discovery of the fossil was videotaped and compiled into a new 40-minute documentary titled “T. Rex,” which will be screened on June 21 in the museum’s giant Infinity Theater, according to the museum.
“Using cutting-edge CGI and cutting-edge paleontological insights, this big-screen film offers an unprecedented journey into the world of Tyrannosaurus and fellow Cretaceous carnivores,” according to a press release.
According to the museum, a special exhibit of a juvenile T. rex fossil called “The Discovery of Teen Rex” will also be open to the public on June 21, but will only be open from 1:30 p.m.
