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Travel A road trip in Burgundy reveals far more than fine wine. Travel My Hometown In L. Subscriber Exclusive Content. Why are people so dang obsessed with Mars? How viruses shape our world. The era of greyhound racing in the U. See how people have imagined life on Mars through history. See More. United States Change. One of the earliest identified ceratopsians was the late Jurassic Chaoyangsaurus , which weighed 30 pounds and had only the most rudimentary hint of a horn and frill.
Other early members of the horned, frilled dinosaur family may have been even smaller. Why did Triceratops have such a prominent frill?
As with all such anatomical structures in the animal kingdom, this thin flap of skin over solid bone likely served a dual or even triple purpose. The most probable explanation is that it was used to signal other members of the herd.
A brightly colored frill, flushed pink by the numerous blood vessels under its surface, may have signaled sexual availability or warned of the approach of a hungry Tyrannosaurus rex. It may also have had some temperature-regulation function, assuming that Triceratops were cold-blooded.
In modern times, many dinosaur genera have been reinterpreted as "growth stages" of previously named genera. This appears to be true with the two-horned Torosaurus , which some paleontologists argue represents the remains of unusually long-lived Triceratops males whose frills continued to grow into old age.
But it's doubtful that Triceratops genus name will have to change to Torosaurus , the way Brontosaurus became Apatosaurus. In , American paleontologist Othniel C. Marsh examined a partial Triceratops skull, complete with horns , discovered in the American West and incorrectly assigned the remains to the grazing mammal Bison alticornis , which didn't evolve until tens of millions of years later, long after dinosaurs were extinct.
Marsh quickly reversed this embarrassing blunder, though more were made on both sides in the so-called Bone Wars between Marsh and rival paleontologist Edward Drinker Cope.
Because the skull and horns of triceratops were so large, so distinctive, and so resistant to natural erosion—and because so many specimens were discovered in the American West—museums and individual collectors tend to dig deep to enrich their collections. Unfortunately, the hunger for Triceratops bones has resulted in a thriving gray market, as unscrupulous fossil hunters tried to poach and sell this dinosaur's remains.
Triceratops fossils date to the very end of the Cretaceous period, just before the K-T asteroid impact killed the dinosaurs. By then, paleontologists believe, the pace of dinosaur evolution had slowed to a crawl and the resulting loss of diversity, combined with other factors, virtually guaranteed their quick extinction. Along with its fellow plant eaters, Triceratops was doomed by the loss of its accustomed vegetation, as clouds of dust circled the globe in the wake of the K-T catastrophe and blotted out the sun.
Actively scan device characteristics for identification. Use precise geolocation data. Select personalised content. In a study in the Journal of Vertebrate Paleontology , Scannella and his colleague John "Jack" Horner argued that Torosaurus , which is mainly distinguished from Triceratops by having an expanded frill with large holes, was actually Triceratops in old age.
In a subsequent study in the journal PLOS ONE , Scannella and Horner used similar reasoning to argue Nedoceratops hatcheri , of which there is only a single specimen, is actually a transitional stage between the young Triceratops and the old Torosaurus.
Again, one of the main differences between the animals in question is the frill: Torosaurus has large frill holes, which are smaller in Nedoceratops and absent in Triceratops though some specimens appear to show evidence of the beginning of holes. This suggests that the holes grow over time as the frill develops and expands, they reasoned.
However, some other paleontologists contest this single-genus idea. In a PLOS ONE article, for instance, researchers presented evidence of Torosaurus bones that are not fully fused , suggesting the specimen is still immature and, therefore, not a fully mature Triceratops.
They further suggested the frill holes of Nedoceratops are pathological related to a disease or health issue. More fossils of Nedoceratops and a distinctly juvenile specimen of Torosaurus would settle the debate, Scannella said.
Triceratops was a massive animal, comparable in size to an African elephant , according to a article in the journal Cretaceous Research. It grew up to 30 feet 9 meters and weighed well over 11, lbs.
It had strong limbs to move and support its massive body. The forelimbs, which were shorter than the rear ones, each had three hooves; the rear limbs had four hooves each. A study in the journal Proceedings of the Royal Society B suggested that Triceratops had an upright posture like an elephant's, rather than a sprawling, elbows-out posture like a lizard's.
The head of Triceratops was among the largest of all land animals, some making up one-third of the entire length of the dinosaur's body.
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