Everything about Triceratops totally explained
Triceratops is an extinct
genus of
herbivorous ceratopsid dinosaur that lived during the
late Maastrichtian stage of the Late
Cretaceous Period, around 68 to 65
million years ago (mya) in what is now
North America. It was one of the last dinosaur genera to appear before the great
Cretaceous–Tertiary extinction event. Bearing a large bony
frill and three
horns on its large four-legged body, and conjuring similarities with the modern
rhinoceros,
Triceratops is one of the most recognizable of all dinosaurs. The name
Triceratops, which literally means "three-horned face", is derived from the
Greek tri/τρι- meaning "three",
ceras/κέρας meaning "horn", and
-ops/ωψ meaning "face". Though it shared the landscape with and was
preyed upon by the fearsome
Tyrannosaurus, it's unclear whether the two battled the way they're commonly depicted in movies and children's dinosaur books and many cartoons.
Although no complete skeleton has been found,
Triceratops is well-known from numerous partial specimens collected since the introduction of the genus in 1887. The function of their frills and three distinctive facial horns has long inspired debate. Although traditionally viewed as defensive weapons against predators, the latest theories claim that it's more probable that these features were used in
courtship and dominance displays, much like the
antlers and horns of modern
reindeer,
mountain goats, or
rhinoceros beetles.
Triceratops is the best-known of the ceratopsids, though the genus's exact placement within the group has been a point of contention amongst
paleontologists. Two
species,
T. horridus and
T. prorsus, are considered valid, although many other species have been named.
Description
Individual
Triceratops are estimated to have reached about 7.9 to 9.0
m (26.0–29.5
ft) in length, 2.9 to 3.0 m (9.5–9.8 ft) in height, and 6.1–12.0
tonnes (13,000-26,000
lb) in
weight. The most distinctive feature is their large
skull, among the largest of all land animals. It could grow to be over 2 m (7 ft) in length, This conclusion doesn't preclude a sprawling gait for confrontations or feeding.
Classification
Triceratops is the best known genus of the
Ceratopsidae, a family of large North American
horned dinosaurs. The exact location of
Triceratops among the ceratopsians has been debated over the years. Confusion stemmed mainly from the combination of short, solid frills (similar to that of
Centrosaurinae), and the long brow horns (more akin to
Ceratopsinae, also known as Chasmosaurinae). In the first overview of horned dinosaurs,
R. S. Lull hypothesized two lineages, one of
Monoclonius and
Centrosaurus leading to
Triceratops, the other with
Ceratops and
Torosaurus, making
Triceratops a centrosaurine as the group is understood today. Later revisions supported this view, formally describing the first, short-frilled group as Centrosaurinae (including
Triceratops), and the second, long-frilled group as Chasmosaurinae.
In 1949,
C. M. Sternberg was the first to question this and favoured instead that
Triceratops was more closely related to
Arrhinoceratops and
Chasmosaurus based on skull and horn features, making
Triceratops a ceratopsine (chasmosaurine of his usage) genus. However, he was largely ignored with
John Ostrom, and later David Norman, both placing
Triceratops within Centrosaurinae.
Subsequent discoveries and analyses upheld Sternberg's view on the position of
Triceratops, with Lehman defining both subfamilies in 1990 and diagnosing Triceratops as ceratopsine (chasmosaurine of his usage) on the basis of several morphological features. In fact, it fits well into the ceratopsine subfamily, apart from its one feature of a shortened frill. Further research by Peter Dodson, including a 1990 cladistic analysis and a 1993 study using RFTRA (resistant-fit theta-rho analysis), a morphometric technique which systematically measures similarities in skull shape, reinforces Triceratops' placement in the ceratopsine subfamily.
Use in phylogenetics
In
phylogenetic taxonomy, the genus has been used as a reference point in the definition of Dinosauria; Dinosaurs have been designated as all descendants of the most recent common ancestor of
Triceratops and
Neornithes (for example modern
birds). Furthermore, the bird-hipped dinosaurs,
Ornithischia, have been designated as all dinosaurs with a more recent common ancestor to
Triceratops than modern birds.
Origins
For many years the origins of
Triceratops have been largely obscure. In 1922, the newly discovered
Protoceratops was seen as its ancestor by
Henry Fairfield Osborn, but many decades passed before additional findings came to light. However, recent years have been fruitful for the discovery of several dinosaurs related to ancestors of
Triceratops.
Zuniceratops, the earliest known ceratopsian with brow horns, was described in the late 1990s, and
Yinlong, the first known
Jurassic ceratopsian, in 2005.
These new finds have been vital in illustrating the origins of horned dinosaurs in general, suggesting an
Asian origin in the Jurassic, and the appearance of truly horned ceratopsians by the beginning of the late Cretaceous in North America. As
Triceratops is increasingly shown to be a member of the long-frilled Ceratopsinae subfamily, a likely ancestor may have resembled
Chasmosaurus, which thrived some 5 million years earlier.
Discoveries and species
The first named specimen now attributed to
Triceratops is a pair of brow horns attached to a skull roof, found near
Denver, Colorado in the spring of 1887. This specimen was sent to
Othniel Charles Marsh, who believed that the
formation from which it came dated from the
Pliocene, and that the bones belonged to a particularly large and unusual
bison, which he named
Bison alticornis. but he still believed
B. alticornis to be a Pliocene
mammal. It took a third and much more complete skull to change his mind. The specimen, collected in 1888 by
John Bell Hatcher from the
Lance Formation of
Wyoming, was initially described as another species of
Ceratops. After reflection, however, Marsh changed his mind and gave it the generic name
Triceratops, accepting his
Bison alticornis as another species of
Ceratops (it would later be added to
Triceratops Part of their rationale was that generally there are only one or two species of any large animal in a region (modern examples being the
elephant and the
giraffe in modern Africa). To their findings, Lehman added the old Lull-Sternberg lineages combined with maturity and
sexual dimorphism, suggesting that the
T. horridus-
T. prorsus-
T. brevicornus lineage was composed of females, the
T.calicornis-
T.elatus lineage was made up of males, and the
T. obtusus-
T. hatcheri lineage was of
pathologic old males. She found that
T. horridus and several other species belonged together, and
T. prorsus and
T. brevicornus stood alone, and since there were many more specimens in the first group, she suggested that this meant the two groups were two species. It is still possible to interpret this reasoning as describing a single species with sexual dimorphism.
Valid species
T. horridus (Marsh, 1889) (originally Ceratops) (type species)
T. prorsus (Marsh, 1890)
Doubtful species
The following species are considered nomina dubia ("dubious names"), and are based on remains that are too poor or incomplete to be distinguished from pre-existing Triceratops species.
T. albertensis (C. M. Sternberg, 1949)
T. alticornis (Marsh, 1887 (originally Bison))
T. eurycephalus (Schlaikjer, 1935)
T. galeus (Marsh, 1889)
T. ingens (Lull, 1915)
T. maximus (Brown, 1933)
T. sulcatus (Marsh, 1890)
Misassignments
T. brevicornus (Hatcher, 1905) (=T. prorsus)
T. calicornus (Marsh, 1898) (=T. horridus)
T. elatus (Marsh, 1891) (=T. horridus)
T. flabellatus (Marsh, 1889) (=T. horridus)
T. hatcheri (Lull, 1907) (=Diceratus hatcheri)
T. mortuarius (Cope, 1874) (nomen dubium; originally Polyonax; =Polyonax mortuarius)
T. obtusus (Marsh, 1898) (=T. horridus)
T. serratus (Marsh, 1890) (=T. horridus)
T. sylvestris (Cope, 1872) (nomen dubium; originally Agathaumas sylvestris)
Paleobiology
Although Triceratops are commonly portrayed as herding animals, there's currently no solid evidence that they lived in herds. Unlike other horned dinosaurs, some of which are known from sites preserving dozens or hundreds of individuals, all Triceratops finds known at present preserve only solitary individuals. Similarly, Barnum Brown claimed to have seen over 500 skulls in the field. Because Triceratops teeth, horn fragments, frill fragments, and other skull fragments are such abundant fossils in the Lancian faunal stage of the late Maastrichtian (late Cretaceous, 68 to 65 mya) Period of western North America, it's regarded as among the dominant herbivores of the time, if not the most dominant herbivore. In 1986, Robert Bakker estimated it as making up 5/6ths of the large dinosaur fauna at the end of the Cretaceous. Unlike most animals, skull fossils are far more common than postcranial bones for Triceratops, suggesting that the skull had an unusually high preservation potential.
Triceratops was one of the last ceratopsian genera to appear before the Cretaceous-Tertiary extinction event. The related Diceratus and Torosaurus, and the more distantly related diminutive Leptoceratops, were also present, though their remains have been rarely encountered.
Triceratops teeth were arranged in groups called batteries, of 36 to 40 tooth columns, in each side of each jaw with 3 to 5 stacked teeth per column, depending on the size of the animal. and others suggesting ferns, which then grew in prairies.
Functions of the horns and frill
There has been much speculation over the functions of Triceratops' head adornments. The two main theories have revolved around use in combat, or display in courtship, with the latter thought now to be the most likely primary function. This has been put forward by other authors over the years, but later studies don't find evidence of large muscle attachments on the frill bones.
Triceratops were long thought to have possibly used their horns and frills in combat with predators such as Tyrannosaurus, the idea being discussed first by C. H. Sternberg in 1917 and 70 years later by Robert Bakker. There is evidence that Tyrannosaurus did prey upon them, as a Triceratops pelvis has been found with tyrannosaur toothmarks and subsequent healing, indicating the wound was made while the animal was alive.
In 2005, a BBC documentary, The Truth About Killer Dinosaurs, tested how Triceratops might have defended themselves against large predators like Tyrannosaurus. To see if Triceratops could have charged other dinosaurs, as would a modern-day rhinoceros, an artificial Triceratops skull was made and propelled into simulated Tyrannosaurus skin at 24 km/h (15 mph). The brow horns penetrated the skin, but the blunt nose horn and the beak could not, and the front of the skull broke. The conclusion drawn was that it would have been impossible for Triceratops to have defended themselves in this way—instead they probably stood their ground when attacked by large predators, using their horns for goring if the predator came close enough.
In addition to combat with predators using horns, Triceratops are classically shown engaging each other in combat with horns locked. While studies show that such activity would be feasible, if unlike that of present-day horned animals, there's no evidence that they actually did so. Additionally, although pitting, holes, lesions, and other damage on Triceratops skulls (and the skulls of other ceratopsids) are often attributed to horn damage in combat, a recent study finds no evidence for horn thrust injuries causing these forms of damage (for example, there's no evidence of infection or healing). Instead, non-pathological bone resorption, or unknown bone diseases, are suggested as causes.
The large frill also may have helped to increase body area to regulate body temperature. A similar theory has been proposed regarding the plates of Stegosaurus, although this use alone wouldn't account for the bizarre and extravagant variation seen in different members of the Ceratopsidae. A recent study of the smallest Triceratops skull, ascertained to be a juvenile, shows the frill and horns developed at a very early age, predating sexual development and thus probably important for visual communication and species recognition in general. The large eyes and shortened features, a hallmark of "cute" baby mammals, also suggest that the parent Triceratops may have cared for its young.
Depiction in recent popular media
The distinctive appearance of Triceratops has led to them being frequently depicted in films, computer games and documentaries. They appear in the film Jurassic Park, where one is portrayed as sick and is being treated by humans. They have also been featured in three major dinosaur documentaries: Walking with Dinosaurs, The Truth About Killer Dinosaurs and Prehistoric Park.
They are famously known as "three-horns" (and are so named in The Land Before Time animated film and its numerous sequels) due to the three prominent horns on their head and nose, which have become almost synonymous with the dinosaurs. The shorthand "Trike" is another common informal name, and is also the name of the Triceratops character in the children's book series and television cartoon series Harry and His Bucket Full of Dinosaurs. Other TV series include Slag of fame, Dinosaucers, Dino-Riders and Dinozaurs. In the first series of Mighty Morphin' Power Rangers, the blue ranger's robot, called a "zord", took the shape of a triceratops, and the ranger's helmet was fashioned after the animal.
A recurring theme, especially in children's dinosaur books, is a climactic showdown or battle between Triceratops and T. rex. As such these two dinosaurs are often depicted and thought of as natural enemies. A memorable but anachronistic battle with Ceratosaurus substituting for T. rex is featured in the 1966 movie One Million Years B.C.
Triceratops appears in video games either derived directly from the Jurassic Park series or similarly themed, namely the 1997 PC games and, and the 2000 PC and Playstation game Dino Crisis 2. Triceratops also features in the Zoo Tycoon franchise. As well, it's a popular creature used in games designed by Nintendo, including Diddy Kong Racing and Starfox Adventures. Triceratops (the species are not identified) is also the official state fossil of South Dakota, and the official state dinosaur of Wyoming.
Further Information
Get more info on 'Triceratops'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://triceratops.totallyexplained.com">Triceratops Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |
