Triceratops
Scientific Classification
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Order: Ornithischia
Suborder: Ceratopsia
Family: Ceratopsidae
Subfamily: Chasmosaurinae
Tribe: Triceratopsini
Genus: Triceratops meaning "Three-horned Face"
Described by Othniel Charles, Marsh 1889
Type Species: Triceratops horridus
Species:
-Triceratops horridus meaning "Rough Three-horned Face" (Type Species), Marsh 1889
-Triceratops prorsus meaning "Forward Three-horned Face", Marsh 1890
Synonyms:
-Agathaumas? Cope, 1872
-Polyonax? Cope, 1874
-Bison alticornis Marsh, 1887
-Sterrholophus Marsh, 1891
-Claorhynchus? Cope, 1892
-Ugrosaurus Cobabe & Fastovsky, 1987
-Eotriceratops? Wu et al., 2007
-Nedoceratops? Ukrainsky, 2007
-Ojoceratops? Sullivan & Lucas, 2010
-Tatankaceratops? Ott & Larson, 2010
Present Park Population: Triceratops horridus (20; 11 adults, 9 youngsters; 13 male, 14 female)
Park Diet: Ferns, elephant feed, cow feed, low shrubs, cycads, banana leaves, watermelons, and pumpkins.
Natural Diet: Ferns, low shrubs, and cycads.
Lifespan: 32 Years.
Habitat: Open areas like floodplain swamps, fern prairies, and open-canopy forests with large amounts of food.
Native Ecosystem: Western North America, on what was then an island continent known as Laramidia. Hell Creek Formation, Lance Formation, Evanston Formation, Scollard Formation, Laramie Formation, Denver Formation, Southwestern Alberta and Saskatchewan, Canada, Montana, South Dakota, Wyoming, Colorado, and possibly New Mexico and Texas, USA, 68-66 Million Years Ago, Maastrichtian Stage.
Breeding Season: June and July.
Gestation Period: Three months.
Eggs Laid: Seven to eighteen.
Hatching Time: Three to five weeks, depending on atmospheric moisture.
Danger Level: Extremely dangerous proceed with extreme caution, 8 out of 10.
Park Five Star Rating: 5 Stars.
Summary: Triceratops horridus is the Cretaceous equivalent of Asian Water Buffalo: tough, sturdy, and short-tempered. Although they are normally peaceful, they will attack viciously once provoked. Triceratops is one of the most famous ceratopsians and one of the most recognizable non-avian dinosaurs, sporting a recognizable three-horned face and bony frill. These animals inhabit stretches of open prairies or marshlands in small herds, where they feed on ferns and woody shrubs. Triceratops are extremely tenacious and aggressive in temperament. Specimens have been observed surviving with their horns, tails, and even snouts that are partially bitten off. This gives these very old animals, with their denuded brow horns and various scars, a hardened, battle-worn character. Even adult T. rex must take caution of these brutes
Discovery and Identification: The first named fossil specimen now attributed to Triceratops is a pair of brow horns attached to a skull roof that was found by George Lyman Cannon near Denver, Colorado, in the spring of 1887. This specimen was sent to Othneil 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. He realized that there were horned dinosaurs by the next year, which saw his publication of the genus Ceratops from fragmentary remains, but he still believed B. alticornis to be a Pliocene mammal. It took a third and much more complete skull to fully change his mind.
Although not confidentially assignable, fossils possibly belonging to Triceratops were described as two taxa, Agathaumas sylvestris, and Polyonax mortuarius, in 1872 and 1874, respectively, by Marsh's archrival Edward Drinker Cope. Agathaumas was named based on a pelvis, several vertebrae, and a few ribs collected by Fielding Bradford Meek and Henry Martyn Bannister near the Green River of southeastern Wyoming from layers coming from the Maastrichtian Lance Formation. Due to the fragmentary nature of the remains, they can only confidently be assigned to Ceratopsidae. Polyonax mortuarius was collected by Cope himself in 1873 from northeastern Colorado, possibly coming from the Maastrichtian Denver Formation. The fossils only consisted of fragmentary horn cores, 3 dorsal vertebrae, and fragmentary limb elements. Polyonax has the same issue as Agathaumas, with the fragmentary remains non-assignable beyond Ceratopsidae.
The Triceratops holotype, YPM 1820, was collected in 1888 from the Lance Formation of Wyoming by fossil hunter John Bell Hatcher, but Marsh initially described this specimen as another species of Ceratops. Cowboy Edmund B. Wilson had been startled by the sight of a monstrous skull poking out of the side of a ravine. He tried to recover it by throwing a lasso around one of the horns. When it broke off, the skull tumbling to the bottom of the cleft, Wilson brought the horn to his boss. His boss was a rancher and avid fossil collector Charles Arthur Guernsey, who just so happened to show it to Hatcher. Marsh subsequently ordered Hatcher to locate and salvage the skull. The holotype was first named Ceratops horridus. When further preparation uncovered the third nose horn, Marsh changed his mind and gave the piece the new generic name Triceratops (lit. 'three horn face'), accepting his Bison alticornis as another species of Ceratops. It would, however, later be added to Triceratops. The sturdy nature of the animal's skull has ensured that many examples have been preserved as fossils, allowing variations between species and individuals to be studied. Triceratops remains have subsequently been found in Montana and South Dakota (and more in Colorado and Wyoming), as well as the Canadian provinces of Saskatchewan and Alberta.
Species: After Triceratops was described, between 1889 and 1891, Hatcher collected another thirty-one of its skulls with great effort. The first species had been named T. horridus by Marsh. Its specific name was derived from the Latin word horridus meaning "rough" or "rugose", perhaps referring to the type specimen's rough texture, later identified as an aged individual. The additional skulls varied to a lesser or greater degree from the original holotype. This variation is unsurprising, given that Triceratops' skulls are large three-dimensional objects from individuals of different ages and both sexes that were subjected to different amounts and directions of pressure during fossilization.
In the first attempt to understand the many species, Richard Swann Lull found two groups, although he did not say how he distinguished them. One group is composed of T. horridus, T. prorsus, and T. brevicornus ('the short-horned'). The other is composed of T. elatus and T. calicornis. Two species (T. serratus and T. flabellatus) stood apart from these groups. By 1933, alongside his revision of the landmark 1907 Hatcher–Marsh–Lull monograph of all known ceratopsians, he retained his two groups and two unaffiliated species, with a third lineage of T. obtusus and T. hatcheri ('Hatcher's') that was characterized by a very small nasal horn. T. horridus–T. prorsus–T. brevicornus was now thought to be the most conservative lineage, with an increase in skull size and a decrease in nasal horn size. T. elatus–T. calicornis was defined by having large brow horns and small nasal horns. Charles Mortram Sternberg made one modification by adding T. eurycephalus ('the wide-headed') and suggesting that it linked the second and third lineages closer together than they were to the T. horridus lineage.
With time, the idea that the differing skulls might be representative of individual variation within one (or two) species gained popularity. In 1986, John Ostrom and Peter Wellnhofer published a paper in which they proposed that there was only one species, Triceratops horridus. Part of their rationale was that there are generally only one or two species of any large animal in a region. To their findings, Thomas 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.
These findings were contested a few years later by paleontologist Catherine Forster, who reanalyzed Triceratops material more comprehensively and concluded that the remains fell into two species, T. horridus, and T. prorsus, although the distinctive skull of T. ("Nedoceratops") hatcheri differed enough to warrant a separate genus. She found that T. horridus and several other species belonged together and that T. prorsus and T. brevicornus stood alone. 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 the differences as representing a single species with sexual dimorphism.
In 2009, John Scannella and Denver Fowler supported the separation of T. prorsus and T. horridus, noting that the two species are also separated stratigraphically within the Hell Creek Formation, indicating that they did not live together at the same time.
Valid species:
-Triceratops horridus (Marsh, 1889) Marsh, 1889 (originally Ceratops) (type species).
-Triceratops prorsus (Marsh, 1890).
Synonyms and doubtful species: Some of the following species are synonyms, as indicated in parentheses ("=T. horridus" or "=T. prorsus"). All the others are each considered a nomen dubium (lit. 'Dubious name') because they are based on remains too poor or incomplete to be distinguished from pre-existing Triceratops species.
-T. albertensis C. M. Sternberg, 1949
-T. alticornis (Marsh 1887) Hatcher, Marsh, and Lull, 1907 [originally Bison alticornis, Marsh 1887, and Ceratops alticornis, Marsh 1888]
-T. brevicornus Hatcher, 1905 (=T. prorsus)
-T. calicornis Marsh, 1898 (=T. horridus)
-T. elatus Marsh, 1891 (=T. horridus)
-T. eurycephalus Schlaikjer, 1935
-T. flabellatus Marsh, 1889 (= Sterrholophus Marsh, 1891) (=T. horridus)
-T. galeus Marsh, 1889
-T. hatcheri (Hatcher & Lull 1905) Lull, 1933 (contentious)
-T. ingens Marsh vide Lull, 1915
-T. maximus Brown, 1933
-T. mortuarius (Cope, 1874) Kuhn, 1936 (nomen dubium; originally Polyonax mortuarius)
-T. obtusus Marsh, 1898 (=T. horridus)
-T. serratus Marsh, 1890 (=T. horridus)
-T. sulcatus Marsh, 1890
-T. sylvestris (Cope, 1872) Kuhn, 1936 (nomen dubium; originally Agathaumas sylvestris)
Description: Triceratops horridus was much larger than Triceratops prorsus, they have upward horns, shallower snout, and a short nasal boss horn protruding outwards. Triceratops prorsus horns swoop downwards instead as well as having a longer nasal boss that slants forward. They can also be told apart based on their color scheme skins, especially their faces and frills, Adults show individual variation in terms of head ornamentation. They are covered in large, polygonal scales and feature scales, along with a forelimb gait locomotion, unlike that of large, quadrupedal mammals.
Triceratops horridus
Adults have backs that are dark brown grading down to a brown colored with black stripes and spots, nasal sacs, black feet, faces, and black-tipped horns and tails, they have a pair of three-foot-long pale brow horns, small nasal horns, black bristle filament quilled back, hindquarters, which are short, and base of their tails which are long, they are mostly scaly with osteoderm bumps, and a pale scaly ventral belly similar to crocodiles and a frill with a pair of circular spots rows of visible pale osteoderms.
Males have gold-yellow stripes running down their backs mixing with the black stripes, they have a blue face, with a black stripe running down to the top beak through the eyes to back to the base of the frill on each side, reddish-orange eye rings, yellow nasal sacs, the frill is yellow-orange with black stripes, and the reddish-orange circular spots with black spots in the center. They have thicker horns that tend to curve downwards than forwards, usually closer together, almost parallel to each other.
Older individuals have bronze nasal sacs, longer horns with scars and broken and worn down horns, a darker blue face, dark red eye rings, frill spots, and bright orange frills covered with scars and sometimes notch bitemarks.
Females are identical to the males except they have a gray face, light brown circular frill spots with no spots in the center, and vivid yellow-orange frills, those individuals are either solitary or dominant bulls of the herd. Their horns are thin that curve upwards and fork out, forming a wide, V-shaped gap between them.
Adolescents are identical to the adult female but are covered with light brown scales. Their horns grow further and have longer snouts.
Juveniles are identical to adolescents but have curved upwards horns and short horns, a pale frill, grayish brown faces, and they have brown spots, stripes, feet, and tail tips.
Hatchlings identical to the juveniles have shorter horns, they are tannish brown with light brown spots, stripes, feet, and tail tip, and covered with long bristles over their bodies and tails.
The horns of juveniles and hatchlings have shortened faces and horns that turned upward in an almost-vertical orientation
Size: Triceratops was a very large animal, reaching 8–9 meters (26–30 ft) in length and weighing 5–9 metric tons (5.5–9.9 short tons). A specimen of T. horridus named Kelsey measured 6.7–7.3 meters (22–24 ft) long, has a 2-meter (6.5 ft) skull, stood about 2.3 meters (7.5 ft) tall, and was estimated by the Black Hills Institute to weigh approximately 5.4 metric tons (6.0 short tons).
Skull: Like all chasmosaurines, Triceratops had a large skull relative to its body size, among the largest of all land animals. The largest-known skull, specimen MWC 7584 (formerly BYU 12183), is estimated to have been 2.5 meters (8.2 ft) in length when complete and could reach almost a third of the length of the entire animal.
The front of the head was equipped with a large beak in front of its teeth. The core of the top beak was formed by a special rostral bone. Behind it, the premaxillary bones were located, embayed from behind by very large, circular nostrils. In chasmosaurines, the premaxilla met on their midline in a complex bone plate, the rear edge of which was reinforced by the "narial strut". From the base of this strut, a triangular process jutted out into the nostril. Triceratops differs from most relatives in that this process was hollowed out on the outer side. Behind the toothless premaxilla, the maxilla bore thirty-six to forty tooth positions, in which three to five teeth per position were vertically stacked. The teeth were closely appressed, forming a "dental battery" curving to the inside. The skull bore a single horn on the snout above the nostrils. In Triceratops, the nose horn is sometimes recognized as a separate ossification, the epinasal.
The skull also featured a pair of supraorbital "brow" horns approximately 1 meter (3.3 ft) long, with one above each eye. The jugal bones pointed downward at the rear sides of the skull and were capped by separate epijugals. With Triceratops, these were not particularly large and sometimes touched the quadratojugals. The bones of the skull roof were fused and by a folding of the frontal bones, a "double" skull roof was created. In Triceratops, some specimens show a fontanelle, an opening in the upper roof layer. The cavity between the layers invaded the bone cores of the brow horns.
The lengths of the horns vary, likely due to age, some sport asymmetrical horn lengths or bear some battle damages, like horn tips chipped or even snapped off.
At the rear of the skull, the outer squamosal bones and the inner parietal bones grew into a relatively short, bony frill, adorned with epoccipitals in young specimens. These were low triangular processes on the frill edge, representing separate skin ossifications or osteoderms. Typically, with Triceratops specimens, there are two epoccipitals present on each parietal bone, with an additional central process on their border. Each squamosal bone had five processes. Most other ceratopsids had large parietal fenestrae, and openings in their frills, but those of Triceratops were noticeably solid unless the genus Torosaurus represents mature Triceratops individuals, which it most likely does not. Under the frill, at the rear of the skull, a huge occipital condyle, up to 106 millimeters (4.2 in) in diameter, connected the head to the neck.
Older individuals may have frills covered with scars and bite marks even possibly during encounters with T. Rex.
The lower jaws were elongated and met at their tips in a shared epidentary bone, the core of the toothless lower beak. In the dentary bone, the tooth battery curved to the outside to meet the battery of the upper jaw. At the rear of the lower jaw, the articular bone was exceptionally wide, matching the general width of the jaw joint. T. horridus can be distinguished from T. prorsus by having a shallower snout.
Postcranial skeleton: Chasmosaurines showed little variation in their postcranial skeleton. The skeleton of Triceratops is markedly robust. Both Triceratops species possessed a very sturdy build, with strong limbs, short hands with three hooves each, and short feet with four hooves each. The vertebral column consisted of ten neck, twelve back, ten sacral, and about forty-five tail vertebrae. The front neck vertebrae were fused into a syncervical. Traditionally, this was assumed to have incorporated the first three vertebrae, thus implying that the frontmost atlas was very large and sported a neural spine. Later interpretations revived an old hypothesis by John Bell Hatcher that, at the very front, a vestige of the real atlas can be observed, the syncervical then consisting of four vertebrae. The vertebral count mentioned is adjusted to this view. In Triceratops, the neural spines of the neck are constant in height and don't gradually slope upwards. Another peculiarity is that the neck ribs only begin to lengthen with the ninth cervical vertebra.
The rather short and high vertebrae of the back were, in its middle region, reinforced by ossified tendons running along the tops of the neural arches. The straight sacrum was long and adult individuals show a fusion of all sacral vertebrae. In Triceratops the first four and last two sacrals had transverse processes, connecting the vertebral column to the pelvis, that were fused at their distal ends. Sacrals seven and eight had longer processes, causing the sacrum to have an oval profile in the top view. On top of the sacrum, a neural plate was present formed by a fusion of the neural spines of the second through fifth vertebrae. Triceratops had a large pelvis with a long ilium. The ischium was curved downwards. The foot was short with four functional toes. The phalangeal formula of the foot is 2-3-4-5-0.
Although certainly quadrupedal, the posture of horned dinosaurs has long been the subject of some debate. Originally, it was believed that the front legs of the animal had to be sprawled at a considerable angle from the thorax to better bear the weight of the head. This stance can be seen in paintings by Charles Knight and Rudolph Zallinger. Ichnological evidence in the form of trackways from horned dinosaurs and recent reconstructions of skeletons (both physical and digital) seem to show that Triceratops and other ceratopsids maintained an upright stance during normal locomotion, with the elbows flexed to behind and slightly bowed out, in an intermediate state between fully upright and fully sprawling, comparable to the modern rhinoceros.
The hands and forearms of Triceratops retained a fairly primitive structure when compared to other quadrupedal dinosaurs, such as thyreophorans and many sauropods. In those two groups, the forelimbs of quadrupedal species were usually rotated so that the hands faced forward with palms backward ("pronated") as the animals walked. Triceratops, like other ceratopsians and related quadrupedal ornithopods (together forming the Cerapoda), walked with most of their fingers pointing out and away from the body, the original condition for dinosaurs. This was also retained by bipedal forms, like theropods. In Triceratops, the weight of the body was carried by only the first three fingers of the hand, while digits 4 and 5 were vestigial and lacked claws or hooves. The phalangeal formula of the hand is 2-3-4-3-1, meaning that the first or innermost finger of the forelimb has two bones, the next has three, the next has four, etc.
Skin: Preserved skin from Triceratops is known. This skin consists of large scales, some of which exceed 100 millimeters (3.9 in) across, which have conical projections rising from their center. A preserved piece of skin from the frill of a specimen is also known, which consists of small polygonal basement scales.
Classification: Triceratops is the best-known genus of Ceratopsidae, a family of large, mostly North American ceratopsians. The exact relationship of Triceratops among the other ceratopsids has been debated over the years. The confusion stemmed mainly from the combination of a short, solid frill (similar to that of Centrosaurinae), with long brow horns (more akin to Chasmosaurinae). In the first overview of ceratopsians, R. S. Lull hypothesized the existence of 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 when Lawrence Lambe, in 1915, formally described the first, short-frilled group as Centrosaurinae (including Triceratops), and the second, long-frilled group as Chasmosaurinae.
In 1949, Charles Mortram Sternberg was the first to question this position, proposing instead that Triceratops was more closely related to Arrhinoceratops and Chasmosaurus based on skull and horn features, making Triceratops a chasmosaurine ("ceratopsine" in his usage) genus. He was largely ignored, with John Ostrom and later David Norman placing Triceratops within the Centrosaurinae.
Paleobiology:
Social Behavior: The Triceratops genus was found all around North America and was one of the most successful herbivores of their time, with herds of them roaming all across the Cretaceous landscape.
Although Triceratops is commonly portrayed as a herding animal, there is currently little evidence to suggest that they lived in herds. While several other ceratopsians are known for bone beds preserving bones from two to hundreds or even thousands of individuals, there is currently only one documented bonebed dominated by Triceratops bones: a site in southeastern Montana with the remains of three juveniles. It may be significant that only juveniles were present. In 2012, a group of three Triceratops in relatively complete condition, each of varying sizes from a full-grown adult to a small juvenile, were found near Newcastle, Wyoming. The remains are currently under excavation by paleontologist Peter Larson and a team from the Black Hills Institute. It is believed that the animals were traveling as a family unit, but it remains unknown if the group consists of a mated pair and their offspring, or two females and a juvenile they were caring for. The remains also show signs of predation or scavenging from Tyrannosaurus, particularly on the largest specimen, with the bones of the front limbs showing breakage and puncture wounds from Tyrannosaurus teeth. In 2020, Illies and Fowler described the co-ossified distal caudal vertebrae of Triceratops. According to them, this pathology could have arisen after one Triceratops accidentally stepped on the tail of another member of the herd.
For many years, Triceratops' finds were known only from solitary individuals. These remains are very common. For example, Bruce Erickson, a paleontologist at the Science Museum of Minnesota, has reported having seen 200 specimens of T. prorsus in the Hell Creek Formation of Montana. 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, 66 mya) of western North America, it is regarded as one of the dominant herbivores of the time, if not the most dominant. In 1986, Robert Bakker estimated it as making up five-sixths 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.
Analysis of the endocranial anatomy of Triceratops suggests its sense of smell was poor compared to that of other dinosaurs. Its ears were attuned to low-frequency sounds, given the short cochlear lengths recorded in an analysis by Sakagami et al. This same study also suggests that Triceratops held its head about 45 degrees to the ground, an angle that would showcase the horns and frill most effectively that simultaneously allowed the animal to take advantage of food through grazing.
A 2022 study by Wiemann and colleagues of various dinosaur genera, including Triceratops, suggests that it had an ectothermic (cold-blooded) or gigantothermic metabolism, on par with that of modern reptiles. This was uncovered using the spectroscopy of lipoxidation signals, which are byproducts of oxidative phosphorylation and correlate with metabolic rates. They suggested that such metabolisms may have been common for ornithischian dinosaurs in general, with the group evolving towards ectothermy from an ancestor with an endothermic (warm-blooded) metabolism.
It seems that Triceratops lived in small, but tightly-knit family groups of seven or more in the Cretaceous. Triceratops are like elephants, with a hierarchy and matriarch. Unlike elephants though, adult male Trikes are allowed in the herd, often a dominant bull is the leader of the herd and he protects the herd from predators and rival males who dare challenge him.
Triceratops would defecate in huge pile mounds of dung which are communal latrines acting as scent posts to tell other Triceratops their status, receptive to mate, age, and gender.
The only time more appear to come together is during the mating season, when large numbers of them gather in forest clearings, with the females looking for suitable partners, and males fight and show off their strength to cement their mating priorities.
Dentition and Diet: Triceratops were herbivorous and, because of their low-slung head, their primary food was probably low-growing vegetation, although they may have been able to knock down taller plants with their horns, beak, and sheer bulk. The jaws were tipped with a deep, narrow beak, believed to have been better at grasping and plucking than biting.
Triceratops teeth were arranged in groups called batteries, which contained 36 to 40 tooth columns on each side of each jaw and 3 to 5 stacked teeth per column, depending on the size of the animal. This gives a range of 432 to 800 teeth, of which only a fraction was in use at any given time (as tooth replacement was continuous throughout the life of the animal). They functioned by shearing in a vertical to near-vertical orientation. The great size and numerous teeth of Triceratops suggest that they ate large volumes of fibrous plant material. Some researchers suggest it ate palms and cycads and others suggest it ate ferns, which then grew in prairies.
Some paleontologists, however, believe that Triceratops may have been an omnivore, sometimes scavenging on dead animals. There have been some observations of Triceratops gaining calcium and protein gnawing on bones from carcasses along with meat, sometimes eating small mammals, fish, reptiles, baby dinosaurs if given the chance, and birds. Baby triceratops would eat the dung left by their mothers to gain gut bacteria to better digest when they feed on solid plant matter.
Since the plants like cycads and ferns are considered poisonous to herbivores to counter the toxins, Triceratops would often visit clay licks either on the side of cliffs or in rare cases in underground caves. In the newly-forming Rocky Mountains, it is believed that there are limestone caves during the time of Triceratops, providing possible clay lick sites for the dinosaurs. Herds would regularly visit such caves to lick the clay that would protect their stomachs from the toxins of the plants they ate. This is seen in African Bush Elephants in Mount Elgon, Africa today, heading for caves to ingest minerals. This behavior is called geophagy (the consumption of soil) either to counteract and neutralize the toxins of the plants they ate or to supplement their diet with extra nutrients (animals that tend to do this usually live in areas or conditions where nutrition is poor and essential minerals are hard to come by).
Functions of the horn and frills: There has been much speculation over the functions of Triceratops' head adornments. The two main theories have revolved around use in combat and courtship display, with the latter now thought to be the most likely primary function.
Early on, Lull postulated that the frills may have served as anchor points for the jaw muscles to aid chewing by allowing increased size and power for the muscles. This has been put forward by other authors over the years, but later studies do not find evidence of large muscle attachments on the frill bones.
Triceratops were long thought to have used their horns and frills in combat with large predators, such as Tyrannosaurus, the idea being discussed first by Charles H. Sternberg in 1917 and 70 years later by Robert Bakker. There is evidence that Tyrannosaurus did have aggressive head-on encounters with Triceratops, based on partially healed tyrannosaur tooth marks on a Triceratops brow horn and squamosal. The bitten horn is also broken, with new bone growth after the break. Which animal was the aggressor, however, is unknown. Paleontologist Peter Dodson estimates that, in a battle against a bull Triceratops, the Triceratops had the upper hand and would successfully defend itself by inflicting fatal wounds on the Tyrannosaurus using its sharp horns. Tyrannosaurus is also known to have fed on Triceratops, as shown by a heavily tooth-scored Triceratops ilium and sacrum.
In addition to combat with predators using their horns, Triceratops are popularly 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 is disagreement about whether they did so. 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 2006 study finds no evidence for horn thrust injuries causing these forms of damage (with there being no evidence of infection or healing). Instead, non-pathological bone resorption, or unknown bone diseases, are suggested as causes. A newer study compared incidence rates of skull lesions and periosteal reaction in Triceratops and Centrosaurus, showing that these were consistent with Triceratops using its horns in combat and the frill being adapted as a protective structure, while lower pathology rates in Centrosaurus may indicate visual use over physical use of cranial ornamentation or a form of combat focused on the body rather than the head. The frequency of injury was found to be 14% in Triceratops. The researchers also concluded that the damage found on the specimens in the study was often too localized to be caused by bone disease. Histological examination reveals that the frill of Triceratops is composed of fibrolamellar bone. This contains fibroblasts that play a critical role in wound healing and is capable of rapidly depositing bone during remodeling.
One skull was found with a hole in the jugal bone, apparently a puncture wound sustained while the animal was alive, as indicated by signs of healing. The hole has a diameter close to that of the distal end of a Triceratops horn. This and other apparent healed wounds in the skulls of ceratopsians have been cited as evidence of non-fatal intraspecific competition in these dinosaurs. Another specimen, referred to as "Big John", has a similar fenestra to the squamosal caused by what appears to be another Triceratops horn and the squamosal bone shows signs of significant healing, further vindicating the hypothesis that this ceratopsian used its horns for intra-specific combat.
These horns could also clearly be used for fighting other Triceratops. To settle disputes, the males would lock horns, using their weight and experience to overpower the enemy and emerge victorious. This can result in all sorts of injuries, from snapped horns to even punctured frills, as was the case for the Big John specimen. Even so, as tough animals, Triceratops is expected to heal and recover from such injuries, as Big John, believed to be 60 years old at the time of its death, apparently did not die as a result of its large traumatic lesion.
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 would not account for the bizarre and extravagant variation seen in different members of Ceratopsidae, which would rather support the sexual display theory.
The theory that frills functioned as a sexual display was first proposed by Davitashvili in 1961 and has gained increasing acceptance since. Evidence that visual display was important, either in courtship or other social behavior, can be seen in the ceratopsians differing markedly in their adornments, making each species highly distinctive. Also, modern living creatures with such displays of horns and adornments use them similarly. A 2006 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 probably important for visual communication and species recognition in general. The use of exaggerated structures to enable dinosaurs to recognize their own species has been questioned, as no such function exists for such structures in modern species.
Based on our Rescue Team's Observations confirmed some of the evidence from the fossil record, The Triceratops used their horns to defend themselves from predators during the T. Rex pack attack, and for fighting for mates as we observed two young bulls sparring with one another before being told off by the Dominant Bull. We also noticed individual variations among the herd with horns curving downwards or forward curving upward horns; we now know its sexual dimorphism with the downward thick curving horn individuals being males and the thin forward curving upwards individuals being females. Another characteristic is that some individuals have horns that have worn down or cut off from the tips, this is mostly seen in males as they often fight for dominance fighting for a mate, and fighting off predators. The frills are covered in scaly keratin and were more brightly colored with scar marks in the males compared to the duller colors of the females and juveniles.
Reproduction: They can go surprisingly long without water and lay thick eggs to protect them from small predators like Pectinodons and Acheroraptors. The herd would stay in one area where the eggs would hatch, then leave once the eggs hatched. The young Triceratops would either follow or get left behind. Triceratops are born able to walk like wildebeest and horses, so almost always the young follow.
Triceratops would gather in forest clearings in large numbers where males joust and spare one another to mate with the females, and based on our observations, females often favor older and experienced males with colorful frills that often darken with age, scar-covered, frills with wounds like bite marks from another predator like T. Rex, and worn down or cut off horns.
Growth and ontogeny: In 2006, the first extensive ontogenetic study of Triceratops was published in the journal Proceedings of the Royal Society. The study, by John R. Horner and Mark Goodwin, found that individuals of Triceratops could be divided into four general ontogenetic groups: babies, juveniles, subadults, and adults. With a total number of 28 skulls studied, the youngest was only 38 centimeters (15 in) long. Ten of the 28 skulls could be placed in order in a growth series with one representing each age. Each of the four growth stages was found to have identifying features. Multiple ontogenetic trends were discovered, including the size reduction of the epoccipitals, development, and reorientation of postorbital horns, and hollowing out of the horns.
Torosaurus as a growth stage of Triceratops: There has been a debate in the paleontology community that another similar dinosaur to Triceratops called Torosaurus represented the adult stage of Triceratops.
Torosaurus is a ceratopsid genus first identified from a pair of skulls in 1891, two years after the identification of Triceratops by Othneil Charles Marsh. The genus Torosaurus resembles Triceratops in geological age, distribution, anatomy, and size, so it has been recognized as a close relative. Its distinguishing features are an elongated skull and the presence of two ovular fenestrae in the frill. Paleontologists investigating dinosaur ontogeny in Montana's Hell Creek Formation have recently presented evidence that the two represent a single genus.
Paleoecology: Triceratops lived during the Late Cretaceous of western North America, its fossils coming from the Evanston Formation, Scollard Formation, Laramie Formation, Lance Formation, Denver Formation, and Hell Creek Formation. These fossil formations date back to the time of the Cretaceous–Paleogene extinction event, which has been dated to 66 ± 0.07 million years ago. Many animals and plants have been found in these formations, but mostly from the Lance Formation and Hell Creek Formation. Triceratops was one of the last ceratopsian genera to appear before the end of the Mesozoic. The related Torosaurus and more distantly related diminutive Leptoceratops were also present, though their remains have been rarely encountered.
Theropods from these formations include genera of dromaeosaurids, tyrannosaurids, ornithomimids, troodontids, avialans, and caenagnathids. Dromaeosaurids from the Hell Creek Formation are Acheroraptor and Dakotaraptor. Indeterminate dromaeosaurs are known from other fossil formations. Common teeth previously referred to as Dromaeosaurus and Saurornitholestes were considered to be those of Acheroraptor. The tyrannosaurids from the formation are Nanotyrannus and Tyrannosaurus, although the former is most likely a junior synonym of the latter. Among ornithomimids are the genera Struthiomimus and Ornithomimus. An undescribed animal named "Orcomimus" could be from the formation. Troodontids are only represented by Pectinodon and Paronychodon in the Hell Creek Formation with a possible species of Troodon from the Lance Formation. One species of unknown coelurosaur is known from teeth in Hell Creek and similar formations by a single species, Richardoestesia. Only three oviraptorosaurs are from the Hell Creek Formation: Anzu, Leptorhynchos, and a giant species of caenagnathid, very similar to Gigantoraptor, from South Dakota. However, only fossilized footprints were discovered. The avialans known from the formation are Avisaurus, multiple species of Brodavis, and several other species of hesperornithiformes, as well as several species of true birds, including Cimolopteryx.
Interactions with other Dinosaurs: They form mixed herds with Torosaurus Latus alongside Leptoceratops, Edmontosaurus, Ornithomimus, Alamosaurus, Ankylosaurus, Anzu, Denversaurus, Pachycephalosaurus, and Thescelosaurus browsing alongside one another while on the lookout for predators.
They have extremely hostile reactions towards predators like Tyrannosaurs, Dakotaraptors, Dromaeosaurus, Acheroraptors, and Pectinodons which feed on them and their young.
Tyrannosaurus had its job cut out for trying to hunt these creatures and being their main predator. Due to the long brow horns, frill, and herding behavior that is similar to Africa's Cape buffalo. Once one is provoked, the entire herd would attack. Normally a herd would circle their young to protect them while adults form a barrier wall with their frills and horns bellowing at the predators. The males are especially hostile to Tyrannosaurus, sometimes even killing Tyrannosaurus in a matter of minutes especially solitary individuals and such battles either lead to a stalemate or death to either of them or both. Due to popular belief, Triceratops can not charge attackers with their horns. To charge at an attacker would lead to the horns being damaged, cracked, or even taken off. Instead, Triceratops will gore attackers from the sides or front on the belly. Another detail is that they are quite sensitive to low-frequency sounds and T. Rex would use that to their advantage making low-pitched rumbles to spook the herd.
Torosaurus often feed alongside Triceratops herds and with better vision and smell would alert the others to threats and during the ruts young bulls of both species would interact in an interspecies behavior when they spar with one another.
They normally stay away from Ankylosaurus, due to their club tails, but could live alongside them if need be. Young Triceratops that had been abandoned by their herds would create groups that followed Ankylosaurus for protection.
Pachycephalosaurus, Trierarchuncus, Ornithomimus, and Thescelosaurus follow the Triceratops herds for protection, often around the edges snapping up insects that have been disturbed by their large feet.
It turns out that on the bristle filaments quills algae would grow on them attracting moths, they get nutrients from the secretions of the skin and the algae present on the filaments, as well as protection from avian predators. Adult female moths leave the quills of the triceratops to lay eggs in the droppings The larvae would live in the dung and newly emerged moths later fly from the dung pile to find a Triceratops host. The moths would die on top of the triceratops providing fertilizer to the algae.
Triceratops could feed on washed-up dead fish like Paleopsephurus, Lonchidion, Lepisosteus, Melvius, and Myledaphus. Triceratops would sometimes feed on Casterolimulus the shallows because their shells provide calcium to build up their horns. When they feed on water plants or logs they could encounter and would feed on Habrosaurus, Axestemys, Palaeobatrachus, Dinilysia, and young Basilemys and Scapherpeton. Although the latter two adults would nip and fight back.
Triceratops would steer clear of Didelphodon due to their aggression and sharp teeth. They may snack on Alphadon, Cimolestes, and young Meniscoessus if given the chance.
Triceratops would sometimes feed on the eggs and young of other dinosaurs if given the chance although they must protect their own eggs from small predators alongside Ornithomimus and Anzu.
Birds like Brodavis and Avisaurus would perch on Triceratops pecking off the bugs like the moths off of them. Sometimes seeking a suitable moment, the larger dinosaur would unexpectedly drop all of its weight onto the bird, instantly crushing it. The Triceratops then eats the bird for a helpful boost of protein and minerals. The larger herbivore might even be doing this fun, as play behavior.
For the river predators, Borealosuchus, Champsosaurus, Thoracosaurus, and Brachychampsa adults aren't easy targets for them unless it's an injured one or dealing with a large float. Juveniles and Adolescents are vulnerable to attacks when drinking at the water's edge.
Extinction: Triceratops was one of the last-known non-avian dinosaurs alongside Tyrannosaurus and became extinct in the Cretaceous–Paleogene extinction event 66 million years ago. After the large asteroid alongside smaller asteroids, comets, and meteors came with it headed in the direction of Earth. With the sun blocked off causing plants to die off leading to the dying off of herbivores like Triceratops, they would be a feast for predators like T. Rex, but eventually, they will starve themselves into extinction.
Cultural Significance: Triceratops is the official state fossil of South Dakota. It is also the official state dinosaur of Wyoming. In 1942, Charles R. Knight painted a mural incorporating a confrontation between a Tyrannosaurus and a Triceratops in the Field Museum of Natural History for the National Geographic Society, establishing them as enemies in the popular imagination. Paleontologist Robert Bakker said of the imagined rivalry between Tyrannosaurus and Triceratops, "No matchup between predator and prey has ever been more dramatic. It's somehow fitting that those two massive antagonists lived out their co-evolutionary belligerence through the last days of the last epoch of the Age of Dinosaurs."
"I have seen the dueling dinosaurs display featuring Triceratops dueling with its arch-rival predator Tyrannosaurus at the Natural History Museum of Los Angeles both outside as a statute display and at the center of the Museum when you enter." -Thomas Tran
Danger Tip: They are a peaceful, but short-tempered species, they are less docile than Torosaurus. They are highly aggravated by loud objects, especially motorcycles, and tolerate trucks and jeeps, but run away at the sight of helicopters above. If you are seen in front of them, even their young, a scout, mother, or lead bull would charge at you sometimes with the whole herd until you are gone. If caught you'll be trampled, gored by their horns, tossed into the air, and bitten off by their sharp beaks. The best way to avoid them is to run to the tallest tree or a high place.
Significant Events: A herd of Triceratops was first encountered alongside other herbivores gathered at a clearing with a creek close to camp during Day 2 of the Rescue Team's Mission. They were mostly browsing, drinking from the creek, youngsters played by head butting each other similar to goats, and young bulls tested each other as a way to build up their ranks only to be reminded by the loud bellow of the dominant bull who's in charge.
The Next day, a pack of Tyrannosaurus attacked the multi-species herd, the Triceratops herd circled their young bellowing at their attackers and charging and shoving with their horns and frills, one juvenile has left behind and tried to rejoin them only to be grabbed by a large adult female Tyrannosaurus, luckily its mother came to the rescue and gore the T. Rex on the left leg of its thigh caused the predator to let go of the youngster and both rejoined the herd and disappeared after that. The following day, The team searched for the female T. Rex and happened upon a dead individual who got separated and drowned in the confusion was drifting in a river and washed up on shore among the rocks, where it is found by the injured female T. Rex is unable to reach the carcass, and is beaten by a flock of Quetzalcoatlus lawsonii who scavenge the dead body.
On the day when the asteroid hits, the Triceratops herd were found alongside the other herbivores in the valley where they are pursued by the Female T. Rex stampede down the hill and is funneled by the river on the left side and a wall of fallen logs and debris into the portal to the park. They now reside in the Hell Creek Herbivore Paddock.
Hell Creek Herbivore Paddock: The herd lives in an expansive multi-species paddock alongside other herbivores replicating the Hell Creek Floodplain environment; it is mostly fern prairie clearing, open-canopy forests, and swamps where they can browse peacefully. They are supplemented with elephant feed, cow feed, low shrubs, ferns, cycads, banana leaves, watermelons, and pumpkins which they love immensely. It mostly has lower elevated moats in the surrounding areas, steel bar fencing in the holding areas, and a couple of viewing areas which are wooden pole fencing with the moat hidden by plants on the top edge. There is a large steel bar fencing in an elevated deep moat ravine that separates them from the T. Rex in the Hell Creek Multi-Species Paddock which is hidden to give the illusion these dinosaurs are in the same space. They share the paddock with the closely related Torosaurus, Thescelosaurus, Edmontosaurus, Ornithomimus, Alamosaurus, Pachycephalosaurus, and Denversaurus.
Notable Individuals:
Topsy: An adult male Triceratops, named after one of the Characters from the Land Before Time, he is the dominant bull and leader of the herd. He is described to be stern, stubborn, and aggressive as that's his job to protect the herd and defend his title from rival males, but he is caring towards his family, and he tends to keep the staff on their toes.
Tria: An adult female Triceratops she is kind, loving, and brave, though can also tend to be timid especially now living in the park. Tria is far more lively than her mate, but is also far more hedonistic, enjoying relaxing in warm mud wallows. She is also patient and understanding of her mate Topps and her daughter, Cera. She often helps calm Topps down when he gets frustrated.
Theo: An adolescent male Triceratops, he is quite playful, cheery, and mild-mannered, unlike his father. He likes to play with his younger sisters, especially Cera.
Cera: A juvenile female Triceratops named after one of the Main Characters from The Land Before Time, is described to be bossy, skeptical, and proud demeanor similar to her father, which covers up her caring and sensitive side, but has a fun-loving side if given proper stimulus first, like headbutting with her siblings and older brother.
Tricia: A young female hatchlingTriceratops named after one of the Characters from the Land Before Time, a cute and funny-looking Triceratops, she sticks close to her mother and siblings and looks up to her older sister, Cera, and brother, Theo.
Conclusion: The Triceratops of Prehistoric Park are another iconic dinosaur alongside its predatory archrival Tyrannosaurus known to the public. As long as a Triceratops horridus is not disturbed, it is safe to observe, and hopefully, in Prehistoric Park these dinosaurs are here to stay in public viewing for generations to come.
The Field Guide might take a long time, like structuring and writing descriptions of the creatures, but also my time in college and spending time with my family. So you can suggest additional information quotes, descriptions, and natural or speculative behaviors for the prehistoric animals that I can edit and you send your suggestions either in reviews or Private Messages.
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