Paleontologists working in Utah have stumbled upon a remarkable Cretaceous scene preserved in sandstone. It appears that an entire pack of Utahraptors — a species closely related to Velociraptors — got stuck in quicksand and died together while hunting.
Illustration: Julius T. Csotonyi.
As Brian Switek reports in National Geographic, the discovery shows that the Jurassic Park movies may have gotten it right — raptors do in fact work together to chase down prey. The discovery of six Utahraptors and one Iguanodont, a bipedal herbivore, packed tightly into a small space presents an intriguing piece of evidence to this long-standing debate.
Switek describes the "Dinosaur Death Trap" and how the drama may have played out:
An unwary iguanodont stumbled into the quicksand, bellowing and struggling. If this didn't attract carnivores, then "that nice meaty smell would have," [paleontologist James] Kirkland says, like flies to flypaper. One Utahraptor after another tried to nab an easy meal and only ended up getting stuck, adding to the deathly aroma.
"We believe it's going to be the first example of dinosaurs trapped in quicksand en masse in the fossil record," Kirkland says.
The dinosaurs were encased in a small area, and in some places the fossils were stacked three feet thick. It's conceivable that they died at different times as they fell into the "dewatering feature," or what is commonly known as quicksand. Or they died together in "a social supper gone horribly wrong."
The find will also help paleontologists learn more about Utahraptor anatomy. The team discovered bones from a 16-foot-long (4.8 meters) adult, four juveniles, and a baby that measured 3 feet (0.9 meters) long from snout to tail.
Much more at National Geographic, including a wild video showing how hard it was to get the chunk of sandstone off the cliff.