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Uncovered
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A set of pterosaurs briefly shown in "Flamboyant Flyers". Clockwise from left: Tupuxuara leonardii, Sinopterus dongi, Thalassodromeus sethi, and Pteranodon longiceps.

Listed on this page are various animals that were only displayed and/or mentioned in the Uncovered segments of Prehistoric Planet, grouped by segments, which are in turn arranged by the order of the episodes each Uncovered segment is associated with.

Some Uncovered segments feature a few creatures known only from post-Mesozoic times leading up to the modern day (e.g. lions, elephants, horses, modern birds), or are otherwise not shown in a Mesozoic setting (e.g. cuttlefish). These would clearly not be featured on this page.

Species that were neither referenced by name nor shown in any capacity on Prehistoric Planet will also not appear here. One example is Zuul crurivastator, which showed evidence of intraspecific combat between ankylosaurs in a 2022 study that was most likely referenced by the end of the Uncovered segment "How Did Ankylosaurs Use Their Tail?",[1] but since it was neither displayed nor referenced by name, it would not be present on this page.

It is best not to identify animals that cannot possibly or reasonably be identified (e.g. the mammals that appeared in "What Else Lived Alongside The Dinosaurs?"). If unidentified animals appear in a group (like the aforementioned mammals), they are to be put under one section. It is only once an animal can be reasonably identified that it can be given its own section.

Flamboyant Flyers[]

Dawndraco[]

Artwork of Dawndraco kanzai by the American Natural History Museum, used in "Flamboyant Flyers"

Dawndraco[PhP 1] (Dawn Dragon) is a pteranodontid pterosaur with a 6-meter (20-foot) wingspan. It lived in the Smoky Hill Chalk Member of the Niobrara Formation, Utica, Kansas, USA, around 86 million years ago, during the Santonian stage of the Late Cretaceous Period.

In 2017, Dr. Elizabeth Martin-Silverstone, one of the experts involved in Flamboyant Flyers" and other parts of Prehistoric Planet, along with other paleontologists, came to the conclusion that, based on the rostrum of Dawndraco specimen UALVP 24238, D. kanzai is merely a Pteranodon sternbergi (with UALVP 24238 in particular being one that has not yet reached skeletal maturity). The long, more shallowly tapering beak of UALVP 24238 shows that it is a male Pteranodon (which are larger than the females when fully grown), with its other supposedly unique features like its small, upwards-directed crest failing to convince the authors of the paper that it is distinct. Their conclusion is that, as odd as it may appear to be, Dawndraco is nothing more but a junior synonym of Geosternbergia (a pterosaur that possesses a similar, upwards-directed bulbous crest), which they, in turn, consider to just be a species of Pteranodon (P. sternbergi).[LMS 1] This debate is still not over, as Brazilian paleontologist Alexander W. A. Kellner submitted a rebuttal that same year, bringing up the idea that Dawndraco may have actually been more distinct than first thought, as, according to him, contrary to what has been said, UALVP 24238 has actually reached osteological maturity, pointing out that Martin-Silverstone et al. have acknowledged in their very paper that Dawndraco had several fused bones. He also further states that the skull's crushed condition did not prevent sutures from being identified (with the idea being that the sutures are gone because the bones are already fused), and that, while some bones bore pitting that supposedly indicated incomplete ossification, other bones did not. Overall, Dr. Kellner acknowledges that, while he believes that Dawndraco is valid and not a synonym of Pteranodon, it may take some time to actually establish the truth, not just for Dawndraco, but for other similar cases regarding pterosaurs either being distinct or one and the same as other species.[2]

Dawndraco kanzai, along with other crested pterosaurs, briefly appeared in the Uncovered segment "Flamboyant Flyers", which is dedicated to the extravagant displays of several pterosaur species.

Dsungaripterus[]

Artwork of Dsungaripterus weii by the American Natural History Museum, used in "Flamboyant Flyers"

Dsungaripterus[PhP 1] (Junggar Wing) is a dsungaripterid pterosaur that lived in the Tugulu Group, Junggar Basin, northwest China, around 133 - 100 million years ago, from the Hauterivian to the Albian stage of the Early Cretaceous Period. With a wingspan of 3.5 - 5 meters (11 - 16 feet), Dsungaripterus is believed to have navigated across the wetlands of the lacustrine (lake-based) Junggar Basin to probe mud, sand, and tiny crevices for food (e.g. shellfish), using the toothless, upturned tip of its narrow 50-centimeter (20-inch) skull to pry prey from cracks in rocks before crushing them with flat, knob-like teeth in the back of its jaws. According to a 2021 study, a Dsungaripterus with a body mass of around 4.2 kilograms (9.3 pounds) can exert a bite force of 61 newtons or 6.4 kilograms (14 pounds) in the front of its jaws, and 87 newtons or 9.1 kilograms (20 pounds) at 70% of its jaw length.[RP 1] Dsungaripterus is also known for the low, bony crest that ran from the back of its head to half of its beak. It is by this low crest, toothless, upturned beak tip, and knobbly rear teeth adapted for durophagy (the consumption of tough food, like shelled prey) that Dsungaripterus can be identified.

Dsungaripterus weii (depicted crushing a clam with its rear teeth), along with other crested pterosaurs, briefly appeared in the Uncovered segment "Flamboyant Flyers", which is dedicated to the extravagant displays of several pterosaur species.

Pteranodon[]

Artwork of Pteranodon longiceps by the American Natural History Museum, used in "Flamboyant Flyers"
“ Pteranodon. A genus of pterosaur that included some of the largest known flying reptiles, with wingspans over 7 meters. ”

Flamboyant Flyers

Pteranodon (Wing without Teeth) is one of the most famous of the pterosaurs, with over 1,200 discovered specimens found in Kansas, Nebraska, Wyoming, South Dakota and Alabama, USA, indicating its importance to the ecosystem of the Western Interior Seaway around 86 - 84 million years ago, during the Santonian stage of the Late Cretaceous Period.

Believed to play a role analogous to a modern-day seabird, with long, soaring wings and a diet comprised of fish and invertebrates (captured either by skimming the water's surface or, more likely, by diving and swimming), Pteranodon is also theorized to be sexually dimorphic, with the females possessing wingspans of 3.5 meters (11 feet) and the males possessing wingspans of 6 - 7 meters (20 - 23 feet), though estimates of 7 meters and above have proven to be unreliable in recent years.[MW 1] According to a 2021 study, a Pteranodon with a body mass of around 15.2 kilograms (33.5 pounds) can exert a bite force of 22.7 newtons or 2.3 kilograms (5.1 pounds) in the front of its jaws, and 32.4 newtons or 3.3 kilograms (7.3 pounds) at 70% of its jaw length.[RP 1]

Pteranodon longiceps, along with other crested pterosaurs, is shown in the Uncovered segment "Flamboyant Flyers", which is dedicated to the extravagant displays of several pterosaur species. It was first seen along with the heads of other pterosaurs like Thalassodromeus and Dsungaripterus, then it is put alongside Tupandactylus to briefly compare the two and further showcase the great variation of crest design in pterosaurs.

Raeticodactylus[]

Artwork of Raeticodactylus filisurensis by the American Natural History Museum, used in "Flamboyant Flyers"

Raeticodactylus[PhP 1] (Raetian Finger) is a non-pterydactyloid pterosaur that lived in the Kössen Formation of the central Austroalpine of Grisons, Switzerland, around 213 - 209 million years ago, from the Norian to the Rhaetian stage of the Late Triassic Period. It was named after the area it was found in, the Swiss Canton Grisons, which used to be known as "Raetia" (sometimes spelled as "Rhaetia") when it was a province under the Roman Empire, which promptly named the area after the confederation of Alpine natives who lived there, the Raeti. The actual etymology of "Raetia" is unknown, but some Roman historians like Justin and Pliny the Elder say that the Raeti either named themselves after Raetus, one of their leaders, or, more likely, after the Celtic term "rait", which means "mountain land".[3] Depending on which of the two proposed origins of the name is correct, the true meaning of the name "Raeticodactylus" would either be "Raetus Finger" or "Mountain Land Finger".

Being one of the earliest pterosaurs, it had a mere wingspan of 1.35 meters (4 feet, 5 inches),[4] and, based on other early pterosaurs like its relative Caviramus, evolved its fang-like teeth for an omnivorous diet (it was originally speculated to be a skim-feeding piscivore, a fish eater, prior to studies showing that pterosaurs did not have the anatomical and energy requirements necessary for skim-feeding),[MW 2][5] an idea reflected in "Could Giant Pterosaurs Really Hunt on the Ground?" It had a keel under its lower jaw as well as a thin, tall, bony crest on its nose, one of the first known head ornaments on a pterosaur.

Raeticodactylus filisurensis, along with other crested pterosaurs, briefly appeared in the Uncovered segment "Flamboyant Flyers", which is dedicated to the extravagant displays of several pterosaur species.

Sinopterus[]

Artwork of Sinopterus dongi by the American Natural History Museum, used in "Flamboyant Flyers"

Sinopterus[PhP 1] (Chinese Wing) is a sinopterine tapejarid pterosaur that lived in the Jiufotang Formation, Chaoyang, Liaoning, northeast China, around 120 million years ago, during the Aptian stage of the Early Cretaceous Period. It was the first tapejarid discovered outside of Brazil, as well as the earliest and most complete tapejarid.[6] It is a small animal with a maximum wingspan of 1.9 meters (6 feet, 2 inches) and weighed around 2.87 kilograms (6.3 pounds).[WMSN 1]

Sinopterus dongi is known from several different fossils of various growth stages. Other tapejaramorph pterosaurs that lived alongside it, like Huaxiapterus jii and Nemicolopterus crypticus, are believed to be merely juveniles of this species. Although Nemicolopterus has underwent ossification (bone formation) in its toes, sternum, and gastralia (belly ribs), making it appear to be a still-growing sub-adult, Dr. Darren Naish, Prehistoric Planet's lead consultant, along with Dr. Mark Witton and Dr Elizabeth Martin-Silverstone (both of whom were also involved in the making of the series), brought up how pterosaurs may have been precocial (mobile just shortly after birth and quick to mature, an idea shown on Prehistoric Planet through the Alcione and the azhdarchids of the Songliao Basin), thus, the fact that Nemicolopterus was undergoing some bone fusion and ossification at the time of its death does not necessarily dismiss the theory that it is just the hatchling of a Sinopterus,[DN 1] with the idea being formally presented and supported in a 2021 study.[WMSN 1]

Sinopterus dongi, along with other crested pterosaurs, briefly appeared in the Uncovered segment "Flamboyant Flyers", which is dedicated to the extravagant displays of several pterosaur species.

Tapejara[]

Artwork of Tapejara wellnhoferi by the American Natural History Museum, used in "Flamboyant Flyers"

Tapejara[PhP 1] (from a Tupi word meaning "Lord of Ways") is a pterosaur that lived in the Romualdo Formation, Santana Group, Araripe Basin, northeast Brazil, around 112 million years ago, during the Albian stage of the Early Cretaceous Period. It is the type species of the tapejarids, a family of pterosaurs known for their large crests. It was a small animal, with a wingspan of 1.2 - 1.3 meters (4 feet - 4 feet, 4 inches),[7] and a moderately-sized crest on its nose (though the animal is sometimes reconstructed with this crest being significantly taller and wider, extending all the way to the back of its head). Based off of its sclerotic rings (the bony rings within the eyes), which were proportionally moderate in size compared to those of modern birds and reptiles, Tapejara is suggested to have been cathemeral, active through both day and night in short, irregular intervals.[8] The animal was likely an omnivore or a frugivore (fruit eater) based on its parrot-like beak (which had a keel under its lower jaw), a trait shared by many of its relatives. According to a 2021 study, a Tapejara wellnhoferi with a body mass of around 2.23 kilograms (5 pounds) can exert a bite force of 8.7 newtons or 910 grams (2 pounds) in the front of its jaws, and 12.4 newtons or 1.3 kilograms (2.8 pounds) at 70% of its jaw length, supporting the idea that it is a frugivore or a nucivore (nut eater).[RP 1]

Tapejara wellnhoferi, along with other crested pterosaurs, briefly appeared in the Uncovered segment "Flamboyant Flyers", which is dedicated to the extravagant displays of several pterosaur species.

Thalassodromeus[]

Artwork of Thalassodromeus sethi by the American Natural History Museum, used in "Flamboyant Flyers"

Thalassodromeus[PhP 1] (Sea Runner) is a raptorial, macropredatory thalassodromine tapejarid (or thalassodromid azhdarchoid) pterosaur that lived in the Romualdo Formation, Santana Group, Araripe Basin, northeast Brazil, around 110 million years ago, during the Albian stage of the Early Cretaceous Period. It stood around 1.8 meters (6 feet) tall, matching a human in height, and has a wingspan of around 4.2 - 4.5 meters (14 - 15 feet).[9] According to a 2018 study, Thalassodromeus can open its mouth up to 50 degrees, close to the inferred 52-degree maximum gape of Quetzalcoatlus.[RP 2] Additionally, a 2021 study suggests that a Thalassodromeus with a body mass of around 33 kilograms (73 pounds) is capable of exerting a bite force of 157.22 newtons or 16 kilograms (35.3 pounds) in the front of its jaws, and 225 newtons or 23.13 kilograms (51 pounds) at 70% of its jaw length, several times more powerful than the bite forces of other pterosaurs its size.[RP 1]

Originally thought to be a skimmer like modern seabirds (hence its name), it is now believed to not possess the proper adaptations for such a lifestyle, for its scissor-like bill and thin crest would not have withstood the high and unstable forces of skimming (in fact, this resulted in an aluminum model of Thalassodromeus getting destroyed in an experiment meant to test its skimming capabilities), and the metabolic energy required for skim-feeding would not have been feasibly attained - much less sustained - by pterosaurs weighing over a kilogram (2.2 pounds),[MW 2][5] an idea brought up in "Could Giant Pterosaurs Really Hunt on the Ground?" Instead, it would have prowled inland environments with its short, broad wings (as opposed to the long, narrow wings of marine soarers) that are unlikely to get snagged on obstacles, and maneuvered quickly on the ground with long strides (helped by large shoulder muscles that permitted quick acceleration and short, compact feet). As a macropredator, it was adapted to hunt large prey in proportion to its size, capable of engaging in raptorial (grabbing) behavior by capturing struggling animals with its large, reinforced beak, subduing or outright killing them with the tremendous bite force generated by its powerful jaw muscles, before easily swallowing them with its large, concave palate.[MW 3] Having lived a few million years prior to the first azhdarchids, Thalassodromeus may be considered one of the most powerful predatory pterosaurs of its time. Alternatively, it has been suggested that Thalassodromeus is possibly a durophage (a consumer of hard-shelled prey) like Dsungaripterus, using its beak to probe and pry hard-shelled prey like mollusks from rocks before crushing them with its powerful bite force.[RP 1]

With a skull length of 1.42 meters (4 feet, 8 inches),[9] Thalassodromeus sethi is also known for having one of the largest known heads of any non-azhdarchid pterosaur, as well as one of the largest (in terms of proportion) head crests of any vertebrate. This thin, blade-like skull ornament resembles the double-plumed crown supposedly worn by Set (sometimes spelled as "Sutekh" or "Seth"), the Egyptian god of deserts, storms, violence, disorder, and foreigners (hence its species name, "sethi"), though it has been pointed out since 2005 that such a crown is actually worn by Amun, Egyptian god of air (later combined with the Egyptian sun god, Ra, under the name "Amun-Ra"). The crest is believed to have developed late in life (the specimen's fused bones indicated that it was an adult), and thus evolved for sexual display reasons rather than aerodynamics. It is by this distinctive, double-plumed blade-like crest and large skull that Thalassodromeus can be identified (it has been theorized that the V-shaped notch at the end of the crest was simply the result of damage chipping its tip off and that, in perfect condition, the crest had a more conventional convex shape much like its relative Tupuxuara, though this proposition did not garner that much support).

Thalassodromeus sethi, along with other crested pterosaurs, briefly appeared in the Uncovered segment "Flamboyant Flyers", which is dedicated to the extravagant displays of several pterosaur species.

Tupandactylus[]

Artwork of Tupandactylus imperator by the American Natural History Museum, used in "Flamboyant Flyers"
“ Tupandactylus imperator. Known from four nearly complete skulls, Tupandactylus is known for its large cranial crest, composed partly of bone and partly of soft tissue. ”

Flamboyant Flyers

Tupandactylus (Tupan Finger, named after the creator god - or, alternatively, the manifestation of a god in the form of lightning and thunder - of the Tupi people) is a tapejarid pterosaur that lived in the Crato Formation, Araripe Basin, northeast Brazil, around 112 million years ago, during the Albian stage of the Early Cretaceous Period. It is known for the two bony prongs poking from the tip of its snout and the back of its head, serving as the supports of a massive cranial crest of soft tissue, likely brightly colored to serve as a signaling device. The animal's lower jaw also has a keel under it, like Tapejara.

“ Some of the ideas that we've had are, in some way, it's helping the animal to fly, maybe it's reducing drag. We've done some tests in wind tunnels, and all the studies have found that there may be a very small advantage to it, and if there is a very small one, then what's the point of putting such a huge structure on the back of your skull if it's not really helping you? So yeah, it's got to be for something else. ”

Dr. Liz Martin-Silverstone, School of Earth Sciences, University of Bristol

The type species, Tupandactylus imperator, was shown in the Uncovered segment "Flamboyant Flyers", which is dedicated to the extravagant displays of several pterosaur species. It was first seen along with the heads of other pterosaurs like Thalassodromeus and Dsungaripterus, then it is put alongside Pteranodon to briefly compare the two and further showcase the great variation of crest design in pterosaurs. Tupandactylus was also shown later on in the segment in a graphic representation of a wind tunnel simulation meant to test the theory that pterosaur crests served an aerodynamic purpose. It was concluded that the advantage huge crests offered in flight was too small for it to be their primary purpose, with the structures being too big to be worth evolving for flight enhancement. With this, the theory that the crests were meant for display purposes appeared more acceptable, and indeed, it is believed that Tupandactylus and other crested pterosaurs were sexually dimorphic, with the males (mostly older ones) possessing larger body sizes than the females as well as larger crests (that is, if the females of the species possess crests of any sort at all).

Tupuxuara[]

Artwork of Tupuxuara leonardii by the American Natural History Museum, used in "Flamboyant Flyers"

Tupuxuara[PhP 1] (named after a "familiar spirit", a supernatural entity which assists and protects witches, in the mythology of the native Tupi people) is a thalassodromine tapejarid (or thalassodromid azhdarchoid) pterosaur that lived in the Romualdo Formation, Santana Group, Araripe Basin, northeast Brazil, around 112 million years ago, during the Albian stage of the Early Cretaceous Period. It stood around 1.8 meters (6 feet) tall, matching a human in height, and has a wingspan of around 4.7 meters (15 feet, 5 inches). According to a 2021 study, a Tupuxuara leonardii with a body mass of around 30.3 kilograms (67 pounds) is capable of exerting a bite force of 29.2 newtons or 3 kilograms (6.6 pounds) in the front of its jaws, and 42 newtons or 4.3 kilograms (9.5 pounds) at 70% of its jaw length.[RP 1] Originally viewed as a piscivore (fish eater) or frugivore (fruit eater), Tupuxuara is now believed to be a carnivore or omnivore competent in terrestrial locomotion, though, due to its lightly-built skull, it lacks the specializations that allowed its close relative Thalassodromeus to tackle and kill much larger prey. Based off of its sclerotic rings (the bony rings within the eyes), which were proportionally moderate in size compared to those of modern birds and reptiles, Tupuxuara is suggested to have been diurnal, active during daytime.[8]

There are three species of Tupuxuara, each with their own distinct crest shape. The type species, described in 1988, is T. longicristatus, which has a long, pointy, narrow crest that is swept back (hence its species name, "longicristatus", which means "long-crested"). Another species, named in 2009 by Dr. Mark Witton (a palaeontologist best known for his pterosaur research, and one of the many experts who worked on Prehistoric Planet), is T. deliradamus, which has a shorter, more rounded crest and a diamond-shaped opening in its skull (its species name, "deliradamus", means delirious and diamond, which references both its diamond-shaped skull opening and the song "Shine on You Crazy Diamond" by Pink Floyd, one of Dr. Witton's favorite bands).[MW 4] However, a 2023 study casts doubt on whether this species is Tupuxuara, as it instead appears to be a tapejarine related to Caupedactylus.[10] What appears to be the most recognized specimen, however, is a species discovered in 1994, Tupuxuara leonardii (named in honor of Italian sprinter Giuseppe Leonardi). Its crest appears broader than that of T. longicristatus, but longer, more angular, and not as rounded as that of T. deliradamus. Tupuxuara, like other pterosaurs, likely only fully grew its crest upon reaching sexual maturity, as a subadult specimen described in 2006 did not have a fully-developed crest.[MW 5]

Tupuxuara leonardii,[PhP 1] along with other crested pterosaurs, briefly appeared in the Uncovered segment "Flamboyant Flyers".

Did Velociraptor Have Feathers?[]

Several Maniraptorans[]

Several dinosaurs are confirmed or at least strongly implied to have feathers
“ The idea that dinosaurs like Velociraptor were fully feathered is no longer at all controversial. We currently know of about 60 dinosaur species that are completely covered in feathers just like modern birds. ”

Dr. Darren Naish, Lead Scientific Consultant

A total of 46 different maniraptorans (counting repetitions of the same animal) were shown in a single diagram in "Did Velociraptor Have Feathers?" Most of the species displayed were dromaeosaurs (at least one of which appears to be an unenlagiine, as indicated by its narrow snout) and troodontids, though there is at least one oviraptororosaur (the same specimen was shown twice in the diagram) and one therizinosaur (which was also shown twice in the diagram).

Zhenyuanlong[]

JPM-0008, the holotype specimen of Zhenyuanlong suni. Note the preserved traces of feathers on its arms and tail.
“ Some of the most perfect fossilized feathers have been discovered in China. This is an image of a specimen that was found in 2015. It's called "Zhenyuanlong". And you can probably guess from these huge claws on its feet that it was related to a Velociraptor. But also, you can see amazingly perfect detail of feathers down its tail and more on its arms, its wings. ”

David Attenborough, Did Velociraptor Have Feathers?

Zhenyuanlong (Zhenyuan's Dragon, named after Zhenyuan Sun, a representative of Jinzhou Paleontological Museum who secured the animal's remains for study) is a dromaeosaurid that lived in the Yixian Formation of Liaoning, China, around 125 million years ago, during the Aptian stage of the Early Cretaceous Period. It resembled Velociraptor in height and length, being around two meters (6 feet, 7 inches) long (though it should be noted that the animal's bones, still in the process of growing, indicate that it is a subadult), but appeared to have been slightly more robust, with a shorter but broader skull and the shortest arm-to-leg length ratio of any dromaeosaur except the basal dromaeosaur Mahakala and the large unenlagiine Austroraptor.

An image of the remains of JPM-0008, the Zhenyuanlong suni holotype specimen, was briefly given focus in the Uncovered segment "Did Velociraptor Have Feathers?". Its sickle toe claws were brought up to indicate its relation to Velociraptor, and it feathery coat, preserved in exquisite detail, was given emphasis to show clear evidence of the presence of feathers on dromaeosaurs.

Armed for Seduction?[]

Ceratosaurus[]

Coelophysis evolves into Ceratosaurus, which evolves into Carnotaurus
“ ... over millions of years, these dinosaurs came to rely more on their mouths for holding and killing prey, so their heads became more powerful, and their arms became smaller. ”

Dr. Darren Naish, Lead Scientific Consultant

Ceratosaurus (Horned Lizard) is a basal averostran theropod dinosaur that lived in the Morrison Formation of North America, the Lourinhã Formation of Portugal, and possibly the Tendaguru Formation of Tanzania, East Africa, and the Tacuarembó Formation of Uruguay, around 153 - 148 million years ago, from the Kimmeridgian to the Tithonian stage of the Late Jurassic Period.

Recognized for its three horns (one over each eye and one on its nose) and its four-fingered hands, this theropod, only 2 meters (6 feet, 7 inches) tall, 7 meters (23 feet) long,[GP 1] and around 452 - 980 kilograms (997 - 2,160 pounds) in weight,[GP 2][GP 1][11] is usually remembered as a mesopredator that was overshadowed by other, larger carnivores that coexisted with it, like Allosaurus, Torvosaurus (the last and largest of the megalosaurids), Saurophaganax (which may or may not be just an exceptionally-large Allosaurus), and Veterupristisaurus (the oldest known carcharodontosaurid). However, Ceratosaurus is still a fearsome predator in its own right, and may have avoided conflict (albeit not entirely so) by occupying a different niche. Its lower, slimmer, and more sinuous build may have permitted it to hunt in forests and other more restricted terrains while the other predators mostly hunted in more open areas. Ceratosaurus has a skull length of 60 centimeters (2 feet),[12] allowing the animal to exert a bite force of 2,432 newtons or 250 kilograms (550 pounds) in the front of its jaws, and 6,000 newtons or 612.4 kilograms (1350 pounds) in the back of its jaws.[13]

Ceratosaurus nasicornis was briefly shown in the Uncovered segment "Armed for Seduction?", being part of an evolutionary sequence where Coelophysis turns into Ceratosaurus, which then morphs into Carnotaurus (referencing how abelisaurs evolved from members of the ceratosaurian clade). Early theropods like Coelophysis relied on grabbing prey with long, narrow and weak snouts, long arms, and functional fingers with long claws. But as they continued to evolve, their heads become more powerful, and their arms grew smaller and less functional. While Ceratosaurus had functional but shorter arms, by the time of Carnotaurus, these limbs were almost useless, lacking claws and even wrists entirely, with the four fingers they got from their ceratosaurian ancestors even immobilized since they were fused together.

Coelophysis[]

Coelophysis as it appeared in "Armed for Seduction"
“ Everyone knows that T. rex had small arms. But dozens of predatory dinosaurs from all around the world had small arms too. They all evolved from earlier dinosaurs that had much longer arms... ”

Dr. Darren Naish, Lead Scientific Consultant

Coelophysis (Hollow Form, a reference to the animal's vertebrae) is an early theropod dinosaur that lived in southwestern USA around 228 - 201 million years ago, from the Carnian to Rhaetian stages of the Late Triassic Period. It grew to around over 1.2 meters (4 feet) tall, three meters (10 feet) long,[GP 2][14] with weight estimates ranging within 15 - 25 kilograms (33 - 55 pounds).[GP 1] The animal had an overall slender build, with a skull that is 27 centimeters (11 inches) long, able to exert a bite force of 72 newtons or 7.3 kilograms (16 pounds) in the front of its jaws, and 290 newtons or 30 kilograms (66 pounds) in the back of its jaws.[13]

As one of the earliest (but not the absolute earliest) theropods, Coelophysis can show just how theropods started out, and how they evolved into the more formidable hunters that appeared later down the Mesozoic Era. Based on its sclerotic rings (the bony rings that support its eyes), Coelophysis is a diurnal predator, possessing sharp vision on par with modern-day birds of prey like eagles and hawks, but possessing poor night vision.[15][16] Several Coelophysis are usually found grouped together in close proximity, which could either be an indication of pack-hunting behavior, or several animals simply being swept away by a flash flood. Coelophysis was also, at one point, believed to have cannibalized their own juveniles during times of hardship, but studies since then have indicated that the fossils just so happened to end up on top of each other, with the juveniles apparently being too large to have been consumed (be it whole or in chunks), the bones lacking tooth marks or stomach acid pitting, and the supposedly cannibalized individuals being found significantly lower than the larger animals.[17]

Coelophysis bauri was briefly shown in the Uncovered segment "Armed for Seduction?", being part of an evolutionary sequence where it turns into Ceratosaurus, which then morphs into Carnotaurus (referencing how abelisaurs evolved from members of the ceratosaurian clade). Early theropods like Coelophysis relied on grabbing prey with long, narrow and weak snouts, long arms, and functional fingers with long claws. But as they continued to evolve, their heads become more powerful, and their arms grew smaller and less functional.

Could Giant Pterosaurs Really Hunt on the Ground?[]

Haenamichnus[]

Haenamichnus, a set of azhdarchid footprints found in South Korea
“ An azhdarchid had no option. It must have landed to find food. But could it really walk fast enough to hunt? Scientists needed evidence to persuade them that it could do anything more than just waddle. That evidence comes from 66 million year-old footprints. ”

David Attenborough, Could Giant Pterosaurs Really Hunt on the Ground?

Haenamichnus (Haenam Track) is a set of tracks attributed to an azhdarchid pterosaur in the Uhangri Formation of Haenam County, South Jeolla Province, South Korea, 81 - 79 million years, during the Campanian stage of the Late Cretaceous Period.

The foot of an azhdarchid
“ The biggest pterosaur track in the world was made by a walking giant azhdarchid. That's not only a cool thing to have, it tells us an awful lot about how efficient they were at walking. ”

Dr. Mark Witton, Paleoartist & Paleontologist

Much like the Mongolian Titan, Haenamichnus is only known from footprints, with no fossil of the animal's actual body being found yet. Even so, these tracks, discovered in 2002,[18] are currently the largest pterosaur tracks ever discovered, and were likely left by an animal 3 meters (10 feet) in height, 10 meters (33 feet) in wingspan, and 145 kilograms (320 pounds) in body mass.[19]

Given their longer limbs, azhdarchids had strides superior to those of smaller pterosaurs
“ These tracks show they held their limbs directly under their body, giving them an upright stance. Their feet were padded, and unlike the small pterosaurs, their long legs gave them an enormous stride. ”

David Attenborough, Could Giant Pterosaurs Really Hunt on the Ground?

Although the animal that left the footprints remains undiscovered, the tracks themselves show that even the largest pterosaurs can comfortably walk on all fours. On land, the same wings that allowed azhdarchids to fly in the air can be used as light yet sturdy stilts that allow them to cover more distance with each step.

The Uncovered segment "Could Giant Pterosaurs Really Hunt on the Ground?" states that the tracks were made 66 million years ago, but this is likely an oversight, as the given location of the discovery on a map, a diagram of the footprints, and Dr. Mark Witton calling it "the biggest pterosaur track in the world" prove that this is meant to be Haenamichnus uhangriensis, an ichnotaxon left and preserved 81 - 79 million years ago. A second set of footprints from the Haman Formation of the South Gyeongsang Province in South Korea, dating to 105.4 million years ago during the Albian stage of the Early Cretaceous Period, was once interpreted as a second, older ichnospecies, Haenamichnus gainensis, though these are now interpreted as the archosaur ichnotaxon Batrachopus cf. grandis, either a bipedal crocodylomorph or a therizinosaur.[20][21]

What Else Lived Alongside The Dinosaurs?[]

Several Mammals[]

Seven unidentified mammals as they appeared in "What Else Lived Alongside The Dinosaurs?"
“ Despite people thinking that the Cretaceous was all about dinosaurs, there were tons of mammals. We find things that lived in the water, like beavers today. We see things that were running around in the trees and even gliding, and things that were living under the ground and digging into the soil. And you see mammals evolved a lot of characteristics related to being able to move around at night. ”

Anjali Goswami, Research Leader, Palaeobiology

A total of eight unidentified mammals (one displayed behind research leader Anjali Goswami, seven more in a revolving diagram) were shown in the Uncovered Segment "What Else Lived Alongside The Dinosaurs?" One of these mammals has outstretched patagia (wing membranes), meaning that it could be Volaticotherium, Maiopatagium, a cousin of theirs, or some other unrelated mammal that evolved wing membranes.

How Did Ankylosaurs Use Their Tail?[]

Ankylosaurus[]

Skeleton of an ankylosaur (titled Ankylosaurus on the bottom left) meant to stand in for Tarchia
“ Powerful muscles and reinforced bone allow them to use these structures as weapons. Fossils show ankylosaur tails had similar adaptations. ”

David Attenborough, How Did Ankylosaurs Use Their Tail?

Ankylosaurus (Fused Lizard) is the type species of the ankylosaurs, as well as the last member of the family. At around 2.14 meters (7 feet) tall, 8 meters (26 feet) long, and 8 metric tons (8.8 short tons) in mass, it was also likely the largest ankylosaur.[22] It lived in various regions of western North America (e.g. the Denver, Hell Creek, Lance, and Scollard Formations) 68 - 66 million years ago, during the Maastrichtian stage of the Late Cretaceous Period, making it one of the last non-avian dinosaurs, before the Cretaceous-Paleogene Extinction Event 66.043 million years ago,[23] a catastrophe that ultimately wiped out three-quarters of all life on Earth, including all non-avian dinosaurs.

Reconstruction of an ankylosaur (titled Ankylosaurus on the bottom left) meant to stand in for Tarchia

In a 2011 study that estimated the proportions of large-bodied dinosaurs in the Hell Creek Formation, it was revealed that Ankylosaurus made up only 1% of the dinosaurs found in Hell Creek, though many other dinosaurs (e.g. Pachycephalosaurus) were just as rare, if not even more so, with some not even included in the breakdown of Hell Creek's paleo-population.[24] However, several factors known as taphonomic biases can also affect these population estimates, making various species appear to be more or less common than they actually were during their time. Some of the most common sources of bias include an animal's physical traits, the characteristics and conditions of the organism's habitat (especially its final resting place), the accessibility of the fossils in question, and human errors.

The tail of Ankylosaurus, showing how reinforced an ankylosaurid's tail is, allowing it to deliver tremendous force when swung
“ There's evidence on the pelvis for muscles that extended down the tail, and that would have attached to the handle of this tail club. ”

Dr. Susannah Maidment, Natural History Museum

Ankylosaurus magniventris briefly appeared in the Uncovered segment "How Did Ankylosaurs Use Their Tail?". While one diagram near the end of the segment appeared to show Tarchia, a label on the bottom left of the skeleton (which is later filled in with skin) actually identified it as Ankylosaurus. This diagram demonstrated how ankylosaurs would have swung their tails, stiffened and reinforced by bony rods.

References[]

General[]

  1. Palaeopathological evidence for intraspecific combat in ankylosaurid dinosaurs
  2. Rebuttal of Martin-Silverstone et al. 2017, 'Reassessment of Dawndraco kanzai Kellner 2010 and reassignment of the type specimen to Pteranodon sternbergi Harksen, 1966'
  3. Raetia as explained in the Encyclopædia Britannica
  4. A new Triassic pterosaur from Switzerland (Central Austroalpine, Grisons), Raeticodactylus filisurensis gen. et sp. nov.
  5. 5.0 5.1 A new view of pterosaur feeding habits
  6. A new pterosaur (Pterodactyloidea, Tapejaridae) from the Early Cretaceous Jiufotang Formation of western Liaoning, China and its implications for biostratigraphy
  7. On the osteology of Tapejara wellnhoferi KELLNER 1989 and the first occurrence of a multiple specimen assemblage from the Santana Formation, Araripe Basin, NE-Brazil
  8. 8.0 8.1 Nocturnality in Dinosaurs Inferred from Scleral Ring and Orbit Morphology
  9. 9.0 9.1 The function of the cranial crest and jaws of a unique pterosaur from the Early Cretaceous of Brazil
  10. On the phylogenetic affinities of the tapejarid pterosaur ‘Tupuxuara deliradamus’ from the Lower Cretaceous of Brazil
  11. Foster, J. (2007). "Gargantuan to Minuscule: The Morrison Menagerie, Part II". Jurassic West: The Dinosaurs of the Morrison Formation and Their World. Indiana University Press
  12. Madsen, J.H.; Welles, S.P. (2000). Ceratosaurus (Dinosauria, Theropoda): A Revised Osteology. Utah Geological Survey
  13. 13.0 13.1 Estimating bite force in extinct dinosaurs using phylogenetically predicted physiological cross-sectional areas of jaw adductor muscles
  14. Geology and taphonomy of the Coelophysis quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico
  15. Rinehart, L.F.; Heckert, A.B.; Lucas, S.G.; Hunt, A.P. (2004). "The sclerotic ring of the Late Triassic theropod dinosaur Coelophysis". New Mexico Geological Society Spring Meeting. 26: 64.
  16. Rinehart, L.F.; Lucas, S.G.; Heckert, A.B.; Spielmann, J.A.; Celesky, M.D. (2009). "The paleobiology of Coelophysis bauri (Cope) from the Upper Triassic (Apachean) Whitaker quarry, New Mexico, with detailed analysis of a single quarry block". New Mexico Museum of Natural History & Science, A Division of the Department of Cultural Affairs Bulletin. 45: 260.
  17. Gay, R.J. (2010a). Notes on Early Mesozoic Theropods (First ed.). Lulu press. pp. 9–24.
  18. New pterosaur tracks (Pteraichnidae) from the Late Cretaceous Uhangri Formation, southwestern Korea
  19. Estimating body weight from footprints: Application to pterosaurs
  20. Trackway evidence for large bipedal crocodylomorphs from the Cretaceous of Korea
  21. The Plantigrade Segnosaurians: Sloth Dinosaurs or Bear Dinosaurs?
  22. Rates of Dinosaur Body Mass Evolution Indicate 170 Million Years of Sustained Ecological Innovation on the Avian Stem Lineage
  23. Dinosaur extinction battle flares
  24. Dinosaur Census Reveals Abundant Tyrannosaurus and Rare Ontogenetic Stages in the Upper Cretaceous Hell Creek Formation (Maastrichtian), Montana, USA

Dr. Darren Naish[]

Gregory Scott Paul[]

  1. 1.0 1.1 1.2 The Princeton Field Guide to Dinosaurs
  2. 2.0 2.1 Predatory dinosaurs of the world : a complete illustrated guide

Dr. Elizabeth Martin-Silverstone[]

Dr. Mark Witton[]

Dr. Mark Witton, Dr. Elizabeth Martin-Silverstone, and Dr. Darren Naish[]

Rodrigo Pêgas[]

Prehistoric Planet[]

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 As indicated by the American Natural History Museum, the original source of the pterosaur artworks used in Flamboyant Flyers, "Why Did Pterosaurs Have Crests?"
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