― David Attenborough, Ice Worlds
Present on Prehistoric Planet is an unnamed troodontid that lived somewhere in the Arctic Circle. It most likely resided in the Prince Creek Formation, Alaska, USA, 71 - 69 million years ago, during the Maastrichtian stage of the Late Cretaceous Period.
According to Dr. Darren Naish, Prehistoric Planet's lead consultant, the show originally considered calling it Troodon, Stenonychosaurus, or Latenivenatrix.[DN 1] Unfortunately, each name is associated with problems. The validity of Troodon has been called into question since 2011,[1] and the debate regarding that continues to this day. Latenivenatrix may be a junior synonym of Stenonychosaurus,[2] and even if it were distinct, as the largest known troodontid, Latenivenatrix has a 3.5-meter (11-foot) body length, twice that of this unnamed troodontid. Lastly, even if all three species were equally valid, they all lived in the Campanian stage of the Late Cretaceous, around 77 - 75 million years ago, at least 3 - 5 million years before the show's Maastrichtian time scope. Hence, it is understandable that the species ultimately went unnamed in the show.
Paleobiology[]
Size and Physique[]
While unlikely to be Stenonychosaurus due to the unnamed troodontid having lived further up north and later in time, Stenonychosaurus closely matches the features of this species, with a height of 1.2 meters (4 feet), a body length of 2.5 meters (8 feet, 3 inches), and a weight of 35 kilograms (77 pounds), making it slightly larger than this six-foot Alaskan troodontid.
It should be noted that Prince Creek is also home to still-unnamed troodontids that make up two-thirds of all theropod fossils in the area (as opposed to other areas like Montana, where troodontids only made up 6% of the native fauna). These troodontids are almost twice as big as their cousins in Alberta and Montana, equivalent to the size of Latenivenatrix.[3][4][5] However, since the Alaskan troodontids of Prehistoric Planet are stated to be only six feet in length, the show might not have intended it to be a portrayal of the large troodontid species (unless they are intended to be juvenile forms, though this is unlikely).
Nevertheless, like all troodontids, this unnamed species is slightly smaller and more gracile than its more robust relatives, the dromaeosaurs, with a smaller sickle claw that is not as significantly recurved.
Jaws and Dentition[]
The type species of the family of this unnamed animal, Troodon (Wounding Tooth), is named for prominent serrations on its teeth, with wear patterns indicating that their U-shaped jaws, weak compared to those of their relatively more robust cousins, the dromaeosaurs, were best suited for soft-bodied prey like early mammals.[6] However, there were also suggestions that these serrations actually resembled those seen on the teeth of herbivorous reptiles, leading to theories about troodontids being omnivores.[7]
Brain and Senses[]
― David Attenborough, Ice Worlds
As maniraptorans, troodontids are known for their large eyes which faced forward to provide powerful binocular vision and depth perception that works well even in low-light conditions (indicating a possible nocturnal or crepuscular lifestyle), enlarged middle ear cavities near the eardrums to detect low-frequency sounds, and large brains with high encephalization quotients, with intelligence comparable to those of modern-day flightless birds, suggesting that they engaged in complex behaviors that were advanced compared to those of other non-avian dinosaurs.[8][9] Some troodontids even possess an asymmetric ear arrangement like some strigiform birds (owls), with one ear higher than the other, allowing them to pinpoint sounds with more accuracy.[10] In summary, due to their keen senses and large brains, troodontids are often recognized as the smartest non-avian dinosaurs.
Prehistoric Planet's Portrayal[]
Prehistoric Planet depicts the Alaskan troodontid with mostly-gray plumage, with a black coloration covering the top of its head (save for white eyebrows) and wing feathers, and a whitish-gray underside and legs, providing the animal some countershading. It also possesses a pygostyle (tail fan), a bare gray snout, and black feathers on the back of its head, which occasionally flare out, similar to the ornamental head feathers of some modern birds.
Like Atrociraptor, Dromaeosaurus, and Imperobator, this Alaskan troodontid is depicted with legs that are heavily-feathered like those of a booted eagle, in contrast with other paravians in the series like Velociraptor, which have bare legs. This trait is likely an adaptation for the cold environment it lived in, or, conversely, the heat of the forest fires that frequently occur in the region during summer.
Paleoecology[]
Paleoenvironment[]
Main: Prince Creek Formation
Main: Prince Creek Formation
― David Attenborough, Ice Worlds
This troodontid is stated to live within the Arctic Circle. While it isn't the large troodontid of Alaska,[5] it is likely that it did live 71 - 69 million years ago in the Prince Creek Formation, a polar woodland that experienced 120 days of winter darkness, with temperatures dropping as low as 2 - 4 degrees Celsius (36 - 39 degrees Fahrenheit) during the cold months. Even so, the warm conditions of summertime are not devoid of danger, and may in fact start lightning storms and cause the area to suffer frequent forest fires.
Hunting Tactics and Feeding Preferences[]
― David Attenborough, Ice Worlds
Due to their large brains giving them high intelligence, troodontids may have used tactics similar to those of birds of prey today. Based on behaviors of modern-day lizards, birds, and even crocodilians, the troodontids using burning twigs as tools to deliberately spread fires to flush out prey in Ice Worlds may not be as far-fetched as it first appears.[DN 2]
Appearance[]
In the fourth segment of Ice Worlds, a lightning storm, formed by the warm summer conditions, sets a forest in the Arctic ablaze. One troodontid, slowly walking in the midst of the flames, tries to pinpoint the source of the sounds it hears, the calls of distress of other animals. It stalks around the forest, waiting for some of these other creatures to flee the flames and run straight into it. Eventually, the troodontid comes across a stick, smoking embers on its tip. Realizing what it can do with this, the troodontid runs off with the burning twig in its mouth, eventually dropping it by a tree that still seems unaffected by the flames.
With this action, the forest fire spreads, and several Cimolodons rush out of the woods, right where the troodontid is waiting to ambush and pursue them. The theropod eventually grabs one of the multituberculates with its jaws, pinning it to the ground while shaking its neck, snapping it in the process. Its hunt a success, the predator gets up, holding the limp body of its latest kill by the neck, shaking it one last time before letting loose a single chirp of satisfaction, slightly flaring out the feathers on the back of its head.
References[]
General[]
- ↑ A New Troodontid Theropod, Talos sampsoni gen. et sp. nov., from the Upper Cretaceous Western Interior Basin of North America
- ↑ Anatomical, morphometric, and stratigraphic analyses of theropod biodiversity in the Upper Cretaceous (Campanian) Dinosaur Park Formation
- ↑ On the Occurrence of Exceptionally Large Teeth of Troodon (Dinosauria: Saurischia) from the Late Cretaceous of Northern Alaska
- ↑ A Diminutive New Tyrannosaur from the Top of the World
- ↑ 5.0 5.1 The giant troodontid dinosaurs of Alaska
- ↑ Fiorillo, Anthony R. (2008) "On the Occurrence of Exceptionally Large Teeth of Troodon (Dinosauria: Saurischia) from the Late Cretaceous of Northern Alaska" Palaios volume 23 pp.322-328
- ↑ Holtz, Thomas R., Brinkman, Daniel L., Chandler, Christine L. (1998) Denticle Morphometrics and a Possibly Omnivorous Feeding Habit for the Theropod Dinosaur Troodon. Gaia number 15. December 1998. pp. 159-166.
- ↑ Cranial anatomy of Stenonychosaurus inequalis (Saurischia, Theropoda) and its bearing on the origin of birds
- ↑ A new troodontid (Theropoda: Troodontidae) from the Late Cretaceous of central China, and the radiation of Asian troodontids
- ↑ On the left-right asymmetry in dinosaurs
Dr. Darren Naish[]
- ↑ The names Troodon, Stenonychosaurus, and Latenivenatrix were considered for the Alaskan Troodontid, though it was ultimately referred to by just its group name on Prehistoric Planet.
- ↑ The concept of troodontids deliberately spreading fire is based on how modern-day predatory birds spread forest fires to flush out prey. While it is yet to be confirmed whether troodontids were similar to modern-day predatory birds in terms of cognitive abilities and behavioral flexibility, it is reasonable given the the surprisingly flexible and innovative ways of modern lizards, birds, and crocodilians.
Prehistoric Planet[]
- ↑ As stated in Ice Worlds.
Theropod Dinosaurs | |||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| |||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||
|
Theropod Dinosaurs | |
---|---|
Abelisauroids | |
Abelisaurids | |
Noasaurids | |
Maniraptoriforms (Non-Paravian) | |
Ornithomimosaurs | |
Others | |
Maniraptoriforms (Paravian) | |
Birds | |
Dromaeosaurids | Dromaeosaurines |
Velociraptorines | |
Unenlagiines | |
Others | |
Troodontids |
|
Tyrannosaurids | |
Tyrannosaurines |
Fauna by Area | |
---|---|
Africa | |
Madagascar | |
Morocco | |
America, North | |
Alberta, Canada |
Horseshoe Canyon Formation |
Scollard Formation | |
United States |
Hell Creek and Lance Formations |
Javelina Formation | |
Prince Creek Formation | |
Western Interior Seaway |
|
America, South | |
Argentina | |
Brazil | |
Others | |
Antarctica | |
López de Bertodano Formation |
|
Snow Hill Island Formation |
|
Asia | |
China | Nanxiong Formation |
Songliao Basin | |
India | |
Japan | |
Mongolia | Barun Goyot Formation |
Nemegt Formation | |
Russia | |
Europe | |
Hațeg Island |
|
Tethys Ocean |
|
Others | |
Oceania | |
New Zealand |
Fauna by Episode | |||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| |||||||||||||||||||||||
| |||||||||||||||||||||||
|