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149-602: Ceratosaurus / ˌ s ɛr ə t oʊ ˈ s ɔːr ə s / (from Greek κέρας/κέρατος, keras/keratos meaning "horn" and σαῦρος sauros meaning "lizard") was a carnivorous theropod dinosaur that lived in the Late Jurassic period ( Kimmeridgian to Tithonian ages ). The genus was first described in 1884 by American paleontologist Othniel Charles Marsh based on a nearly complete skeleton discovered in Garden Park, Colorado , in rocks belonging to

298-635: A carcharodontosaurid instead. In 2000 and 2006, paleontologists led by Octávio Mateus described a find from the Lourinhã Formation of central-west Portugal (ML 352) as a new specimen of Ceratosaurus , consisting of a right femur (upper thigh bone), a left tibia (shin bone), and several isolated teeth recovered from the cliffs of Valmitão beach, between the municipalities of Lourinhã and Torres Vedras . The bones were found embedded in yellow to brown, fine-grained sandstones, which were deposited by rivers as floodplain deposits and belong to

447-543: A pitch accent . In Modern Greek, all vowels and consonants are short. Many vowels and diphthongs once pronounced distinctly are pronounced as /i/ ( iotacism ). Some of the stops and glides in diphthongs have become fricatives , and the pitch accent has changed to a stress accent . Many of the changes took place in the Koine Greek period. The writing system of Modern Greek, however, does not reflect all pronunciation changes. The examples below represent Attic Greek in

596-411: A broad, articular surface, which is divided into two parts by a slight ridge. Projecting on either side are the lateral and medial epicondyles . The articular surface extends a little lower than the epicondyles, and is curved slightly forward; its medial extremity occupies a lower level than the lateral. The lateral portion of this surface consists of a smooth, rounded eminence, named the capitulum of

745-425: A distinct tingling sensation, and sometimes a significant amount of pain. It is sometimes popularly referred to as 'the funny bone', possibly due to this sensation (a "funny" feeling), as well as the fact that the bone's name is a homophone of 'humorous'. It lies posterior to the medial epicondyle, and is easily damaged in elbow injuries. The deltoid originates on the lateral third of the clavicle , acromion and

894-587: A dry season by theropods or by a collecting bias in other localities. In 1884, Marsh considered the nasal horn of Ceratosaurus to be a "most powerful weapon" for both offensive and defensive purposes and Gilmore, in 1920, concurred with this interpretation. The use of the horn as a weapon is now generally considered unlikely. In 1985, David Norman believed that the horn was "probably not for protection against other predators," but might instead have been used for intraspecific combat among male ceratosaurs contending for breeding rights. Gregory S. Paul , in 1988, suggested

1043-562: A fragmentary, disarticulated skeleton including the skull (UMNH VP 5278) in the Cleveland-Lloyd Dinosaur Quarry of Utah. This find represents one of the largest-known Ceratosaurus specimens. A second, articulated specimen including the skull (MWC 1) was discovered in 1976 by Thor Erikson, the son of paleontologist Lance Erikson, near Fruita, Colorado . A fairly complete specimen, it lacks lower jaws, forearms, and gastralia . The skull, although reasonably complete,

1192-477: A lack of contemporaneous evidence. Several theories exist about what Hellenic dialect groups may have existed between the divergence of early Greek-like speech from the common Proto-Indo-European language and the Classical period. They have the same general outline but differ in some of the detail. The only attested dialect from this period is Mycenaean Greek , but its relationship to the historical dialects and

1341-419: A lesser degree. Pamphylian Greek , spoken in a small area on the southwestern coast of Anatolia and little preserved in inscriptions, may be either a fifth major dialect group, or it is Mycenaean Greek overlaid by Doric, with a non-Greek native influence. Regarding the speech of the ancient Macedonians diverse theories have been put forward, but the epigraphic activity and the archaeological discoveries in

1490-402: A morph with a shortened snout, a high and wide skull, and short, backwards-projecting teeth, and a morph characterized by a longer snout, lower skull, and long, vertical teeth. Generally speaking, the greater the similarity between sympatric species regarding their morphology, physiology, and behavior, the more intense competition between these species will be. Henderson came to the conclusion that

1639-642: A nasal horn similar to that of Ceratosaurus . In 1926, Friedrich von Huene described this skull as Proceratosaurus (meaning "before Ceratosaurus "), assuming that it was an antecedent of the Late Jurassic Ceratosaurus . Today, Proceratosaurus is considered a basal member of Tyrannosauroidea , a much more derived clade of theropod dinosaurs. The nasal horn would have had evolved independently in both genera. Oliver Rauhut and colleagues, in 2010, grouped Proceratosaurus within its own family, Proceratosauridae . These authors also noted that

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1788-655: A possible species of Labrosaurus , Labrosaurus (?) stechowi . Other authors questioned the assignment of any of the Tendaguru finds to Ceratosaurus , noting that none of these specimens displays features diagnostic for that genus. In 2011, Rauhut found both C. roechlingi and Labrosaurus (?) stechowi to be possible ceratosaurids, but found them to be undiagnostic at genus level and designated them as nomina dubia (doubtful names). In 1990, Timothy Rowe and Jacques Gauthier mentioned yet another Ceratosaurus species from Tendaguru, Ceratosaurus ingens , which purportedly

1937-550: A prefix /e-/, called the augment . This was probably originally a separate word, meaning something like "then", added because tenses in PIE had primarily aspectual meaning. The augment is added to the indicative of the aorist, imperfect, and pluperfect, but not to any of the other forms of the aorist (no other forms of the imperfect and pluperfect exist). The two kinds of augment in Greek are syllabic and quantitative. The syllabic augment

2086-556: A presumed premaxillary tooth crown. This shows vertical striations on its inner side and lacks denticles on its front edge. These features are, in this combination, only known from Ceratosaurus . The authors, however, stressed that an assignment to Ceratosaurus is infeasible because the remains are scant and note that the assignment of the European and African material to Ceratosaurus has to be viewed with caution. In 2020, Soto and colleagues described additional Ceratosaurus teeth from

2235-429: A running animal with a horizontal posture and a tail that did not make contact with the ground. Because of the strong flattening of the fossils, Gilmore mounted the specimen, not as a free-standing skeleton, but as a bas-relief within an artificial wall. With the bones being partly embedded in a plaque, scientific access was limited. In the course of the renovation of the museum's dinosaur exhibition between 2014 and 2019,

2384-608: A separate historical stage, though its earliest form closely resembles Attic Greek , and its latest form approaches Medieval Greek . There were several regional dialects of Ancient Greek; Attic Greek developed into Koine. Ancient Greek was a pluricentric language , divided into many dialects. The main dialect groups are Attic and Ionic , Aeolic , Arcadocypriot , and Doric , many of them with several subdivisions. Some dialects are found in standardized literary forms in literature , while others are attested only in inscriptions. There are also several historical forms. Homeric Greek

2533-469: A shorter, taller, and stiffer body with longer legs. They would have been adapted for rapid running in open terrain and for preying upon large herbivorous dinosaurs such as sauropods and stegosaurs, but as speculated by Bakker and Bir, seasonally switched to aquatic prey items when the large herbivores were absent. However, this theory was challenged by Yun in 2019, suggesting Ceratosaurus was merely more capable of hunting aquatic prey than other theropods of

2682-424: A similar function and illustrated two Ceratosaurus engaged in a nonlethal butting contest. In 1990, Rowe and Gauthier went further, suggesting that the nasal horn of Ceratosaurus was "probably used for display purposes alone" and played no role in physical confrontations. If used for display, the horn likely would have been brightly colored. A display function was also proposed for the row of osteoderms running down

2831-630: A standard subject of study in educational institutions of the Western world since the Renaissance . This article primarily contains information about the Epic and Classical periods of the language, which are the best-attested periods and considered most typical of Ancient Greek. From the Hellenistic period ( c.  300 BC ), Ancient Greek was followed by Koine Greek , which is regarded as

2980-510: A vowel or /n s r/ ; final stops were lost, as in γάλα "milk", compared with γάλακτος "of milk" (genitive). Ancient Greek of the classical period also differed in both the inventory and distribution of original PIE phonemes due to numerous sound changes, notably the following: The pronunciation of Ancient Greek was very different from that of Modern Greek . Ancient Greek had long and short vowels ; many diphthongs ; double and single consonants; voiced, voiceless, and aspirated stops ; and

3129-534: Is 7 cm (2.8 in) in height. It is longer and lower in the skull of MWC 1. In the living animal, the horn would likely have been more elongated due to its keratinous sheath. Behind the nasal horn, the nasal bones formed an ovalur groove. Both this groove and the nasal horn serve as features to distinguish Ceratosaurus from related genera. In addition to the large nasal horn, Ceratosaurus possessed smaller, semicircular, bony ridges in front of each eye, similar to those of Allosaurus . These ridges were formed by

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3278-570: Is a literary form of Archaic Greek (derived primarily from Ionic and Aeolic) used in the epic poems , the Iliad and the Odyssey , and in later poems by other authors. Homeric Greek had significant differences in grammar and pronunciation from Classical Attic and other Classical-era dialects. The origins, early form and development of the Hellenic language family are not well understood because of

3427-407: Is a rounded eminence forming the lateral part of the distal humerus. The head of the radius articulates with the capitulum. The trochlea is spool-shaped medial portion of the distal humerus and articulates with the ulna. The epicondyles are continuous above with the supracondylar ridges. The medial supracondylar crest forms the sharp medial border of the distal humerus continuing superiorly from

3576-418: Is added to stems beginning with consonants, and simply prefixes e (stems beginning with r , however, add er ). The quantitative augment is added to stems beginning with vowels, and involves lengthening the vowel: Some verbs augment irregularly; the most common variation is e → ei . The irregularity can be explained diachronically by the loss of s between vowels, or that of the letter w , which affected

3725-666: Is called 'East Greek'. Arcadocypriot apparently descended more closely from the Mycenaean Greek of the Bronze Age. Boeotian Greek had come under a strong Northwest Greek influence, and can in some respects be considered a transitional dialect, as exemplified in the poems of the Boeotian poet Pindar who wrote in Doric with a small Aeolic admixture. Thessalian likewise had come under Northwest Greek influence, though to

3874-448: Is considered by some linguists to have been closely related to Greek . Among Indo-European branches with living descendants, Greek is often argued to have the closest genetic ties with Armenian (see also Graeco-Armenian ) and Indo-Iranian languages (see Graeco-Aryan ). Ancient Greek differs from Proto-Indo-European (PIE) and other Indo-European languages in certain ways. In phonotactics , ancient Greek words could end only in

4023-408: Is evident and that the fusion is unusual, but likely not pathological. Ronald Ratkevich, in 1976, argued that this fusion had limited the running ability of the animal, but this claim was rejected by Paul in 1988, who noted that the same feature occurs in many fast-moving animals of today, including ground birds and ungulates. A 1999 analysis by Darren Tanke and Bruce Rothschild suggested that the fusion

4172-444: Is located posteroinferior to the deltoid tuberosity. The inferior boundary of the spiral groove is continuous distally with the lateral border of the shaft. The nutrient foramen of the humerus is located in the anteromedial surface of the humerus. The nutrient arteries enter the humerus through this foramen. The distal or lower extremity of the humerus is flattened from before backward, and curved slightly forward; it ends below in

4321-452: Is now Tanzania . Although commonly considered the most important African dinosaur locality, large theropod dinosaurs are only known through few and very fragmentary remains. In 1920, German paleontologist Werner Janensch assigned several dorsal vertebrae from the quarry "TL" to Ceratosaurus , as Ceratosaurus sp. (of uncertain species). In 1925, Janensch named a new species of Ceratosaurus , C. roechlingi , based on fragmentary remains from

4470-426: Is placed laterally. The greater tubercle is where supraspinatus , infraspinatus and teres minor muscles are attached. The crest of the greater tubercle forms the lateral lip of the bicipital groove and is the site for insertion of pectoralis major . The greater tubercle is just lateral to the anatomical neck. Its upper surface is rounded and marked by three flat impressions: the highest of these gives insertion to

4619-610: Is regarded as one of the richest fossil sites of the Morrison Formation . Numerous dinosaur fossils had been recovered from this quarry even before the discovery of Ceratosaurus , most notably a nearly complete specimen of Allosaurus (USNM 4734) in 1883 and 1884. After excavation, the specimen was shipped to the Peabody Museum of Natural History in New Haven , where it was studied by Marsh, who described it as

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4768-403: Is slightly constricted and is termed the anatomical neck, in contradistinction to a constriction below the tubercles called the surgical neck which is frequently the seat of fracture. Fracture of the anatomical neck rarely occurs. The diameter of the humeral head is generally larger in men than in women. The anatomical neck ( collum anatomicum ) is obliquely directed, forming an obtuse angle with

4917-606: Is under debate. Some analyses considered Ceratosaurus as the most derived of the basal members, forming the sister taxon of Abelisauroidea. Oliver Rauhut, in 2004, proposed Genyodectes as the sister taxon of Ceratosaurus , as both genera are characterized by exceptionally long teeth in the upper jaw. Rauhut grouped Ceratosaurus and Genyodectes within the family Ceratosauridae, which was followed by several later accounts. Shuo Wang and colleagues, in 2017, concluded that Noasauridae were not nested within Abelisauroidea as

5066-518: Is usually reduced to a dewclaw that does not touch the ground, is not preserved in the holotype. Marsh, in his original 1884 description, assumed that this digit was lost in Ceratosaurus , but Charles Gilmore , in his 1920 monograph, noted an attachment area on the second metatarsal demonstrating the presence of this digit. Uniquely among theropods, Ceratosaurus possessed small, elongated, and irregularly formed osteoderms (skin bones) along

5215-461: The Ceratosaurus specimen. In 1920, Charles Gilmore published an extensive redescription of this and the other theropod specimens received from New Haven, including the nearly complete Allosaurus specimen recovered from the same quarry. In an 1892 paper, Marsh published the first skeletal reconstruction of Ceratosaurus , which depicts the animal at 22 ft (6.7 m) in length and 12 ft (3.7 m) in height. As noted by Gilmore in 1920,

5364-711: The Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek ( c.  1400–1200 BC ), Dark Ages ( c.  1200–800 BC ), the Archaic or Epic period ( c.  800–500 BC ), and the Classical period ( c.  500–300 BC ). Ancient Greek was the language of Homer and of fifth-century Athenian historians, playwrights, and philosophers . It has contributed many words to English vocabulary and has been

5513-708: The Greek region of Macedonia during the last decades has brought to light documents, among which the first texts written in Macedonian , such as the Pella curse tablet , as Hatzopoulos and other scholars note. Based on the conclusions drawn by several studies and findings such as Pella curse tablet , Emilio Crespo and other scholars suggest that ancient Macedonian was a Northwest Doric dialect , which shares isoglosses with its neighboring Thessalian dialects spoken in northeastern Thessaly . Some have also suggested an Aeolic Greek classification. The Lesbian dialect

5662-493: The Morrison Formation . The type species is Ceratosaurus nasicornis . The Garden Park specimen remains the most complete skeleton known from the genus and only a handful of additional specimens have been described since. Two additional species, Ceratosaurus dentisulcatus and Ceratosaurus magnicornis , were described in 2000 from two fragmentary skeletons from the Cleveland-Lloyd Quarry of Utah and from

5811-401: The entepicondylar foramen to allow the passage of nerves and blood vessels. During embryonic development, the humerus is one of the first structures to ossify, beginning with the first ossification center in the shaft of the bone. Ossification of the humerus occurs predictably in the embryo and fetus, and is therefore used as a fetal biometric measurement when determining gestational age of

5960-472: The intertubercular groove of the humerus. They work to adduct and medially, or internally, rotate the humerus. The infraspinatus and teres minor insert on the greater tubercle, and work to laterally, or externally, rotate the humerus. In contrast, the subscapularis muscle inserts onto the lesser tubercle and works to medially, or internally, rotate the humerus. The biceps brachii , brachialis , and brachioradialis (which attaches distally) act to flex

6109-501: The present , future , and imperfect are imperfective in aspect; the aorist , present perfect , pluperfect and future perfect are perfective in aspect. Most tenses display all four moods and three voices, although there is no future subjunctive or imperative. Also, there is no imperfect subjunctive, optative or imperative. The infinitives and participles correspond to the finite combinations of tense, aspect, and voice. The indicative of past tenses adds (conceptually, at least)

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6258-400: The supraspinatus muscle ; the middle to the infraspinatus muscle ; the lowest one, and the body of the bone for about 2.5 cm. below it, to the teres minor muscle . The lateral surface of the greater tubercle is convex, rough, and continuous with the lateral surface of the body. The lesser tubercle ( tuberculum minus ; lesser tuberosity) is smaller, anterolaterally placed to the head of

6407-1031: The 5th century BC. Ancient pronunciation cannot be reconstructed with certainty, but Greek from the period is well documented, and there is little disagreement among linguists as to the general nature of the sounds that the letters represent. /oː/ raised to [uː] , probably by the 4th century BC. Greek, like all of the older Indo-European languages , is highly inflected. It is highly archaic in its preservation of Proto-Indo-European forms. In ancient Greek, nouns (including proper nouns) have five cases ( nominative , genitive , dative , accusative , and vocative ), three genders ( masculine , feminine , and neuter ), and three numbers (singular, dual , and plural ). Verbs have four moods ( indicative , imperative , subjunctive , and optative ) and three voices (active, middle, and passive ), as well as three persons (first, second, and third) and various other forms. Verbs are conjugated through seven combinations of tenses and aspect (generally simply called "tenses"):

6556-495: The Archaic period of ancient Greek (see Homeric Greek for more details): Μῆνιν ἄειδε, θεά, Πηληϊάδεω Ἀχιλῆος οὐλομένην, ἣ μυρί' Ἀχαιοῖς ἄλγε' ἔθηκε, πολλὰς δ' ἰφθίμους ψυχὰς Ἄϊδι προΐαψεν ἡρώων, αὐτοὺς δὲ ἑλώρια τεῦχε κύνεσσιν οἰωνοῖσί τε πᾶσι· Διὸς δ' ἐτελείετο βουλή· ἐξ οὗ δὴ τὰ πρῶτα διαστήτην ἐρίσαντε Ἀτρεΐδης τε ἄναξ ἀνδρῶν καὶ δῖος Ἀχιλλεύς. The beginning of Apology by Plato exemplifies Attic Greek from

6705-675: The Classical period of ancient Greek. (The second line is the IPA , the third is transliterated into the Latin alphabet using a modern version of the Erasmian scheme .) Ὅτι [hóti Hóti μὲν men mèn ὑμεῖς, hyːmêːs hūmeîs,   Humerus The word "humerus" is derived from Late Latin humerus , from Latin umerus , meaning upper arm, shoulder, and is linguistically related to Gothic ams (shoulder) and Greek ōmos . The upper or proximal extremity of

6854-1004: The Cleveland-Lloyd Quarry and the Dinosaur National Monument in Utah, feature, respectively, the remains of at least three large theropods: Ceratosaurus , Allosaurus , and Torvosaurus . Likewise, Como Bluff and nearby localities in Wyoming contained remains of Ceratosaurus , Allosaurus , and at least one large megalosaurid. Ceratosaurus was a rare element of the theropod fauna, as it is outnumbered by Allosaurus at an average rate of 7.5 to 1 in sites where they co-occur. Several studies attempted to explain how these sympatric species could have reduced direct competition. Donald Henderson, in 1998, argued that Ceratosaurus co-occurred with two separate potential species of Allosaurus , which he denoted as "morphs":

7003-475: The Cleveland-Lloyd Quarry, which contains the long-snouted Allosaurus morph, but appears to be more common in both Garden Park and the Dry Mesa Quarry, in which it co-occurs with the short-snouted morph. Furthermore, Henderson suggested that Ceratosaurus could have avoided competition by preferring different prey items. The evolution of its extremely elongated teeth might have been a direct result of

7152-471: The Morrison Formation as opposed to being fully semiaquatic. In his 1986 popular book The Dinosaur Heresies , Bakker argued that the bones of the upper jaw were only loosely attached to the surrounding skull bones, allowing for some degree of movement within the skull, a condition termed cranial kinesis . Likewise, the bones of the lower jaw would have been able to move against each other and

7301-494: The abelisaurid Carnotaurus . The following cladogram showing the relationships of Ceratosaurus is based on the phylogenetic analysis conducted by Diego Pol and Oliver Rauhut in 2012: Berberosaurus Deltadromeus Spinostropheus Limusaurus Elaphrosaurus Ceratosaurus Genyodectes Noasauridae Abelisauridae A skull from the Middle Jurassic of England apparently displays

7450-401: The actions of lifting/pulling and pressing/pushing. Primitive fossils of amphibians had little, if any, shaft connecting the upper and lower extremities, making their limbs very short. In most living tetrapods , however, the humerus has a similar form to that of humans. In many reptiles and some mammals (where it is the primitive state), the lower extremity includes a large opening called

7599-511: The adult state of a single species. Oliver Rauhut, in 2003, and Matthew Carrano and Scott Sampson, in 2008, considered the anatomical differences cited by Madsen and Welles to support these additional species to represent ontogenetic (age-related) or individual variation. A further specimen (BYUVP 12893) was discovered in 1992 in the Agate Basin Quarry southeast of Moore, Utah , but still awaits description. The specimen, considered

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7748-415: The anterior border of the head of the radius, when the forearm is flexed. These fossæ are separated from one another by a thin, transparent lamina of bone, which is sometimes perforated by a supratrochlear foramen ; they are lined in the fresh state by the synovial membrane of the elbow-joint , and their margins afford attachment to the anterior and posterior ligaments of this articulation. The capitulum

7897-550: The aorist. Following Homer 's practice, the augment is sometimes not made in poetry , especially epic poetry. The augment sometimes substitutes for reduplication; see below. Almost all forms of the perfect, pluperfect, and future perfect reduplicate the initial syllable of the verb stem. (A few irregular forms of perfect do not reduplicate, whereas a handful of irregular aorists reduplicate.) The three types of reduplication are: Irregular duplication can be understood diachronically. For example, lambanō (root lab ) has

8046-419: The augment when it was word-initial. In verbs with a preposition as a prefix, the augment is placed not at the start of the word, but between the preposition and the original verb. For example, προσ(-)βάλλω (I attack) goes to προσ έ βαλoν in the aorist. However compound verbs consisting of a prefix that is not a preposition retain the augment at the start of the word: αὐτο(-)μολῶ goes to ηὐ τομόλησα in

8195-666: The best-known theropod discovered in America. In 1898 and 1899, the specimen was transferred to the National Museum of Natural History in Washington, DC , along with many other fossils originally described by Marsh. Only part of this material was fully prepared when it arrived in Washington. Subsequent preparation lasted from 1911 to the end of 1918. Packaging and shipment from New Haven to Washington caused some damage to

8344-411: The bite force concentrated at a smaller area due to the narrower skull. According to Henderson, the great similarities in skull shape between Ceratosaurus and the long-snouted Allosaurus morph indicate that these forms engaged in direct competition with each other. Therefore, Ceratosaurus might have been pushed out of habitats dominated by the long-snouted morph. Indeed, Ceratosaurus is very rare in

8493-421: The body cannot be inferred from this specimen. In his original description of the Ceratosaurus nasicornis holotype and subsequent publications, Marsh noted a number of characteristics that were unknown in all other theropods known at the time. Two of these features, the fused pelvis and fused metatarsus, were known from modern-day birds and, according to Marsh, clearly demonstrate the close relationship between

8642-564: The body midline. The strongly shortened metacarpals and phalanges of Ceratosaurus raise the question as to whether the hand retained the grasping function assumed for other basal theropods. Within Ceratosauria, an even more extreme hand reduction can be observed in abelisaurids, where the arm lost its original function , and in Limusaurus . In a 2016 paper on the anatomy of the Ceratosaurus hand, Carrano and Jonah Choiniere stressed

8791-449: The body. It is best marked in the lower half of its circumference; in the upper half it is represented by a narrow groove separating the head from the tubercles. The line separating the head from the rest of the upper end is called the anatomical neck. It affords attachment to the articular capsule of the shoulder-joint, and is perforated by numerous vascular foramens . Fracture of the anatomical neck rarely occurs. The anatomical neck of

8940-514: The bone casts into their proper position, and painting to match the original color of the bones. Both the Fruita and Cleveland-Lloyd specimens were described by Madsen and Samuel Paul Welles in a 2000 monograph, with the Utah specimen being assigned to the new species C. dentisulcatus and the Colorado specimen being assigned to the new species C. magnicornis . The name dentisulcatus refers to

9089-438: The center of Greek scholarship, this division of people and language is quite similar to the results of modern archaeological-linguistic investigation. One standard formulation for the dialects is: West vs. non-West Greek is the strongest-marked and earliest division, with non-West in subsets of Ionic-Attic (or Attic-Ionic) and Aeolic vs. Arcadocypriot, or Aeolic and Arcado-Cypriot vs. Ionic-Attic. Often non-West

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9238-648: The close resemblance to the condition seen in modern birds. The presence of this feature in Ceratosaurus became controversial in 1890, when Georg Baur speculated that the fusion in the holotype was the result of a healed fracture . This claim was repeated in 1892 by Cope, while arguing that C. nasicornis should be classified as a species of Megalosaurus due to insufficient anatomical differences between these genera. However, examples of fused metatarsals in dinosaurs that are not of pathological origin have been described since, including taxa more basal than Ceratosaurus . Osborn, in 1920, explained that no abnormal bone growth

9387-410: The competition with the long-snouted Allosaurus morph. Both species could also have preferred different parts of carcasses when acting as scavengers. The elongated teeth of Ceratosaurus could have served as visual signals facilitating the recognition of members of the same species or for other social functions. In addition, the large size of these theropods would have tended to decrease competition, as

9536-421: The crest of the spine of the scapula. It is inserted on the deltoid tuberosity of the humerus and has several actions including abduction, extension, and circumduction of the shoulder. The supraspinatus also originates on the spine of the scapula. It inserts on the greater tubercle of the humerus, and assists in abduction of the shoulder. The pectoralis major , teres major , and latissimus dorsi insert at

9685-615: The dialect of Sparta ), and Northern Peloponnesus Doric (including Corinthian ). All the groups were represented by colonies beyond Greece proper as well, and these colonies generally developed local characteristics, often under the influence of settlers or neighbors speaking different Greek dialects. After the conquests of Alexander the Great in the late 4th century BC, a new international dialect known as Koine or Common Greek developed, largely based on Attic Greek , but with influence from other dialects. This dialect slowly replaced most of

9834-404: The dorsal (back) vertebrae, were as tall as the vertebral centra were long. The sacrum, consisting of six fused sacral vertebrae , was arched upwards, with its vertebral centra strongly reduced in height in its middle portion, as is the case in some other ceratosaurians . The tail comprised around 50 caudal vertebrae and was about half of the animal's total length. In the holotype, it

9983-433: The elbow. (The biceps do not attach to the humerus.) The triceps brachii and anconeus extend the elbow, and attach to the posterior side of the humerus. The four muscles of supraspinatus, infraspinatus, teres minor and subscapularis form a musculo-ligamentous girdle called the rotator cuff . This cuff stabilizes the very mobile but inherently unstable glenohumeral joint . The other muscles are used as counterbalances for

10132-424: The evolutionary line leading to modern birds and is considered basal within theropods. Ceratosauria itself contains a group of derived (nonbasal) members of the families Noasauridae and Abelisauridae , which are bracketed within the clade Abelisauroidea , as well as a number of basal members, such as Elaphrosaurus , Deltadromeus , and Ceratosaurus . The position of Ceratosaurus within basal ceratosaurians

10281-415: The extremity. The grooved portion of the articular surface fits accurately within the semilunar notch of the ulna; it is broader and deeper on the posterior than on the anterior aspect of the bone, and is inclined obliquely downward and forward toward the medial side. At the shoulder, the head of the humerus articulates with the glenoid fossa of the scapula . More distally, at the elbow, the capitulum of

10430-548: The first digit would have been slightly turned in when flexed . A cast of the brain cavity of the holotype was made under Marsh's supervision, probably during preparation of the skull, allowing Marsh to conclude that the brain "was of medium size, but comparatively much larger than in the herbivorous dinosaurs". The skull bones, however, had been cemented together afterwards, so the accuracy of this cast could not be verified by later studies. A second, well preserved braincase had been found with specimen MWC 1 in Fruita, Colorado, and

10579-420: The genus outside of North America. Fragmentary remains have also been reported from Tanzania , Uruguay , and Switzerland , although their assignment to Ceratosaurus is currently not accepted by most paleontologists . Ceratosaurus was a medium-sized theropod. The original specimen is estimated to be 5.3 m (17 ft) or 5.69 m (18.7 ft) long, while the specimen described as C. dentisulcatus

10728-526: The genus. In a 2016 paper, Matthew Carrano and Jonah Choiniere suggested that one or more cartilaginous (not bony) carpals were probably present, as indicated by a gap present between the forearm bones and the metacarpals, as well as by the surface texture within this gap seen in the cast. In contrast to most more- derived theropods, which showed only three digits on each hand (digits I–III), Ceratosaurus retained four digits, with digit IV being reduced in size. The first and fourth metacarpals were short, while

10877-467: The great morphological similarity of the hand with those of other basal theropods, suggesting that it still fulfilled its original grasping function, despite its shortening. Although only the first phalanges are preserved, the second phalanges would have been mobile, as indicated by the well-developed articular surfaces, and the digits would likely have allowed a similar degree of motion as in other basal theropods. As in other theropods other than abelisaurids,

11026-561: The historical Dorians . The invasion is known to have displaced population to the later Attic-Ionic regions, who regarded themselves as descendants of the population displaced by or contending with the Dorians. The Greeks of this period believed there were three major divisions of all Greek people – Dorians, Aeolians, and Ionians (including Athenians), each with their own defining and distinctive dialects. Allowing for their oversight of Arcadian, an obscure mountain dialect, and Cypriot, far from

11175-476: The historical circumstances of the times imply that the overall groups already existed in some form. Scholars assume that major Ancient Greek period dialect groups developed not later than 1120 BC, at the time of the Dorian invasions —and that their first appearances as precise alphabetic writing began in the 8th century BC. The invasion would not be "Dorian" unless the invaders had some cultural relationship to

11324-411: The holotype, each half of the dentary , the tooth-bearing bone of the mandible , was equipped with 15 teeth, which are, however, poorly preserved. Both specimens MWC 1 and UMNH VP 5278 show only 11 teeth in each dentary, which were, as shown by the latter specimen, slightly straighter and less sturdy than those of the upper jaw. The exact number of vertebrae is unknown due to several gaps in

11473-441: The holotype. The back of the skull was more lightly built than in some other larger theropods due to extensive skull openings, yet the jaws were deep to support the proportionally large teeth. The lacrimal bone formed not only the back margin of the antorbital fenestra , a large opening between eye and bony nostril , but also part of its upper margin, unlike in members of the related Abelisauridae . The quadrate bone , which

11622-401: The holotype. The position of this plate on the body, however, is unknown. Specimen UMNH VP 5278 was also found with a number of osteoderms, which have been described as amorphous in shape. Although most of these ossicles were found at most 5 m apart from the skeleton, they were not directly associated with any vertebrae, unlike in the C. nasicornis holotype, so their original position on

11771-439: The humerus consists of the bone's large rounded head joined to the body by a constricted portion called the neck, and two eminences, the greater and lesser tubercles. The head ( caput humeri ), is nearly hemispherical in form. It is directed upward, medialward, and a little backward, and articulates with the glenoid cavity of the scapula to form the glenohumeral joint (shoulder joint) . The circumference of its articular surface

11920-412: The humerus ; it articulates with the cup-shaped depression on the head of the radius, and is limited to the front and lower part of the bone. Above the front part of the trochlea is a small depression, the coronoid fossa , which receives the coronoid process of the ulna during flexion of the forearm. Above the back part of the trochlea is a deep triangular depression, the olecranon fossa , in which

12069-404: The humerus articulates with the head of the radius , and the trochlea of the humerus articulates with the trochlear notch of the ulna . The axillary nerve is located at the proximal end, against the shoulder girdle. Dislocation of the humerus's glenohumeral joint has the potential to injure the axillary nerve or the axillary artery . Signs and symptoms of this dislocation include a loss of

12218-402: The humerus is an indentation distal to the head of the humerus on which the articular capsule attaches. The surgical neck is a narrow area distal to the tubercles that is a common site of fracture. It makes contact with the axillary nerve and the posterior humeral circumflex artery . The greater tubercle ( tuberculum majus ; greater tuberosity) is a large, posteriorly placed projection that

12367-476: The humerus. The lesser tubercle provides insertion to subscapularis muscle. Both these tubercles are found in the proximal part of the shaft. The crest of the lesser tubercle forms the medial lip of the bicipital groove and is the site for insertion of teres major and latissimus dorsi muscles. The lesser tuberosity, is more prominent than the greater: it is situated in front, and is directed medialward and forward. Above and in front it presents an impression for

12516-413: The insertion of the tendon of the subscapularis muscle . The tubercles are separated from each other by a deep groove, the bicipital groove (intertubercular groove; bicipital sulcus), which lodges the long tendon of the biceps brachii muscle and transmits a branch of the anterior humeral circumflex artery to the shoulder-joint. It runs obliquely downward, and ends near the junction of the upper with

12665-458: The lacrimal bones. In juveniles, all three horns were smaller than in adults and the two halves of the nasal horn core were not yet fused. The premaxillary bones , which formed the tip of the snout, contained merely three teeth on each side, less than in most other theropods. The maxillary bones of the upper jaw were lined with 15 blade-like teeth on each side in the holotype. The first eight of these teeth were very long and robust, but from

12814-469: The largest known from the genus, includes the front half of a skull, seven fragmentary pelvic dorsal vertebrae, and an articulated pelvis and sacrum. In 1999, Britt reported the discovery of a Ceratosaurus skeleton belonging to a juvenile individual. Discovered in Bone Cabin Quarry in Wyoming, it is 34% smaller than the C. nasicornis holotype and consists of a complete skull as well as 30% of

12963-479: The last ribs of the trunk, the humeri (upper arm bones), the distal finger bones of both hands, most of the right arm, most of the left leg, and most of the feet. The specimen was found encased in hard sandstone, leading to the skull and spine being heavily distorted during fossilization . The site of discovery, located in the Garden Park area north of Cañon City, Colorado , and known as the Felch Quarry 1,

13112-467: The latter and dinosaurs. To set the genus apart from Allosaurus , Megalosaurus , and coelurosaurs , Marsh made Ceratosaurus the only member of both a new family , Ceratosauridae , and a new infraorder , Ceratosauria. This was questioned in 1892 by Edward Drinker Cope , Marsh's archrival in the Bone Wars , who argued that distinctive features such as the nasal horn merely showed that C. nasicornis

13261-494: The left and right nasal bones . Only the bony horn core is known from fossils. In the living animal, this core would have supported a keratinous sheath. While the base of the horn core was smooth, its upper two-thirds were wrinkled and lined with grooves that would have contained blood vessels when alive. In the holotype, the horn core is 13 cm (5.1 in) long and 2 cm (0.79 in) wide at its base, but quickly narrows to only 1.2 cm (0.47 in) further up, and

13410-420: The long, low, and flexible body of Ceratosaurus and megalosaurids. Compared to other Morrison theropods, Ceratosaurus showed taller neural spines on the foremost tail vertebrae, which were vertical rather than inclined towards the back. Together with the deep chevron bones on the underside of the tail, they indicate a deep, "crocodile-like" tail possibly adapted for swimming. On the contrary, allosaurids feature

13559-478: The lower levels of the Porto Novo Member, which is thought to be late Kimmeridgian in age. Additional bones of this individual (SHN (JJS)-65), including a left femur, a right tibia, and a partial left fibula (calf bone), were since exposed due to progressing cliff erosion . Although initially part of a private collection, these additional elements became officially curated after the private collection

13708-413: The medial epicondyle. The lateral supracondylar crest forms the sharp lateral border of the distal humerus continuing superiorly from the lateral epicondyle. The medial portion of the articular surface is named the trochlea , and presents a deep depression between two well-marked borders; it is convex from before backward, concave from side to side, and occupies the anterior, lower, and posterior parts of

13857-461: The middle third of the bone. In the fresh state its upper part is covered with a thin layer of cartilage, lined by a prolongation of the synovial membrane of the shoulder-joint; its lower portion gives insertion to the tendon of the latissimus dorsi muscle . It is deep and narrow above, and becomes shallow and a little broader as it descends. Its lips are called, respectively, the crests of the greater and lesser tubercles ( bicipital ridges ), and form

14006-405: The midline of its body. Such osteoderms have been found above the neural spines of cervical vertebrae 4 and 5, as well as caudal vertebrae 4 to 10, and probably formed a continuous row that might have extended from the base of the skull to most of the tail. As suggested by Gilmore in 1920, their position in the rock matrix likely reflects their exact position in the living animal. The osteoderms above

14155-625: The nasal horn is incompletely preserved, opening the possibility that it represented the foremost portion of a more extensive head crest, as seen in some other proceratosaurids such as Guanlong . Within the Morrison and Lourinhã Formation, Ceratosaurus fossils are frequently found in association with those of other large theropods, including the megalosaurid Torvosaurus and the allosaurid Allosaurus . The Garden Park locality in Colorado contained, besides Ceratosaurus , fossils attributed to Allosaurus . The Dry Mesa Quarry in Colorado, as well as

14304-457: The new genus and species Ceratosaurus nasicornis in 1884. The name Ceratosaurus may be translated as "horn lizard" (from the Greek words κερας/κερατος , keras/keratos —"horn" and σαυρος / sauros —"lizard") and nasicornis with "nose horn" (from the Latin words nasus —"nose" and cornu —"horn"). Given the completeness of the specimen, the newly described genus was, at the time,

14453-418: The ninth tooth onward, they gradually decrease in size. As is typical for theropods, they featured finely serrated edges, which contained some 10 denticles per 5 mm (0.20 in) in the holotype. Specimen MWC 1 merely showed 11 to 12 and specimen UMNH VP 5278 showed 12 teeth in each maxilla. The teeth were more robust and more recurved in the latter specimen. In all specimens, the tooth crowns of

14602-434: The normal shoulder contour and a palpable depression under the acromion. The radial nerve follows the humerus closely. At the midshaft of the humerus, the radial nerve travels from the posterior to the anterior aspect of the bone in the spiral groove . A fracture of the humerus in this region can result in radial nerve injury. The ulnar nerve lies at the distal end of the humerus near the elbow. When struck, it can cause

14751-445: The number of possible prey items increases with size. Foster and Daniel Chure, in a 2006 study, concurred with Henderson that Ceratosaurus and Allosaurus generally shared the same habitats and preyed upon the same types of prey, meaning they likely had different feeding strategies to avoid competition. According to these researchers, this is also evidenced by different proportions of the skull, teeth, and arms. The distinction between

14900-508: The older dialects, although the Doric dialect has survived in the Tsakonian language , which is spoken in the region of modern Sparta. Doric has also passed down its aorist terminations into most verbs of Demotic Greek . By about the 6th century AD, the Koine had slowly metamorphosed into Medieval Greek . Phrygian is an extinct Indo-European language of West and Central Anatolia , which

15049-584: The older synonym Ceratosauroidea, which was hitherto rarely used. For Abelisauridae, Delcourt proposed a new definition that excludes Ceratosaurus , allowing for using the name in its traditional sense. Wang and colleagues furthermore found that Ceratosaurus and Genyodectes form a clade with the Argentinian genus Eoabelisaurus . Delcourt used the name Ceratosauridae to refer to this same clade, and suggested to define Ceratosauridae as containing all taxa that are more closely related to Ceratosaurus than to

15198-421: The parallel grooves present on the inner sides of the premaxillary teeth and the first three teeth of the lower jaw in that specimen. Magnicornis points to the larger nasal horn. The validity of both species, however, was questioned in subsequent publications. Brooks Britt and colleagues, in 2000, claimed that the C. nasicornis holotype was in fact a juvenile individual, with the two larger species representing

15347-487: The perfect stem eilēpha (not * lelēpha ) because it was originally slambanō , with perfect seslēpha , becoming eilēpha through compensatory lengthening. Reduplication is also visible in the present tense stems of certain verbs. These stems add a syllable consisting of the root's initial consonant followed by i . A nasal stop appears after the reduplication in some verbs. The earliest extant examples of ancient Greek writing ( c.  1450 BC ) are in

15496-414: The quadrate bone could swing outwards, spreading the lower jaw at the jaw joint. Taken together, these features would have allowed the animal to widen its jaws in order to swallow larger food items. In a 2008 study, Casey Holliday and Lawrence Witmer re-evaluated similar claims made for other dinosaurs, concluding that the presence of muscle-powered cranial kinesis cannot be proven for any dinosaur species and

15645-411: The quarry "Mw" encompassing a quadrate bone, a fibula, fragmentary caudal vertebrae, and other fragments. This specimen stems from an individual substantially larger than the C. nasicornis holotype. In their 2000 monograph, Madsen and Welles confirmed the assignment of these finds to Ceratosaurus . In addition, they ascribed several teeth to the genus, which had originally been described by Janensch as

15794-419: The remainder of the skeleton including a complete pelvis. Besides these five skeletal finds, fragmentary Ceratosaurus remains have been reported from various localities from stratigraphic zones 2 and 4-6 of the Morrison Formation, including some of the major fossil sites of the formation. Dinosaur National Monument , Utah, yielded an isolated right premaxilla (DNM 972). A large shoulder blade (scapulocoracoid)

15943-450: The same formation that further support their earlier interpretation. Ceratosaurus followed the body plan typical for large theropod dinosaurs. As a biped , it moved on powerful legs, while its arms were reduced in size. Specimen USNM 4735, the first discovered skeleton and holotype of Ceratosaurus nasicornis , was an individual 5.3 m (17 ft) or 5.69 m (18.7 ft) long according to separate sources. Whether this animal

16092-528: The second was slightly longer than the third. The metacarpus and especially the first phalanges were proportionally very short, unlike in most other basal theropods. Only the first phalanges of digits II, III, and IV are preserved in the holotype. The total number of phalanges and unguals (claw bones) is unknown. The anatomy of metacarpal I indicates that phalanges had originally been present on this digit as well. The pes (foot) consisted of three weight-bearing digits, numbered II–IV. Digit I, which in theropods

16241-406: The semicircular canals was enlarged, a feature generally found in bipedal animals. The orientation of the lateral semicircular canal indicates that the head and neck were held horizontally in neutral position. The holotype of C. nasicornis was found with its left metatarsals II to IV fused together. Marsh, in 1884, dedicated a short article to this, at the time, unknown feature in dinosaurs, noting

16390-627: The sense of smell, are well-preserved. While similar to those of Allosaurus , they were smaller than in Tyrannosaurus , which is thought to have been equipped with a very keen sense of smell. The semicircular canals , which are responsible for the sense of balance and therefore allow for inferences on habitual head orientation and locomotion, are similar to those found in other theropods. In theropods, these structures are generally conservative, suggesting that functional requirements during locomotion have been similar across species. The foremost of

16539-403: The shaft has a crest, beginning just below the surgical neck of the humerus and extends till the superior tip of the deltoid tuberosity. This is where the lateral head of triceps brachii is attached. The radial sulcus, also known as the spiral groove is found on the posterior surface of the shaft and is a shallow oblique groove through which the radial nerve passes along with deep vessels. This

16688-502: The short-snouted Allosaurus morph occupied a different ecological niche from both the long-snouted morph and Ceratosaurus . The shorter skull in this morph would have reduced bending moments occurring during biting, thus increased bite force, comparable to the condition seen in cats. Ceratosaurus and the other Allosaurus morph, though, had long-snouted skulls, which are better compared to those of dogs. The longer teeth would have been used as fangs to deliver quick, slashing bites, with

16837-437: The size of the striations. While the position of the bite marks on the herbivorous dinosaurs is consistent with predation or early access to remains, bite marks found on Allosaurus material suggest scavenging, either from the other theropods or from another Allosaurus . The unusually high concentration of theropod bite marks compared to other assemblages could be explained either by a more complete utilization of resources during

16986-424: The snout to the occipital condyle , which connects to the first cervical vertebra. The width of this skull is difficult to reconstruct, as it is heavily distorted, and Gilmore's 1920 reconstruction was later found to be too wide. The fairly complete skull of specimen MWC 1 was estimated to have been 60 cm (24 in) long and 16 cm (6.3 in) wide. This skull was somewhat more elongated than that of

17135-467: The specimen was dismantled and freed from the encasing plaque. In the new exhibition, which was set to open in 2019, the mount was planned to be replaced by a free-standing cast and the original bones were to be stored in the museum collection to allow full access for scientists. After the discovery of the holotype of C. nasicornis , a significant Ceratosaurus find was not made until the early 1960s, when paleontologist James Madsen and his team unearthed

17284-408: The spine of the Ceratosaurus nasicornis holotype. At least 20 vertebrae formed the neck and back in front of the sacrum . In the middle portion of the neck, the centra (bodies) of the vertebrae were as long as they were tall, while in the front and rear portions of the neck, the centra were shorter than their height. The upwards projecting neural spines were comparatively large and, in

17433-595: The strongly elongated teeth. The geologically older genus Proceratosaurus from England , although originally described as a presumed antecedent of Ceratosaurus , was later found to be an early tyrannosauroid. Ceratosaurus shared its habitat with other large theropod genera, including Torvosaurus and Allosaurus , and it has been suggested that these theropods occupied different ecological niches to reduce competition. Ceratosaurus may have preyed upon plant-eating dinosaurs, although some paleontologists suggested that it hunted aquatic prey such as fish. The nasal horn

17582-405: The summit of the olecranon is received in extension of the forearm. The coronoid fossa is the medial hollow part on the anterior surface of the distal humerus. The coronoid fossa is smaller than the olecranon fossa and receives the coronoid process of the ulna during maximum flexion of the elbow. Above the front part of the capitulum is a slight depression, the radial fossa , which receives

17731-517: The syllabic script Linear B . Beginning in the 8th century BC, however, the Greek alphabet became standard, albeit with some variation among dialects. Early texts are written in boustrophedon style, but left-to-right became standard during the classic period. Modern editions of ancient Greek texts are usually written with accents and breathing marks , interword spacing , modern punctuation , and sometimes mixed case , but these were all introduced later. The beginning of Homer 's Iliad exemplifies

17880-430: The tail were found separated from the neural spines by 25 mm (0.98 in) to 38 mm (1.5 in), possibly accounting for skin and muscles present in between, while those of the neck were much closer to the neural spines. Apart from the body midline, the skin contained additional osteoderms, as indicated by a 58 mm (2.3 in) by 70 mm (2.8 in) large, roughly quadrangular plate found together with

18029-466: The trunk was depicted much too long in this reconstruction, incorporating at least six dorsal vertebrae too many. This error was repeated in several subsequent publications, including the first life reconstruction, which was drawn in 1899 by Frank Bond under the guidance of Charles R. Knight , but not published until 1920. A more accurate life reconstruction, published in 1901, was produced by Joseph M. Gleeson , again under Knight's supervision. The holotype

18178-479: The two Allosaurus morphs, however, was questioned by some later studies. Kenneth Carpenter , in a 2010 study, found that short-snouted individuals of Allosaurus from the Cleveland-Lloyd Quarry represent cases of extreme individual variation rather than a separate taxon. Furthermore, the skull of USNM 4734 from the Garden Park locality, which formed the basis for Henderson's analysis of the short-snouted morph,

18327-484: The upper jaws were exceptionally long. In specimen UMNH VP 5278, they measured up to 9.3 cm (3.7 in) long, which is equal to the minimum height of the lower jaw. In the holotype, they are 7 cm (2.8 in) in length, which even surpasses the minimum height of the lower jaw. In other theropods, a comparable tooth length is only known from the possibly closely related Genyodectes . In contrast, several members of Abelisauridae feature very short tooth crowns. In

18476-434: The upper parts of the anterior and medial borders of the body of the bone. The body or shaft of the humerus is triangular to cylindrical in cut section and is compressed anteroposteriorly. It has 3 surfaces, namely: Its three borders are: The deltoid tuberosity is a roughened surface on the lateral surface of the shaft of the humerus and acts as the site of insertion of deltoideus muscle. The posterorsuperior part of

18625-624: The validity of C. dentisulcatus , assigned the specimen to Ceratosaurus aff. Ceratosaurus nasicornis . Other reports include a single tooth found in Moutier , Switzerland . Originally named by Janensch in 1920 as Labrosaurus meriani , the tooth was later assigned Ceratosaurus sp. (of unknown species) by Madsen and Welles. In 2008, Matías Soto and Daniel Perea described teeth from the Tacuarembó Formation in Uruguay , including

18774-404: The vicinity of Fruita, Colorado . The validity of these additional species has been questioned, however, and all three skeletons possibly represent different growth stages of the same species. In 1999, the discovery of the first juvenile specimen was reported. In 2000, a partial specimen was excavated and described from the Lourinhã Formation of Portugal , providing evidence for the presence of

18923-517: The years, separate authors classified Ceratosaurus within Deinodontidae , Megalosauridae , Coelurosauria , Carnosauria , and Deinodontoidea . In his 1920 revision, Gilmore argued that the genus was the most basal theropod known from after the Triassic , being not that closely related to any other contemporary theropod known at that time. It thus warrants its own family: Ceratosauridae. It

19072-404: Was CT-scanned by paleontologists Kent Sanders and David Smith, allowing for reconstructions of the inner ear , gross regions of the brain, and cranial sinuses transporting blood away from the brain. In 2005, the researchers concluded that Ceratosaurus possessed a brain cavity typical for basal theropods and similar to that of Allosaurus . The impressions for the olfactory bulbs , which house

19221-480: Was Aeolic. For example, fragments of the works of the poet Sappho from the island of Lesbos are in Aeolian. Most of the dialect sub-groups listed above had further subdivisions, generally equivalent to a city-state and its surrounding territory, or to an island. Doric notably had several intermediate divisions as well, into Island Doric (including Cretan Doric ), Southern Peloponnesus Doric (including Laconian ,

19370-489: Was a distinct species, but were insufficient to justify a distinct genus. Consequently, he assigned C. nasicornis to the genus Megalosaurus , creating the new combination Megalosaurus nasicornis . Although Ceratosaurus was retained as a distinct genus in all subsequent analyses, its relationships remained controversial during the following century. Both Ceratosauridae and Ceratosauria were not widely accepted, with only few and poorly known additional members identified. Over

19519-458: Was claimed to be the largest yet discovered, although estimates have not been published. Another specimen, ML 352, discovered in Portugal in 2000, was estimated at 6 m (20 ft) in length and 600 kg (1,320 lb). The skull was quite large in proportion to the rest of its body. It measures 55 cm (22 in) in length in the C. nasicornis holotype, measured from the tip of

19668-432: Was connected to the lower jaw at its bottom end to form the jaw joint, was inclined so that the jaw joint was displaced backwards in relation to the occipital condyle. This also led to a broadening of the base of the lateral temporal fenestra , a large opening behind the eyes. The most distinctive feature was a prominent horn situated on the skull midline behind the bony nostrils, which was formed from fused protuberances of

19817-553: Was donated to the Sociedade de História Natural in Torres Vedras and were described in detail in 2015. The specimen was ascribed to the species Ceratosaurus dentisulcatus by Mateus and colleagues in 2006. A 2008 review by Carrano and Sampson confirmed the assignment to Ceratosaurus , but concluded that the assignment to any specific species is not possible at present. In 2015, Elisabete Malafaia and colleagues, who questioned

19966-401: Was erected by Janensch in 1920 and was based on 25 isolated, very large teeth up to 15 cm (5.9 in) in length. However, Janensch assigned this species to Megalosaurus , not to Ceratosaurus . Therefore, this name might be a simple copying error. Rauhut, in 2011, showed that Megalosaurus ingens was not closely related to either Megalosaurus or Ceratosaurus , but possibly represents

20115-427: Was estimated at 2.84 m (9.33 ft). The tail was deep from top to bottom due to its high neural spines and elongated chevrons , bones located below the vertebral centra. As in other dinosaurs, it counterbalanced the body and contained the massive caudofemoralis muscle, which was responsible for forward thrust during locomotion, pulling the upper thigh backwards when contracted . The scapula (shoulder blade)

20264-438: Was estimated by James Madsen to have been around 8.8 m (29 ft) long, but was later estimated at 7 m (23 ft) long. Its weight was calculated at 980 kg (2,160 lb), 452 kg (996 lb), and 700 kg (1,540 lb) in separate works. The second skeleton, MWC 1, was somewhat smaller than UMNH VP 5278 and might have weighed 275 kg (606 lb). The third, yet undescribed, specimen BYUVP 12893

20413-464: Was found disarticulated and is strongly flattened sideways. Although it was a large individual, it had not yet reached adult size, as indicated by unfused sutures between the skull bones. Scientifically accurate three-dimensional reconstructions of the skull for use in museum exhibits were produced using a complicated process including molding and casting of the individual original bones, correction of deformities, reconstruction of missing parts, assembly of

20562-426: Was fully grown is unclear. Othniel Charles Marsh , in 1884, suggested that this specimen weighed about half as much as the contemporary Allosaurus . In more recent accounts, this was revised to 418 kilograms (922 lb), 524 kg (1,155 lb), or 670 kg (1,480 lb). Three additional skeletons discovered in the latter half of the 20th century were substantially larger. The first of these, UMNH VP 5278,

20711-477: Was fused with the coracoid , forming a single bone without any visible demarcation between the two original elements. The C. nasicornis holotype was found with an articulated left arm including an incomplete hand. Although disarticulated during preparation, a cast had been made of the fossil beforehand to document the original relative positions of the bones. Carpal bones were not known from any specimen, leading some authors to suggest that they were lost in

20860-410: Was indeed pathological, confirming the earlier claim of Baur. Other reports of pathologies include a stress fracture in a foot bone assigned to the genus, as well as a broken tooth of an unidentified species of Ceratosaurus that shows signs of further wear received after the break. Ancient Greek Ancient Greek ( Ἑλληνῐκή , Hellēnikḗ ; [hellɛːnikɛ́ː] ) includes the forms of

21009-447: Was larger, at around 7 m (23 ft) long. Ceratosaurus was characterized by deep jaws that supported proportionally very long, blade-like teeth, a prominent, ridge-like horn on the midline of the snout, and a pair of horns over the eyes. The forelimbs were very short, but remained fully functional. The hand had four fingers with claws on the first three. The tail was deep from top to bottom. A row of small osteoderms (skin bones)

21158-887: Was later found to have been reconstructed too short. In a 2004 study, Robert Bakker and Gary Bir suggested that Ceratosaurus was primarily specialized in aquatic prey such as lungfish , crocodiles, and turtles. As indicated by a statistical analysis of shed teeth from 50 separate localities in and around Como Bluff, teeth of both Ceratosaurus and megalosaurids were most common in habitats in and around water sources such as wet floodplains , lake margins, and swamps. Ceratosaurus also occasionally occurred in terrestrial localities. Allosaurids, however, were equally common in terrestrial and aquatic habitats. From these results, Bakker and Bir concluded that Ceratosaurus and megalosaurids must have predominantly hunted near and within water bodies, with Ceratosaurus also feeding on carcasses of larger dinosaurs on occasion. The researchers furthermore noted

21307-787: Was likely absent in most. An Allosaurus pubic foot shows marks by the teeth of another theropod, probably Ceratosaurus or Torvosaurus . The location of the bone in the body (along the bottom margin of the torso and partially shielded by the legs) and the fact that it was among the most massive in the skeleton indicates that the Allosaurus was being scavenged. A bone assemblage in the Upper Jurassic Mygatt-Moore Quarry preserves an unusually high occurrence of theropod bite marks, most of which can be attributed to Allosaurus and Ceratosaurus , while others could have been made by Saurophaganax or Torvosaurus given

21456-466: Was mounted by Gilmore in 1910 and 1911. Since then, it was exhibited at the National Museum of Natural History. Most early reconstructions show Ceratosaurus in an upright posture, with the tail dragging on the ground. Gilmore's mount of the holotype, in contrast, was very ahead of its time. Inspired by the upper thigh bones, which were found angled against the lower leg, he depicted the mount as

21605-569: Was not until the establishment of cladistic analysis in the 1980s, however, that Marsh's original claim of Ceratosauria as a distinct group gained ground. In 1985, the newly discovered South American genera Abelisaurus and Carnotaurus were found to be closely related to Ceratosaurus . Gauthier, in 1986, recognized Coelophysoidea to be closely related to Ceratosaurus , although this clade falls outside of Ceratosauria in most recent analyses. Many additional members of Ceratosauria have been recognized since then. Ceratosauria split off early from

21754-426: Was present down the middle of the neck, back, and tail. Additional osteoderms were present at unknown positions on the animal's body. Ceratosaurus gives its name to Ceratosauria , a clade of theropod dinosaurs that diverged early on from the evolutionary lineage leading to modern birds . Within Ceratosauria, some paleontologists proposed it to be most closely related to Genyodectes from Argentina, which shares

21903-424: Was previously assumed, but instead were more basal than Ceratosaurus . Because noasaurids had been used as a fix point to define the clades Abelisauroidea and Abelisauridae, these clades would consequently include many more taxa per definition, including Ceratosaurus . In a subsequent 2018 study, Rafael Delcourt accepted these results, but pointed out that, as a consequence, Abelisauroidea would need to be replaced by

22052-425: Was probably not used as a weapon as was originally suggested by Marsh, but more likely was used solely for display. The first specimen, holotype USNM 4735, was discovered and excavated by farmer Marshall Parker Felch in 1883 and 1884. Found in articulation, with the bones still connected to each other, it was nearly complete, including the skull. Significant missing parts include an unknown number of vertebrae, all but

22201-755: Was reported from Como Bluff in Wyoming . Another specimen stems from the Dry Mesa Quarry of Colorado and includes a left scapulocoracoid, as well as fragments of vertebrae and limb bones. In Mygatt Moore Quarry, Colorado, the genus is known from teeth. From 1909 to 1913, German expeditions of the Berlin Museum für Naturkunde uncovered a diverse dinosaur fauna from the Tendaguru Formation in German East Africa , in what

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