Troodon

*Troodon formosus*

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***“Troodon”*** (***Troödon*** in older sources) (Greek for "wounding tooth") is a dubious and former wastebasket taxon of relatively small avian-like dinosaurs known definitively from the Campanian age of the Cretaceous period (about 77 MYA). It includes at least one species, ***Troodon formosus***, is known from Alberta and Montana. Discovered in 1855, *T. formosus* was among the first dinosaurs found in North America, although it was thought to be a lizard until 1877. The genus name is Greek for "wounding tooth", referring to the teeth, which were different from those of most other theropods known at the time of their discovery. The teeth bear prominent, apically oriented serrations. These "wounding" serrations, however, are morphometrically more similar to those of herbivorous reptiles, and suggest a possibly omnivorous diet.

## Description

*“Troodon”* was about 2 meters (7 feet) tall and 40 kilograms (90 LB). It is expected to have been able to run at faster speeds with its light body-weight and powerful back legs. It had a long claw on the second toe and long clawed fingers, as suggested by other members in the family. "Troodon" teeth in Alaska show that Alaskan "Troodons" could grow up to be 4 meters (13 feet), some scientists suggest that these teeth represent a new genus of Troodontid. Despite being very well known, the teeth have not been described properly.

## Discovery

The “Troodon” tooth was originally classified as a "lacertilian" (lizard) by Leidy, but reassigned as a megalosaurid dinosaur by Nopcsa in 1901 (Megalosauridae having historically been a wastebasket taxon for most carnivorous dinosaurs). In 1924, Gilmore suggested that the tooth belonged to the herbivorous pachycephalosaur Stegoceras, and that Stegoceras was in fact a junior synonym of “Troodon” (the similarity of troodontid teeth to those of herbivorous dinosaurs continues to lead many paleontologists to believe that these animals were omnivores). The classification of Troodon as a pachycephalosaur was followed for many years, during which the family Pachycephalosauridae was known as Troodontidae. In 1945, Charles Mortram Sternberg rejected the possibility that Troodon was a pachycephalosaur due to its stronger similarity to the teeth of other carnivorous dinosaurs. With Troodon now classified as a theropod, the family Troodontidae could no longer be used for the dome-headed dinosaurs, so Sternberg named a new family for them, Pachycephalosauridae.

Scientists at a British university later conducted a thought experiment related to the evolution of “*Troodon,”* had it not been so brutally wiped out by the cataclysmic meteorite impact of 65 million years ago. The scientists discovered that, as “*Troodon's”* eyes grew, his head would have to frequently bend upwards to gain a better view.

The only way to solve that problem was to change the angle at which the spine was to the ground, in other words, to become erect. With “*Troodon”* standing upright, there would be no need for a tail to act as a counterbalance, henceforth reducing the requirement for a tail.

*“Troodon”* had become humanoid. Although this is just a thought experiment, it really does give a fascinating glimpse of what evolutionary paths certain lineages of dinosaur may have taken to, had they not been eradicated. This little carnivore was a relative of *Saurornithoides*, another type of Troodontid.

Before having much of the material reassigned, "Troodon" was a wastebasket for most Troodontids. It was only around 2017 when material began to be considered distinguishable enough to be reassigned as other genus. In many older papers, books, and articles, Troodontids are referred to as "Troodon" due to such.

## Habitats

“Troodons” lived in many different environments from woods, to forests, tundras, fields, meadows, grasslands, plains and lowlands. Like Coyotes, the "Troodon" was a likely very adaptable dinosaur that could survive in different habitats, as suggested by the remains of its relatives. This dinosaur has had presumed material found in Alaska, Alberta, Montana, Wyoming, Texas and New Mexico, though it is still unknown how much of this material belonged to "Troodon."

## JPInstitute.com Description

Troodon may have been the smartest of all the dinosaurs.

It had a very large brain when compared to its overall body size, which would have given it huge hunting advantage. It also had large eyes, long legs for speedy pursuit of prey, and sharp teeth.

Troodon is one of the most well known dinosaurs, with over 20 known specimens, including an egg with a Troodon embryo inside. It was actually one of the first North American dinosaurs to be named, originally described in 1856. However, the fragmentary remains were attributed to a number of dinosaurs before the original genus became accepted. It wasn't until Dr. Dale Russell described a fairly complete specimen that the pieces fell into place.

Troodon is also used as evidence in the bird/dinosaur debate, as it shares a number of common characteristics with birds.

## Dinosaur Field Guide Description

Troodon ("wounding tooth") is a small bird-like theropod. It has very long legs with specialized feet, in which the middle long bone was pinched out at the top to form a shock-absorbing wedge. This allowed it to run very fast. Troodon had very large eyes that faced mostly forward, so that could focus better. It is famous for having one of the largest brains (for its body size) of any dinosaur. Troodon had a jaw full of many small teeth, but they were not like the teeth of typical meat-eaters. Instead of little serrations running up and down the back of the teeth (as in most meat-eaters), there were much bigger bumps running along the side, as in many plant-eating dinosaurs and lizards. Some paleontologists speculate that Troodon may have eaten not only small mammals, lizards, and baby dinosaurs, but also insects, eggs, and even plants. Paleontologist Dave Varricchio discovered the first Troodon nests. Like oviraptorosaurs and ground-dwelling birds, Troodon would make a nest on the ground. It would then curl up on top of the nest to brood its eggs.

### Fun Facts

When the first Troodon tooth was found, paleontologists thought it was from a lizard!

### Trivia

Paleontologist Dale Russell once made a model of what he thought a modern, intelligent, tool-using descendant of Troodon would look like. He named this creature "dinosauroid."

## Appearance in other media

### *Jurassic Park*

* *Troodon* is mentioned in The Lost World novel. John Roxton discovered what he believed to be a *Velociraptor* skeleton in Mongolia. However, it was actually a *Troodon* skeleton (even though the *Troodon* genus is only found in North America, although there are troodontids in Asia). The fossil discovered had impressions of its skin.
* *Troodon* is one of the available dinosaurs on the IOS application, Jurassic Park Builder. The *Troodon* uses the same animations of *Compsognathus* and *Velociraptor*.
* *Troodon* was added to Jurassic World: The Game on January 4, 2016, but is a limited tournament dinosaur. It is a legendary carnivore. While it is accurately portrayed with a coat of feathers, it is shown inaccurately to be able to pronate it's hands.
* A pack of *Troodons* can be seen in Jurassic Park: The Game at the beginning and in other parts of the game. They are said to be venomous in the game, which is very unlikely. It is important to note that the species of *Troodon* in the game is the fictional species "*Troodon pectinodon*" (the name is combined with the genus *Pectinodon* for the species name) and not an existing species. The *Troodons* in the game, even though claimed to be created only using *Troodon* DNA, but still have pronated wrists and minimal quill-like feathers.
* *Troodon* was added to Jurassic World: Evolution on November 20 2018. It will inaccurately have a poisonous bite, much like Jurassic Park: The Game. It is also lacked the feathers which in real life they have and made sounds of Compsognathus.

## Links

http://web.archive.org/web/20040606034106/http://www.jpinstitute.com/dinopedia/dinocards/dc\_trood.html

## References

1. ↑ Holtz, Thomas R., Brinkman, Daniel L., Chandler, Chistine L. (1998) Denticle Morphometrics and a Possibly Omnivorous Feeding Habit for the Theropod Dinosaur Troodon. Gaia number 15. December 1998. pp. 159-166.
2. ↑ Template:Cite journal