Which dinosaurs have horns

The spikes are much shorter than in S. A lot of other species which were assigned to Styracosaurus have since been assigned to other genera. Styracosaurus is in the Centrosaurinae, a subfamily of large North American horned dinosaurs marked by their "[prominent nose horns, lack of brow horns, a tall, deep face, and a projection in the rear of the nostril.

In , Peter Dodson found enough differences between Centrosaurus , Styracosaurus , and Monoclonius to call for separate genera, and that Styracosaurus looked more like Centrosaurus than either looked like Monoclonius.

The evolutionary origins of Styracosaurus were not known for years since fossils for early ceratopsians were sparse. When Protoceratops was found in , it shed light on early ceratopsid relationships, [16] but a few decades passed till more finds filled the gap. New findings in the late s and s, such as Zuniceratops , the first known ceratopsian with brow horns, and Yinlong , the first known Jurassic ceratopsian, show what the ancestors of Styracosaurus may have looked like.

These new findings have shed light on the origins of horned dinosaurs as a whole, and suggest that the group originated in the Jurassic in Asia, with true horned ceratopsians appearing by the start of the late Cretaceous in North America.

The large nasal horns and frills of Styracosaurus are one of the most distinct face adornments of all dinosaurs. Their role has been discussed since the first horned dinosaurs were found. Early in the 20th century, paleontologist R. Lull proposed that the frills of ceratopsians served to anchor their jaw muscles. Forster found no evidence of large muscle attachments on the frill bones. It was long thought that ceratopsians like Styracosaurus used their frills and horns in defense against the large meat-eating dinosaurs of the time.

While pitting, holes, lesions, and all kinds of harm on ceratopsid skulls are often attributed to horn damage in combat, a study found no evidence for horn thrust injuries that caused these forms of damage for example, there is no evidence of infection or healing. Instead, non-pathological bone resorption, or unknown bone diseases, are suggested as causes. The large frill on Styracosaurus and their relatives may have helped raise body area to regulate body temperature, [22] like the ears of the modern elephant.

A study also ruled out the theory that these frills evolved to help the dinosaurs recognize members of different ceratopsian species. Today, the prevailing theory is that frills may have helped these dinosaurs select their mates. In , one study found that as Triceratops matured, its head frill ballooned in size, suggesting that it became more important later in life —such as during the sexual selection process.

Fossil evidence has helped scientists decode other aspects of Triceratops behavior. While the frills may not have been intended as a defense mechanism, lesions found on Triceratop skulls reveal that these dinosaurs did sometimes fight one another. And unlike other ceratopsian species, Triceratops fossils are rarely found in groups, suggesting they lived solitary lives.

These herbivores also had beaklike mouths and powerful jaws lined with rows of sharp teeth to shred and grind low-lying vegetation. Evidence suggests that Triceratops teeth were incredibly complex, enabling them to slice through dense vegetation that would have been difficult for other herbivores to consume.

Scientists have long wondered about the evolutionary relationship between Triceratops horridus and its lesser-known relative, Triceratops prorsus. While they had much in common, Triceratops prorsus had a longer nasal horn, a shorter snout, and a more upright top horn.

Some paleontologists had theorized that the two species were descendents of an earlier dinosaur, in which case they would have lived at the same time. But in , a study of more than 50 Triceratops skulls from the Hell Creek Formation found that Triceratops horridus skulls appeared only in the lower layers of rock, while Triceratops prorsus was found only in the upper layers.

Skulls in the middle layers had features of both species. This finding suggests that Triceratops horridus evolved into the other species over one or two million years. No species of Triceratops lived much longer than that. But scientists have no real evidence the two Cretaceous beasts ever tangled. And a s Mary Halton at the BBC reports, a new study adds to the evidence that the often elaborate frills and horns of Triceratops and other ceratopsians , or horned dinosaurs, were all about looking good, not preparing them for dinosaur death matches.

Over the years, paleontologists have struggled to understand why horned dinos developed such elaborate horns and frills. And the number of these spike-faced creatures known to exist is climbing. In fact, the number of known horned dinosaurs that roamed Asia and North America has tripled over the last 20 years from just 23 identified in About feet long and tons. No horn on snout; medium-sized frill with two long horns on top. Although Diabloceratops has only recently been announced to the general public, this horned dinosaur has been familiar to paleontologists ever since , when its near-intact skull was discovered in southern Utah.

Eight years of analysis and preparation have yielded what may or may not be a ceratopsian "missing link": Diabloceratops seems to have evolved from the smaller horned dinosaurs of the early Cretaceous period, yet it predated more advanced genera like Centrosaurus and Triceratops by millions of years. As you might expect given its evolutionary position, the massive head of Diabloceratops was ornamented in a unique way: it lacked a horn on its snout, but had a medium-sized, Centrosaurus-like frill with two sharp horns jutting up from either side.

It's possible that Diabloceratops' frill was covered with a thin layer of skin that changed color during mating season. Diceratops was "diagnosed" way back in on the basis of a single, two-horned skull lacking the characteristic nasal horn of Triceratops; however, some paleontologists believe this specimen was actually a deformed individual of the latter dinosaur.

About 20 feet long and 2 tons. Long, curving horn on snout; two horns on frill. Einiosaurus was distinguished from its more famous cousins like Centrosaurus and Triceratops by the single, downward-curving horn jutting out from the middle of its snout.

The discovery of numerous bones jumbled together representing at least 15 separate individuals indicates that this dinosaur may have traveled in herds, at least one of which reached a catastrophic end—possibly when all the members drowned while trying to cross a flooding river. About 30 feet long and three tons. Large size; forward-curving horns. Even as some paleontologists argue that the roster of ceratopsians horned, frilled dinosaurs needs to be severely trimmed—on the theory that some of these dinosaurs were actually growth stages of existing dinosaurs—others have persisted in naming new genera.

A good example is Eotriceratops, which the average person would find virtually indistinguishable from Triceratops but which merits its own name thanks to some obscure anatomical features for example, the shape of its jugal horn, epoccipitals, and premaxilla. Interestingly, the "type specimen" of Eotriceratops bears bite marks above the left eye, perhaps remnants of an encounter with a hungry Tyrannosaurus Rex.

About three feet long and 50 pounds. Small size; small but thick skull. Most ceratopsians , or horned, frilled dinosaurs, are represented in the fossil record by truly massive skulls; for example, Triceratops had one of the biggest heads of any land animal that ever lived.

That's not the case for Gobiceratops, which was "diagnosed" in based on the single, tiny skull of a juvenile, less than two inches wide. Not much is known about how this small, herbivorous dinosaur lived, but it seems to have been related to another early ceratopsian of central Asia, Bagaceratops, and eventually gave rise to the giant ceratopsians of North America. Late Cretaceous 83 million years ago. Small size; tough, horny jaws. Gryphoceratops, which measured a bare two feet from head to tail, didn't boast any of the elaborate ornamentations of its larger, more famous cousins.

What Gryphoceratops did have in common with Triceratops and its ilk was its tough, horny beak, which it used to clip off equally tough vegetation. The smallest ceratopsian yet discovered in North America it was dug up very close to Canada's Dinosaur Provincial Park , Gryphoceratops was closely related to the equally "basal" Leptoceratops.

About five feet long and pounds. Small size; bipedal posture; beaked snout. Hongshanosaurus was very similar to Psittacosaurus without actually being a species of Psittacosaurus: this early Cretaceous ceratopsian horned, frilled dinosaur was distinguished from its more famous contemporary only by the distinctive shape of its skull.

Like Psittacosaurus, Hongshanosaurus didn't bear much of a resemblance to its descendants tens of millions of years down the line like Triceratops and Centrosaurus. In fact, it had many features in common with the small, two-legged ornithopods from which it evolved. Two brow horns; large frill with triangular serrations. Judiceratops was named in after the Judith River Formation in Montana where its "type fossil" was discovered.

Judiceratops' claim to fame is that it's the earliest "chasmosaurine" dinosaur yet identified, ancestral to the better-known Chasmosaurus that lived a few million years later—a kinship you can instantly detect in these two dinosaurs' distinctively ornamented frills.

Ceratopsians spanned the expanse of North America and Eurasia during the Cretaceous period, so the recent discovery of Koreaceratops in South Korea the first ceratopsian ever to be unearthed in this country should come as no surprise.

Dating from the middle Cretaceous, about million years ago, Koreaceratops was a relatively "basal" member of its breed, closely related to other early ceratopsians like Archaeoceratops and Cerasinops and not at all resembling ornate, later ceratopsians like Triceratops. What makes Koreaceratops especially interesting is its broad tail, which—while not an unusual feature in other early ceratopsians—has prompted some speculation about whether or not this dinosaur, and others like it, went for the occasional swim.

It's more likely that early ceratopsians would have evolved wide tails as either a sexually selected characteristic that is, males with bigger tails got to mate with more females or as a way to dissipate or collect heat, so the aquatic hypothesis will have to remain just that pending further evidence.

The head of the elephant-sized ceratopsian Kosmoceratops was decorated with 15 horns and horn-like structures, including a pair of large horns above the eyes vaguely resembling those of a bull. Plains of western North America. About six feet long and pounds. Slender build; small protuberances on face. Leptoceratops is an object lesson in how "primitive" dinosaurs sometimes lived directly alongside their more evolved cousins. This ceratopsian belonged to the same family as bigger, more florid dinosaurs like Triceratops and Styracosaurus , but its facial ornamentation was on the minimal side only a short frill and a curved lower jaw , and overall it was significantly smaller, only about six feet long and pounds.

In this respect, Leptoceratops was smaller even than the most common "small" ceratopsian of the late Cretaceous period, the pig-sized Protoceratops. How did Leptoceratops manage to be such a throwback to the distant progenitors of the ceratopsian family, tiny, dog-sized creatures like Psittacosaurus and Archaeoceratops that lived millions of years earlier?

Clearly, the ecosystem of late Cretaceous North America had room for at least one genus of small ceratopsian, which presumably stayed well out of the way of its smaller cousins and may even have done them a favor, by attracting the interest of hungry tyrannosaurs and raptors. Its low position on the food chain also explains another strange attribute of Leptoceratops, its ability to run away on its two hind legs when threatened!

Small size; small frill on head; possible bipedal posture. Voluminous evidence has come forward of early Cretaceous and even late Jurassic ceratopsian precursors, a notable example of which is Liaoceratops. Like other "basal" ceratopsians such as Chaoyangsaurus and Psittacosaurus , Liaoceratops was a pint-sized herbivore with a tiny, almost unnoticeable frill, and unlike later ceratopsians, it may have walked on its two hind legs.

Paleontologists are still sorting out the evolutionary relationships among these ancient dinosaurs; all we can say for certain is that the ceratopsians as a whole originated in Asia. Deserts of central Asia. Moderate size; large, sharp beak. Although it was described and named by the famous Chinese paleontologist Dong Zhiming, Magnirostris may or may not deserve its own genus. Most experts believe this dinosaur was actually a juvenile of a similar ceratopsian of late Cretaceous Mongolia, Bagaceratops, and it may even conceivably have been a species of Protoceratops.

However this dinosaur winds up being classified, the skull of Magnirostris is one of the best-preserved in the small ceratopsian fossil record, with a sharp, horny, roughly triangular beak that must have come in handy for shearing off tough vegetation. Large head with elaborate frill; two horns on forehead.

One of a group of ceratopsian dinosaurs announced in , Medusaceratops looked like a cross between a Triceratops and a Centrosaurus. It had two Triceratops-sized horns jutting out of the top of its head, but also a large, flat, vaguely butterfly-shaped frill reminiscent of the latter dinosaur.

The horns and frill were probably sexually selected characteristics, meaning males with bigger such accessories had the opportunity to mate with more females.

Alternatively, the horns may also have been used for intra-pack tussling and the frill as a means of communication if it was capable of changing colors. The "Medusa" part of this dinosaur's name, after the ancient Greek monster with snakes instead of hair, refers to the strange, bony, snake-like growths around Medusaceratops' frill. Plains of North America.

About 15 feet long and tons. Large frill with "wings" on bottom; two horns above eyes. What made Mercuriceratops stand out from the dozens of other ceratopsians of its habitat were the distinctive, wing-shaped protrusions on the bottom of its frill, which bear some resemblance to the helmet of the winged Greek god Mercury. Notably, almost identical specimens of this dinosaur were recently discovered on either side of the U.

The ancestral ceratopsian most people know as Microceratops received a name change in , to the slightly less snazzy Microceratus, because it turned out that "Microceratops" had already been assigned to a genus of insect.

Mojoceratops Greek for "mojo horned face" ; pronounced moe-joe-SEH-rah-tops. Large, heart-shaped frill on back of head. Fossil hunter Nicholas Longrich certainly had his mojo on when he diagnosed this new ceratopsian dinosaur based on a skull he found in storage at the American Museum of Natural History in New York along with other partial skulls residing in Canadian museums.

Mojoceratops' claim to fame is that its frill was even more elaborate than that of its closest relative, Centrosaurus : a tall, wide, bone-supported sail of skin that probably changed color with the seasons.

To judge by its underlying skeletal structure, Mojoceratops' frill was probably heart-shaped, which was fitting in that males used their frills to broadcast sexual availability or desire to the females of the herd.

Today, many paleontologists believe that the identified fossil specimens of Monoclonius should be assigned to Centrosaurus, which had a strikingly similar head equipped with one big horn on the end of its snout.

About 10 feet long and pounds. Small size; short frill and beak. The famous paleontologist Barnum Brown didn't know quite what to make of Montanoceratops when he unearthed its remains in Montana in ; it took him almost 20 years for him to get around to describing the type fossil, which he assigned to another basal ceratopsian, Leptoceratops.

A few years later, another naturalist, Charles M. Sternberg, reexamined the bones and erected the new genus Montanoceratops. The important thing about Montanoceratops is that it was a relatively small, "primitive" ceratopsian that shared its habitat with more advanced forms like Centrosaurus and Styracosaurus.

Clearly, these differently sized dinosaurs occupied different ecological niches, and did not directly compete with one another for food and other resources. Large nose; forward-facing brow horns. Nasutoceratops, first identified in , was distinguished from others of its kind by its unusually large nose and the remarkably steer-like pair of horns jutting out from over its eyes. On the other hand, the frill of Nasutoceratops was nothing special, lacking the elaborate notches, ridges, fringes, and decorations of other ceratopsians.