The most complete dinosaur fossil ever found in Mississippi, which state officials called “incredibly rare,” remains 85 percent underground since its discovery in 2007.
Paleontologists have confirmed that the specimen was a once-living hadrosaur, a family of herbivorous, duck-billed dinosaurs that lived more than 82 million years ago.
But experts say there are at least 61 recognised species of hadrosaur, a huge family of huge, herbivorous animals, and that hundreds of unique species may have once roamed the Earth.
Researchers managed to secure part of the specimen’s spine, as well as a forearm, a leg and a pelvic bone, but the rest of the specimen proved difficult to excavate outside Boonville in the northeastern part of the state.
“This rock had been lying around for a while because there was no one to work on it,” said James Stearns, a state geological officer.
Hadrosaurs are a large family of giant herbivorous dinosaurs with at least 61 identified species, and possibly hundreds of unique kinds that once roamed the Earth, according to experts. The hadrosaur above is an artist’s recreation of one such hadrosaur found in Russia.
The most complete dinosaur fossil ever found in Mississippi has been identified as a hadrosaur, but only 15 percent of it has been safely excavated. Researcher Derek Hoffman (above) undertakes 3D forensic bone analysis to identify the exact hadrosaur species.
For nearly two decades, it remained a mystery as to which of the many types of hadrosaur the fossil unearthed in the Boonville area of Mississippi belonged to.
But researchers are now turning to 3D methods of forensic bone analysis to solve the mystery before the bones are fully exhumed.
Derek Hoffman, a geology graduate student at the University of Southern Mississippi (USM), is now using this technique, known across multiple scientific disciplines as “geometric morphometrics,” to analyze hadrosaur fossils.
“What geometric morphometrics does,” as Hoffman succinctly put it, “is take a shape analysis approach.”
Key features or “landmarks” are determined for a given bone sample, and the distances between each and the ratios of those distances are compared via complex statistical models to ascertain differences and similarities with known bones.
This method has proven useful not only in anthropology but also in the study of human evolution, for example in comparing human brain cavities. Ancestors of modern humans and Neanderthals.
But Hoffman’s efforts to find answers about the hadrosaur fossil are made more difficult by the fact that parts of the creature are in the hands of private collectors.
Above is the humerus of an ancient hadrosaur discovered in northeastern Mississippi.
Hoffman’s research focuses primarily on bones on display at the Mississippi Museum of Natural Science.
“We have quite a few vertebrae,” George Phillips, the museum’s curator of paleontology, told the local paper. Clarion Leisure“There is one humerus.”
“There’s one ulna. The ulna is the back part of the forearm.”
“There are some leg bones,” Phillips continued, “and a pubic bone.”
The ulna of an adult hadrosaur is roughly two feet long, the humerus is about a foot and a half long, and the total weight of just one leg bone of an adult hadrosaur can easily exceed 50 pounds.
However, the most unique feature that distinguishes hadrosaur species – dinosaur skulls – remain undiscovered, much to the frustration of researchers.
It is well known that different species of hadrosaur evolved with a wide variety of strange crowns on their duck-billed heads, including a soft material that resembles a rooster’s red “crown.”
Paleontologists are still debating what biological purpose these unusual and sometimes flashy features may have served, but their variety contributes to the recorded diversity of hadrosaurs.
USM’s Hoffman focused on the dinosaur’s pubis (the front bone of the pelvis) as his next best option for identifying the fossil’s species.
The differences in the pubic bones of hadrosaurs are subtle and too subtle to be detected by the human eye, but rigorous mathematical approaches such as geometric morphometrics can reveal the hidden differences.
The USM geology graduate student hopes that the Mississippi fossil will at least narrow down the number of possible hadrosaur species.
Or, in Hoffman’s words, “Can we get this hadrosaur to the lowest level in the taxonomy?”
What we currently know about this hadrosaur is that it was about 25 to 26 feet long and stood about 16 feet tall on its hind legs.
Hadrosaurs are “arguably the best-known dinosaurs in the fossil record,” Hoffman said. Here’s an artist’s impression of another duck-billed dinosaur from this group, discovered near Texas 80 million years ago.
Although researchers believe the hadrosaur lineage began in North America, the herbivorous dinosaurs eventually migrated all over the world, with fossils found in Asia, South America, Europe and North Africa.
“They’re the best-known dinosaurs in the fossil record,” Hoffman said, “without question.”
The name Hadrosaurus comes from the ancient Greek meaning “stout lizard,” and this heavy animal was actually Approximately 2.2 to 4.4 US tons (or 2,000 to 4,000 kilograms).
Most hadrosaurs lived during the Late Cretaceous period, between 75 and 65 million years ago.
Other examples of hadrosaurid dinosaurs include: Parasaurolophusis a dinosaur with a long, backward-curving crown on its head that appears in the 2022 film Jurassic World Dominion. Edmontosaurusit had the aforementioned crown made of soft tissue like a cock.
James Stearns, a Mississippi Department of Environmental Quality bureau of geological sciences, said the discovery of the hadrosaur near Boonville in 2007 was “a perfect omen for the discovery of the hadrosaur.”Incredibly rare.”
“We don’t have much of a skeleton,” Stearns said. “We have bits and pieces, but we don’t have a skeleton.”
Stearns is hopeful the project will one day be completed, even though it’s taken nearly two decades to unearth even a small portion of the hadrosaur’s remains.
“The specimen is still being collected,” Stearns said.