A group of researchers working in Montana’s Hell Creek Formation have discovered the fossilized remains of four different dinosaurs, including one that may be a new species.
Paleontologists, who come from the University of Washington and the Burke Museum, have discovered the ilium (or hip bone) of an “ostrich-sized theropod,” a group that includes carnivorous dinosaurs to two legs such as T. rex or raptor and the hips and legs of a duck-billed dinosaur.
They also unearthed a pelvis, a toe claw, and limbs from another theropod which could be the rare Anzu (also known as the âhell chickenâ) or possibly a new species; as well as the skull and other bones of a Triceratops.
Researchers have found the skull and other bones of a Triceratops. The “trailer hitch” or occipital condyle bone (pictured), connects the skull to the neck vertebrae
“Each fossil we collect helps us refine our vision of the last dinosaur-dominated ecosystems and the earliest mammal-dominated ecosystems,” said Gregory Wilson Mantilla, professor at the University of Washington and curator of vertebrate paleontology at the Burke. Museum in a press release.
“With these, we can better understand the processes involved in the loss and origin of biodiversity and the fragility, collapse and assembly of ecosystems.”
The discovery was made in Montana’s Hell Creek Formation, where a number of dinosaur fossils have been found over the years.
Located in the northeastern part of Montana, the area dates back to the latter part of the Cretaceous, between 68 and 66 million years ago.
A CHRONOLOGY OF THE HELLS CREEK EVENT
Researchers estimate that seismic waves struck the Hell Creek Formation within 10 minutes of the impact of the asteroid Chicxulub 66 million years ago.
These would have been the equivalent of waves from a magnitude 10 or 11 earthquake.
The team suspects an inland sea to have spawned at least two massive waves, called cuttlefish.
These beat the earth with only about 20 minutes in between, ultimately dropping more than six feet of deposits on the doomed creatures at the site.
All the while, deadly glass marbles called tektites were raining down from the sky like tiny ballistic missiles traveling at 200 miles an hour.
Fossil records show that these pearls continued to peel the surface for 10 to 20 minutes after the first wave, before a second hit and buried the stranded fish in sand and gravel.
This thick deposit was eventually sealed by a layer of clay rich in iridium – a material rare on Earth, but common in asteroids and comets.
The Hell Creek Formation, located in the northeastern part of the state, dates back to the latter part of the Cretaceous, between 68 and 66 million years ago.
A number of dinosaur fossils have been unearthed there over the years, including the triceratops known as âBig John,â which is expected to go up for auction next month.
It is also home to a cemetery filled with fish, mammals and another triceratops who died after being entombed by a tsunami triggered by the asteroid that struck Earth 66 million years ago.
The triceratops are known as the “Flyby Trike” after a breeder (who leases land from the Bureau of Land Management) spotted it while flying his plane.
To date, paleontologists have discovered the triceratops frill, horn bones, rib bones, lower jaw, teeth, and a bone known as a âtrailer hitchâ.
The âtrailer hitch,â or occipital condyle bone, connects the skull to the vertebrae in the neck.
Experts believe that around 30 percent of triceratops have been discovered.
It is likely that the “Flyby Trike” died in a floodplain because its bones were found on top of each other, differently from how a living animal would have been found.
It is also possible that the bones were moved by a scavenger, such as T. rex, before they were fossilized.
This Triceratops may have been one of the last of its kind living before the asteroid impact, with paleontologists at the University of Washington estimating that it lived less than 300,000 years before the impact.
âPrior to this year’s excavation, part of the Flyby Trike collar and a frontal horn were collected and then prepared by volunteer preparers in the fossil preparation lab,â said Kelsie Abrams, head of the paleontology preparation lab. from the Burke Museum which also ran the field this summer. job.
The triceratops are known as the “Flyby Trike” (pictured). To date, paleontologists have discovered the triceratops ruff, horn bones, rib bones, lower jaw, teeth, and a bone known as a “trailer hitch.”
Kelsie Abrams (photo), head of the Burke Museum’s paleontology preparation lab, opens the field jacket of a theropod ilion
âThe collar has been put together in many pieces and put together in a fantastic way by volunteers. After confusing the flying part together, it was discovered that the specimen is probably an older âgrandparentâ triceratops.
Abrams continued, âThe triangular bones along the ruff, called the ‘occipital spikes,’ are completely fused and almost unrecognizable on the specimen, compared to the sharp, noticeable triangular shape seen in younger individuals.
“In addition, the frontal horn curves downward rather than upward, and this feature has also been reported in older animals.”
Additionally, researchers found amber pods and seeds near the “Flyby Trike,” which will allow paleobotanists to determine which plants the dinosaur was eating and what the ecosystem looked like at the time.
âPlant fossil remains from this period are crucial to our understanding of the wider ecosystem,â added Paige Wilson, a UW graduate student.
“Not only can plant material tell us what these dinosaurs may have been eating, but plants can more broadly tell us what their surroundings looked like.”
The four fossils will eventually become part of the collections of the Burke Museum.
WHAT MAKES TRICERATOPS SO FURIOUS?
Triceratops were herbivores and had two large horns on their eyes and a smaller nasal horn, as well as a parrot’s beak and large ruff that could grow up to nearly one meter (3 feet) in diameter.
According to the Natural History Museum in London, UK, its horns could have been used to fend off attacks from Tyrannosaurus rex, one of its main predators.
A partial Triceratops fossil found in 1997 had a horn that had been bitten, with bite marks that correspond to T. rex.
Triceratops likely lived in herds to warn each other of danger and reduce their chances of being targeted by predators. Pictured is a reconstruction of what a Triceratops might have looked like
Puncture marks were also found on fossil flourishes showing that male triceratops also used their horns to fight, possibly to impress females.
The flourishes of triceratops could have been used to attract mates, or as a way for members of the same species to recognize each other or regulate body temperature.
Triceratops likely lived in herds to warn each other of danger and reduce their chances of being targeted by predators.