Indominus rex (S/F)

Front view of a subadult female Indominus rex.

Indominus rex is a very large transgenic hybrid avetheropod dinosaur created by Dr. Henry Wu in 2012 and named by International Genetic Technologies. It was intended to be one of the upcoming attractions in Jurassic World on Isla Nublar. Its name means “fierce” or “untamable king,” and the name was intended to be scary and yet easy for children to pronounce. On the park website, the animal carries a danger rating of “Very High.” It was due to be displayed in the theme park in May 2015, but the actual date at which it would be put on display changed multiple times due to management issues stemming from its unpredictable nature.

Computer modeling of Indominus rex

According to the mobile game Jurassic World Alive, this genus (along with its descendant Indoraptor) are classified in the family Chimeridae. It should be noted that this family is fictional, and should not be confused with the factual family Chimaeridae. It cannot be reliably placed on the tree of life since it is a combination of many different species, but it is usually considered an avetheropod (including its tyrannoraptoran, abelisaurid, and carcharodontosaurid donors). It could be more broadly considered to be an archosaur (including its crocodilian genes), a saurian (including its snake genes), a tetrapod (including its frog and unidentified genes), or most generally a nephrozoan (including its cuttlefish genes).

Indominus rex was the most advanced hybrid genus engineered at the time. Its genome was constructed by inserting genes from various species into a template. Most of its constituent sources have been disclosed:

Official chart created to show the composition of the Indominus rex.
  • Tyrannosaurus rex: The genome of this animal was used as a template into which genes could be inserted. This was the only constituent part on public record, though the Jurassic World website identifies several abelisaurs and one carcharodontosaur which were also used in creating the genome.
  • Velociraptor antirrhopus: Genes from InGen’s Velociraptor were used to control development of the animal’s brain. This gave it heightened cognitive abilities and an instinctual comprehension of Velociraptor vocalizations, though this second effect may have been unintentional. Quills on the animal may have come from Velociraptor structural genes, but there is no confirmation of this.
  • Carnotaurus sastrei: Structural genes from this abelisaur were inserted into the Indominus genome in order to facilitate the development of supraorbital horns and thick scales on the body. Some of the vocalizations produced by Indominus are similar enough to those of Carnotaurus to facilitate rudimentary communication, suggesting that its vocal organs and communication-processing parts of its brain may also be influenced by genes from this abelisaur.
  • Pycnonemosaurus nevesi: Structural genes from this abelisaur were inserted into the Indominus genome in order to facilitate the development of supraorbital horns and thick scales on the body.
  • Quilmesaurus curriei: Structural genes from this abelisaur were inserted into the Indominus genome in order to facilitate the development of supraorbital horns and thick scales on the body.
  • Viavenator exxoni: Structural genes from this abelisaur were inserted into the Indominus genome in order to facilitate the development of supraorbital horns and thick scales on the body.
  • Majungasaurus crenatissimus: Structural genes from this abelisaur were inserted into the Indominus genome in order to facilitate the development of supraorbital horns and thick scales on the body.
  • Rugops primus: Structural genes from this abelisaur were inserted into the Indominus genome in order to facilitate the development of supraorbital horns and thick scales on the body.
  • Giganotosaurus carolinii: Structural genes from this carcharodontosaur were inserted into the Indominus genome in order to modify its bodily proportions and aid in the development of supraorbital processes. The exceptional size of the resultant animal may have been related to regulatory genes from this species.
  • Therizinosaurus cheloniformis: Structural genes from this therizinosaur were inserted into the Indominus genome in order to facilitate the development of lengthy and powerful front limbs, including large talons on the digits of these limbs.
  • Deinosuchus rugosus: Structural genes from this alligatoroid were inserted into the Indominus genome to adjust the morphology of its dentition. This resulted in a total of 74 teeth with a combination of theropod and alligatoroid features; its teeth measure an average of 25 centimeters (9.8 inches).
  • Sepiida: An unknown species of cuttlefish was sourced to allow the Indominus to survive an expedited growth rate. Genes from the cuttlefish controlling the development of chromatophores also integrated into the Indominus genome, resulting in an animal capable of advanced camouflage. Whether this was intentional on the part of its creators is unknown, but a holographic display featured in 2018 does detail its camouflage ability. According to Jurassic World: Evolution, the species of cuttlefish utilized for this purpose was Sepia officinalis, the European common cuttlefish.
  • Neobatrachia: An unknown species of tree frog was sourced for genes to allow the Indominus to modulate its infrared output, which was intended to help it survive in a tropical climate. This also enabled it to avoid detection by hiding its thermal signature from surveillance, a behavior which it could utilize due to its ability to detect its own infrared radiation. The icon used on the official chart is the outline of Agalychnis callidryas, the red-eyed tree frog, but whether this is the actual species sourced has not been confirmed.
  • Crotalinae: An unknown species of pit viper was sourced for genes to develop organs used for detecting infrared radiation. The Indominus possesses cranial cavities similar to the loreal fossae used by pit vipers. When combined with the ability to modulate its own thermal output, the Indominus could easily determine when it had successfully hidden itself from thermal sensing security devices. It is unlikely that this specific behavior was intended by Dr. Henry Wu, based on his surprised reaction. Genes from Crotalinae species may also have resulted in the ability to distend the jaw to an angle greater than ninety degrees by facilitating the development of highly kinetic quadrate and squamosal joints found in some snakes. The official chart refers to the snake as a “pit adder,” which is not a specific species. Rather, various types of snakes (mostly in the family Viperidae) are referred to as adders.
  • Tetrapoda: Structural genes were sourced from a species which is still undisclosed in order to facilitate the development of opposable thumbs in the Indominus. The only known animals with true opposable thumbs include various species of mammals, particularly primates, certain darwinopteran pterosaurs, and the frog genus Phyllomedusa. Other animals, such as chameleons and some theropod dinosaurs, have partially-opposable thumbs.
Close-up view of the left eye of an Indominus rex

Indominus rex displays features from a wide range of animals, due to the structural genes sourced from many different species. Its head clearly shows influence from abelisaurid and carcharodontosaurid species, with its small, conical supraorbital horns and decorative scales in particular coming from its abelisaurid heritage. The skull shape is determined by the tyrannosaur and carcharodontosaur genes in its genome; the teeth, of which there are 74, are conical in appearance due to the inclusion of alligatoroid DNA. The subadult in 2015 displayed a number of damaged or broken teeth jutting out at various angles. Its teeth measure 25 centimeters (9.8 inches) on average, and are continuously replaced throughout its life as with most theropods. There appear to be more teeth in the lower jaw than the upper jaw, and the teeth at the front of the lower jaw tend to jut outward and create a basket-like appearance of the lower jaw. The jaws are long and relatively narrow, capable of distending to a very wide angle in a manner similar to snakes. Like the alligatoroids from which its tooth development is derived, it lacks lips, differentiating it from most naturally-occurring nonavian theropods. On its face, the skin appears pulled tight, making the skeletal features plainly outlined; this includes cavities similar to the loreal fossae used by pit vipers to detect thermal radiation. Gray-colored quills appear on top of its head. The nostrils are quite large, similar to those of Tyrannosaurus, and the eyes are forward-facing with orange sclerae and black slit pupils similar to those of most Velociraptor subspecies. To protect its eyes, the Indominus has thick, transparent nictitating membranes which originate from the medial canthus of each eye. It has a comparatively short triangular pink tongue, which is not long enough to reach the lips.

Indominus rex demonstrates its distending jaws, with a clear view of the mouth interior. Also note the quadruped pose.

Rounded scales cover much of the animal’s body, giving it decent protection against most attacks. The larger scales are visible on the neck and back regions, but its scaly skin is quite thick everywhere, making the Indominus almost impenetrable. Its most noticeable anatomical feature, aside from its enormous jaws, are its forelimbs. Engineered with structural genes from Therizinosaurus, these arms are long enough to allow this animal to walk on four limbs or to crawl if it needs to. The hands are pronated, which is a common phenotypic error in all InGen’s theropods, but this feature actually benefits the Indominus as they enable it to get a grip on the ground. Each hand has four digits, including one opposable thumb and three much longer fingers. All four end in large talons. The arms are extremely muscular, and like the head, they bear long, gray-colored quills. However, its arms are less flexible than those of its predecessor Scorpios rex, as well as those of its descendant Indoraptor.

Detail on the right hand of an Indominus

The legs of Indominus are also very powerful, and end in three-toed feet which also have large talons on them. Unlike its genetic relatives, it lacks an enlarged raptorial toe claw. It is capable of running at thirty miles per hour when in a confined area. While it is a facultative quadruped, the Indominus walks bipedally when in a hurry, like Scorpios but unlike Indoraptor. Its tail is lengthy, but fairly nondescript. According to Dr. Henry Wu, the architect of the Indominus genome, the animal could reach fifty feet in length, making it the second-largest theropod known after Spinosaurus; however, his longest-lived specimen only survived until early adulthood and never reached its full size. A 2019 social media post by Universal Studios has given a 16.9-meter (55.4-foot) length for this animal, as well as a height of 6.7 meters (22 feet). Weight estimates are hard to come by, but at least one size chart suggests that it would reach 12,000 pounds (six U.S. short tons, or 5,443.1 kilograms) at full size. This would make the animal larger than, but lighter in weight than, a healthy mature female Tyrannosaurus rex.

Demonstration of metachrosis used for active camouflage in Indominus

Among some of the more spectacular features of the Indominus is its skin. While it typically rests at a white coloration, chromatophores in the skin of the animal allow it to perform metachrosis, changing the color of its body at will (excepting, of course, features such as its teeth or eyes). It appears to even have a layer of chromatophore-bearing tissue over its larger scales, enabling it to hide more efficiently. The chromatophores would be similar to those found in cuttlefish, as this is the genetic source of this feature in Indominus. Unlike in color-changing reptiles such as chameleons, which use cell signalling to enact physiological color change, cephalopods utilize a complex array of muscles to manually control the color expression of their chromatophore units. This would mean the muscular and nervous systems of Indominus are unlike those of any vertebrate. The individual chromatophore units consist of a single chromatophore cell surrounded by muscle, nerve, glial, and sheath cells. Within the chromatophore cell is the cytoelastic sacculus, an elastic sac containing granules of pigment. Muscular contraction can expand or contract the sacculus, compressing or spreading out the pigment granules and changing the cell’s reflectivity, translucency, and opacity. This causes the apparent color change.

Another of its abilities is infrared sensing. It accomplishes this using pit organs, similar to the loreal fossae of crotaline snakes (the “pit vipers”). These pits are located on top of the head, but are not easily distinguished as they are covered by a membrane. Behind the membrane is a deep air-filled pocket, and the membrane itself is highly vascularized and innervated. Terminal nerve masses of the trigerminal nerve form heat-sensitive receptors which relay information about the heat of the animal’s surroundings to the brain. It is able to visualize heat radiation at wavelengths between 5μm and 30μm. Resolution is low due to the small size of the pits; while Indominus is able to “see” heat, it does not use this ability to form full images. However, the optic tectum of the brain overlays both visual and thermal stimuli, giving the animal a combined set of information to interpret its world.

In addition, it is able to modulate its body’s infrared output. This mechanism originates from its tree frog genes, but as the Indominus is endothermic, it generates its own body heat. Frogs, on the other hands, are ectotherms and must use behavioral thermoregulation instead. Some tree frogs modify their body temperature by altering their skin color, since darker skin absorbs more heat while lighter skin repels it. The Indominus is capable of doing this, and could presumably use its chromatophores to alter its body temperature. However, it appears to have other physiological traits that allow it further control over its infrared output, which are poorly known (Dr. Henry Wu, its architect, was surprised to learn how advanced its control was, suggesting this was unintended). It is capable of reducing its body temperature to levels undetectable to thermal sensor technology, matching the background heat radiation of its environment. It knows that it has accomplished this by using its heat pits: by observing its own body, it can tell when its temperature has reached ambient levels.


The hatchling stage of Indominus rex is poorly known and few details have been disclosed. However, it is known that the claws are already fully-developed at the point of hatching, as they are used to break the eggshell. The skin appears to be slightly grayish and pinkish, but whether this is a fundamental feature or affected by the animal’s chromatophores is unknown. The eyes are disproportionately large for its skull size, which is normal in many baby animals, and there is no sign of horns or quills as in the mature animal. Body proportions, from what has been documented, appear similar to hatchling Velociraptor.

Hatching Indominus

Older juvenile or adolescent stages have not been observed. Fully-grown adults have also not been observed, due to the fact that neither specimen survived until adulthood; only the hatchling and subadult stages are known. However, Henry Wu’s confidence that the Indominus was ready for exhibition suggests that the adult and subadult differ in few ways other than sheer size.

Adulthood is reached in three or four years. According to InGen’s Senior Assets Manager Claire Dearing, this growth rate exceeded their expectations.

Sexual Dimorphism

Male Indominus have never been created. Thus, any sexual dimorphism is unknown.

Preferred Habitat

Due to its being artificially created, the preferred habitat of Indominus rex is unconfirmed. However, one in Jurassic World regularly favored forested areas after it escaped Paddock 11. There is no way to determine if this preference for forest was due to the habitat of its paddock, which was densely packed with trees, or because forest cover allowed it to camouflage more effectively.

Muertes Archipelago

There is no evidence that Indominus rex has been bred in the Muertes Archipelago, which was abandoned by InGen and Masrani Global during the time this species was created.

Isla Nublar
Indominus displaying aggressive jaw-gaping behavior

In 2012, two female I. rex were hatched in the Hammond Creation Laboratory after several years of design and engineering by Dr. Henry Wu. These would be the first and only members of their species bred on the island.

Sometime prior to 2014, the Indominus were moved to Paddock 11, a specialized holding facility located in the northwest region of Isla Nublar. They would remain here until their attraction was completed.

One of the two specimens was cannibalized by its sibling prior to November 2014.

The escaped Indominus near the south end of Sector 5, Isla Nublar (12/22/2015)

On December 22, 2015, the surviving Indominus escaped confinement due to a combination of corporate mismanagement and the secrecy and corruption surrounding the animal’s eventual purpose. The Indominus traveled southeast across the island, retreating north again after park security attempted to subdue it. Late that night, park staff collaborated in a complicated and highly risky plan to kill the animal, culminating in it being ambushed and killed by the park’s resident Mosasaurus. This incident resulted in the extinction of Indominus rex, and as the park was closed down and Henry Wu’s assets seized by the U.S. government very shortly after the incident, no more of this animal could be created.

Mantah Corp Island
Fresh subdermal tissue sample (including electronic tracking implant) from the left shoulder region of a nearly-mature Indominus

InGen’s rival, Mantah Corporation, was highly interested in the Indominus rex (which they had learned about from a corporate spy called Eddie, who worked with Dr. Wu). On December 20, 2015, they were able to acquire genomic data on the animal thanks to a second corporate spy named Sammy Gutierrez. All the while as InGen was operating Jurassic World, Mantah Corp was running their own facility in parallel on Mantah Corp Island. This facility was intended for research and testing of larger, more impressive de-extinct life for purposes that an animal rights champion like Simon Masrani would have never permitted at Jurassic World. Mantah Corp stole DNA samples from multiple InGen species and, eventually, learned how to perform de-extinction itself.

Despite having acquired the genomic data necessary to replicate Dr. Wu’s research, Mantah Corp is not believed to have yet followed through. As of June 2016 the facility had only two staff members, neither of whom were geneticists by trade, so the company may have been waiting for a skilled geneticist to be rotated in.

BioSyn Genetics Sanctuary

No Indominus rex have ever been reported outside the Gulf of Fernandez, though Henry Wu was eventually acquired by BioSyn in the early 2020s. He had, however, lost all his Indominus samples to government raids by then, and had struggled to continue his work. It is highly unlikely that BioSyn bred their own Indominus, but several of the hybrid’s donor species (such as Giganotosaurus, Therizinosaurus, Tyrannosaurus, and Velociraptor) were housed at the BioSyn Genetics Sanctuary as of 2022.

Black market

In early 2016, all Indominus genetic samples were confiscated by the U.S. federal government in a raid on lab facilities formerly used by Henry Wu and his colleagues at InGen. What has been done with them since is undisclosed. No assets belonging to this species have yet turned up on the global black market, but one can only imagine the astronomical prices even a sample of Indominus DNA would fetch. With this in mind, the United States government’s silence on the current status of the confiscated samples is concerning.

Wild populations

Indominus rex has, to the extent of current knowledge, only ever lived in the Gulf of Fernandez. InGen Security removed the remaining specimens from Dr. Wu’s laboratory during the 2015 incident, but much of his material (including all I. rex genetic material) was seized by the United States government shortly thereafter. What was eventually done with this genetic material, or what entity currently has control of it, is not known. No wild populations have ever been reported, which is all for the best.

Behavior and Ecology
Activity Patterns

Because it is an artificial creation, the activity patterns of Indominus rex are poorly researched. It has been known to be active at all times of day or night, though it was likely active primarily during the day when it was in captivity, as this is when its keepers would have brought it food.

Diet and Feeding Behavior

Indominus rex is a carnivore. Its natural diet is unknown, due to it being an artificial creation; only one was ever allowed into the wild, and it did not survive for a full day. While in captivity, it was fed prepared meat from cattle. In a deleted scene, Katashi Hamada explained that the animal could not be given live food, as this could lead to the animal only wanting live food from then on.

This species is not above cannibalism, as one of the two specimens killed and ate its sibling sometime after they hatched. The motivation for the attack is unknown, but it would have likely been the first instance of an Indominus killing and eating prey. However, there is no record of what caused this incident; the kill may have been due to territorial, rather than predatory, behavior. If this is the case, it is likely that Indominus would also eat the carcasses of territorial rivals it had killed.

InGen animal behaviorist Owen Grady investigates Indominus droppings, Isla Nublar (12/22/2015)

As soon as it was presented with the opportunity, however, the Indominus did take live food in the form of two InGen employees. Previously, it had nearly severed the arm of at least one handler during feeding time, indicating a strong desire to attack live prey even earlier than this. In a deleted scene, Owen Grady and Claire Dearing find a pile of dung which the junior novelization identifies as Indominus droppings, but it is not known what meal these droppings were from; at a minimum, it means that this animal digests its meals in an hour or two.

Once outside of containment, the animal was not seen to actively eat its victims, instead engaging in surplus killing. According to Owen Grady, these surplus killings were performed out of enjoyment rather than a predatory nature. Victims of the Indominus included several ACU personnel including Katashi Hamada, at least one Timack Construction employee, one Brachiosaurus, six Apatosaurus, one Ankylosaurus, and two Velociraptor. The animal also attempted to attack multiple Pteranodons in the Jurassic World Aviary, but failed to kill any. It ignored the smaller Dimorphodons. Its aim does not appear to be excellent, as it often misses bites aimed at small moving targets; the Indominus inherited the vertical slit pupils of Velociraptor, which are beneficial to animals that hunt low to the ground in long grass but are a hindrance in tall predators that attack from above. It is likely that the Indominus relies on senses other than vision to stalk and attack prey or other victims, such as its ability to detect infrared (heat) radiation.

The jaws of Indominus are capable of being distended to wrap around larger prey items.

The Indominus primarily uses its large jaws to kill prey and other victims, typically clamping smaller prey items around the midsection to instantly kill them. When facing larger targets than itself, this animal will bring its massive clawed arms into play, hooking its talons in to tear at exposed flesh or wildly swinging its arms around to create deep lacerations that lead to death by trauma and blood loss. It can also distend its jaws to wrap around larger victims. Its high intelligence allows it to be inventive in combat, learning new strategies and studying its victims to discern their weaknesses. For example, when combating an Ankylosaurus, the Indominus discovered that its jaws could not pierce the dorsal armor of its victim; it was able to use its claws to tear at the ankylosaur’s left rear leg, toppling the herbivore. The Indominus then pushed it onto its back, planted a foot on its victim’s belly, and bit into its neck to kill it.

Its jaws and teeth are powerful enough to puncture the aluminum oxynitride glass exterior of a gyrosphere, which was supposedly able to withstand a twenty-two caliber bullet. There is, however, strong evidence that the gyrosphere’s exterior was not as resilient as Masrani Global Corporation claimed it to be.

When handling smaller food items, the Indominus uses its hands to grasp its victims. It may then toss its victim to wound or kill it, or it may simply bite off chunks. Despite its enormous mouth, it usually does not swallow prey whole.

If prey items manage to escape, an Indominus may choose to wait in place to see if they accidentally reveal themselves again. The Indominus which had chased Zach and Gray Mitchell waited for roughly seventeen seconds after they escaped into a small pond, giving up when they did not resurface quickly enough.

Social Behavior

Only two of this animal were ever created, so the full extent of their social behaviors cannot be determined. At some point before the species was first hinted at in November 2014, one of the specimens had killed and cannibalized the other, leaving just one.

The game Jurassic World: Evolution also portrays the Indominus as a solitary animal which does not tolerate other members of its own species in its territory.

Indominus is, however, known to socialize with Velociraptor antirrhopus so long as the raptors behave in a subordinate manner. At the first sign of competition for dominance, the Indominus will attempt to kill its competitor.


No Indominus have ever reproduced naturally. The two which hatched in 2012 were documented at the time, however, and details of their hatching behavior is fairly well recorded. The incubation period is presumed to be between three and six months, based on the relatively small size of the hatchlings.

Indominus rex footprint. Prints of an adult human (left) to scale

Prior to hatching, the dinosaurs’ heartbeats were at around sixty beats per minute. Using its clawed hand, the hatchling broke through the upper part of the eggshell, pushing away shell fragments and tapping on the egg’s exterior in a nervous manner. It made a grasping motion with its hand, fingers visibly shaking. At this point, the heartbeats of both eggs began to speed up, suggesting that the sounds of the first hatchling were audible to the second and provoked a response. The second hatchling could be seen pushing its eggshell from the inside, failing to break it open immediately, while making a cooing sound. Meanwhile, the first hatchling cleared away enough eggshell to peer out of the egg. Its pupil was already extremely narrow, despite not having been exposed to any bright light before hatching. It could be heard making quiet hissing and growling noises. They received no assistance from their human caretakers during hatching, performing the act entirely on their own.

It is unknown how Indominus would go about mating and breeding, or if this artificial organism would be capable of reproduction at all. Both Tyrannosaurus and Velociraptor are portrayed with cloacae in Jurassic Park: The Game, so it is most likely that Indominus would have a cloaca to house its reproductive organs as well. Its genetic ancestor, Scorpios rex, is capable of producing fertile and genetically distinct offspring through parthenogenesis; this has not yet been confirmed in Indominus. According to the Jurassic Intel website, Indominus eggs are not particularly large, suggesting that the surviving female laid eggs during its time in Jurassic World, but it is unknown if any were fertilized. Most dinosaurs, including modern birds, lay unfertilized eggs after ovulation. Theropod eggs are generally oblong, and those belonging to a species of this size hatch after six months to a year.


The vocal sounds of the surviving Indominus were largely territorial in nature, as there were no other members of its species in existence following the death of one specimen via cannibalism. The volume of its roars have been measured at 140 to 160 decibels. It can be heard making snarling, growling, and roaring sounds more or less at random, but it makes particularly loud roars when it is about to start chasing a victim. It is known to pursue victims even when it is not hungry, so these vocalizations (which would be counterproductive if it were hunting for food) may be a means by which to make victims flee so that it can entertain itself chasing them. Similar behavior has been observed in Tyrannosaurus, which chases smaller animals as a form of play.

Some aspects of its physiology allow it to make noises similar to those of other species. It is capable of some rudimentary communication with Velociraptor antirrhopus, including throaty barks and gargling noises which are used to establish dominance and vocalize commands. It can also make a weaker version of the distinctive ringing bellow used by Tyrannosaurus rex to confront territorial rivals. Limited communication with Carnotaurus is also possible, consisting mostly of territorial vocalizations.

When frustrated, the Indominus can be heard screeching loudly.

Although it rarely socializes, some degree of body language is known in Indominus. When behaving aggressively, it gapes its jaw to show its teeth and mouth. It has been seen to assume body postures similar to the animals it is interacting with, notably Velociraptor. For example, while the arms are normally extended, Indominus may tuck them closer to its body when socializing with Velociraptors and raise its head higher. These raptor-like mannerisms help it establish itself as a dominant figure to these other animals.

Ecological Interactions

There is no known natural ecology for Indominus rex, as it is an artificially-engineered species.

Indominus threatens a large group of pterosaurs, Isla Nublar (12/22/2015)

When the one surviving specimen entered the wild, it was immensely destructive to its habitat as it engaged in excessive surplus killing. It killed a Brachiosaurus by ambushing it in a heavily-forested area, and later killed six Apatosaurus by lacerating them on the hips, chests, flanks, shoulders, and necks. It also killed one Ankylosaurus by biting its throat and snapping the spinal cord after overturning the animal. Later it was seen to behave aggressively toward Pteranodons, but was unable to kill any, and at one point threatened a Troodon but also was unable to make a kill. During scuffles with some of its victims, it destroyed local plant life due to its large size. The only species to really benefit from its presence are scavengers, such as birds seen feeding on the Apatosaurus carcasses.

A subadult female Indominus socializes with four female Velociraptors, Isla Nublar (12/22/2015)

The only intentional positive interaction the Indominus was shown to engage in was with four genetically-modified Velociraptors. Recognizing them as something similar to itself, the hybrid established some rudimentary communication with the raptors and formed a mutual symbiotic relationship with them. The raptors were smaller and thus more stealthy and agile than the Indominus, allowing them to pick off InGen Security personnel more easily; meanwhile, the sheer size and power of the Indominus would in theory protect the raptors. This relationship proved to be inherently unstable, however, as the Indominus could not tolerate any challenge to its authority. One of the Velociraptors, an individual named Blue, refused to kill Owen Grady due to her familial connection to the human who had raised her from infancy. The Indominus then became enraged and attempted to kill Blue, which turned the remaining raptors against the hybrid dinosaur. It proceeded to kill them.

Indominus may also be able to communicate with Carnotaurus, a theropod with which it shares a number of structural genes. During the 2015 incident, the escaped Indominus was involved with a brief territorial confrontation at the Carnotaurus paddock. The fence of the paddock was later found to have been broken from the inside, though the Indominus had pushed on it from outside. Furthermore, the escaped Carnotaurus that had been involved with the confrontation showed no signs of having been in a physical fight. This suggests that the Indominus weakened the fence enough for the Carnotaurus to escape, and did not fight the smaller dinosaur. However, the two did not cooperate after the escape either.

Partial remains of Indominus on the Jurassic World Lagoon seabed (June 2016; exact date unknown)

Indominus rex was seen to engage in combat with a female Tyrannosaurus rex, though in this case the tyrannosaur instigated the fight for territorial purposes. The Indominus likely would have been the victor, but due to complicated circumstances, was instead forced into a corner where it was preyed upon by a Mosasaurus.

What was left of its skeleton eventually became a habitat for benthic marine life and small fish.

The game Jurassic World: Evolution depicts the Indominus as becoming stressed if there are more than a handful of animals in its environment, lashing out violently as soon as it feels too crowded. It is also portrayed as being host to the bacterium Campylobacter, which can be found in up to 100% of some bird populations and is a common pathogen in many theropods in the game. This microorganism can cause campylobacteriosis.

Cultural Significance

Originally, the Indominus rex was meant to act as a symbol of Jurassic World’s scientific triumph and grandest achievement: the ability of its lead genetic biologist Dr. Henry Wu to manipulate the building blocks of life and create entirely new species. Predatory theropods were the primary sources of genetic material for this animal, which was meant to showcase the full range of hunting adaptations that dinosaurs had evolved during their history. To highlight this, the Indominus was marketed with the tagline “Bigger. Louder. More Teeth.” This marketing plan was highly effective and resulted in skyrocketing ticket sales to Jurassic World once the public learned that a new theropod was coming. Its identity was not even known yet.

The name of this organism was chosen by InGen to be frightening-sounding yet easy to pronounce. It roughly means “untameable king” in Latin. While the appeal of such a name is obvious, it inadvertently reveals some contradictory messaging within InGen; clearly this was an animal meant to entertain and thrill audiences with its ferocity, but despite its scientific name, it was actually intended to be maintained in captivity and controlled. Naming it something which described it as untameable would excite tourists but potentially give the wrong idea. Ultimately this contradiction did not matter because the animal escaped before being put on exhibit, meaning it did end up truly being untameable.

Simon Masrani first viewed the animal in late 2015 mere hours before his death, and was impressed by its aggressive behavior; rather than concern, he expressed admiration for the animal’s boldness. He was surprised to learn that it was white in color. In his native India, the color white is symbolic of purity, knowledge, cleanliness, peace, and sometimes mourning; this wide range of meanings is because white is essentially a combination of other colors of light. This is similar to how the Indominus was a combination of several other organisms and showed their traits, though it displayed predator traits rather than peaceful and intellectual ones. Perhaps more fittingly, the color white can be linked to the pallor of death. Masrani considered the Indominus a suitably terrifying new attraction which he hoped would draw in thrill-seeking crowds.

The revelation that Dr. Wu had been paid off to make the animal combat-oriented caused its reputation to turn completely around. Instead of standing for the wonders of modern genetic science, the Indominus came to symbolize hubris and greed, and how capitalist interests bring corruption to science. To some degree it represents American nationalism, since InGen’s Head of Security Vic Hoskins intended to sell it to the U.S. Armed Forces to help maintain American superiority on the battlefield.

In Captivity

Only one Indominus was kept in captivity with any measure of success, and even then it was fraught with problems all throughout. Having been bred in a laboratory, there was no prior information available about its needs or traits, only predictions. It was introduced to Paddock 11 sometime after hatching in 2012. The paddock was constructed specifically for the Indominus, but required several modifications as the animal grew and developed.

The walls were initially forty feet high, but were under further construction as of late 2015 due to concerns that the dinosaur might be able to scale them anyway. Feeding initially was carried out through slats in the paddock wall, but it eventually learned to predict where its food would come from and attacked staff during feeding. After one worker came close to losing an arm, the rest of the staff threatened to quit if park management did not take action; a new feeding policy was put in place with a large crane used to deliver meat to the paddock.

Observation was accomplished through a reinforced glass panel, which the animal tried to break in late 2015. It was not successful, managing only to crack the glass. By this time one of the two Indominus had cannibalized its sibling; there is currently no known way to keep more than one in captivity together. To keep track of the animal’s position, the paddock was equipped with surveillance cameras. The paddock was heavily forested, since the Indominus preferred to remain hidden. Because of this, the cameras were capable of thermal sensing, which could be toggled from the paddock control room. This would allow the Paddock 11 supervisor to view the animal when it was hiding in the trees.

An inspection of the paddock by InGen Security animal behaviorist Owen Grady revealed a more pressing problem with the habitat: it lacked any significant form of stimulation, which all intelligent animals require. It had no positive relationships except for with the crane that delivered its food. While this was a necessary precaution, it ensured that the Indominus viewed its keepers as enemies keeping it imprisoned rather than as caretakers. Without anything to do in its paddock, it became bored and frustrated, which may have contributed to its aggressive behaviors.

The way in which the Indominus was dealt with imply that it would instinctively be violent toward humans and other animals, though it is impossible to say for certain whether this is true. It seems very possible that this was a learned behavior rather than a fundamental part of its biology. Still, at this time there is no information available on how to actually, reliably keep an Indominus satisfied in captivity, and considering the intent behind its creation there may not be a way.


Before Indominus, the first animal species to be created through multiple-genome hybridization was its ancestor Scorpios rex in 2009, preceded by the flowering plant Karacosis wutansis in May 1997. Both these and other hybrid species were realizations of Henry Wu’s theory that brand-new species could be created through this kind of artificial genetic hybridization. While organisms belonging to different species can sometimes hybridize in nature, and even give rise to new species naturally, this is limited in effectiveness and can usually only occur between reasonably close relatives. The creation of the Indominus between 2009 and 2012 furthered the theory that it was possible to engineer new animal species using genes from only distantly-related organisms. It was considered to have more potential than the Scorpios, since its behavior was less erratic.

The creation of a healthy, virile Indominus was a major success for Dr. Wu’s career and for genetic science overall. In order to predict this animal’s traits, a full understanding of the functions of the genes of its source species was necessary; this probably necessitated sequencing the genomes of all those organisms. Once all the genes of interest were identified, they would be removed with precision and incorporated into the base genome being used as a template. This required use of the most advanced genetic engineering techniques yet developed by scientists, and probably helped to advance that technology in the process.

Computer modeling of Indominus physiology and genome

After it hatched, Indominus demonstrated virtually all of the traits that Wu had predicted it would exhibit, meaning that he had succeeded in not only identifying the functions of every gene he utilized but also in learning how to incorporate them into the genome of another animal while maintaining their functions. In some cases, there is evidence that he got more than he bargained for. Genes sourced from cuttlefish were allegedly intended to facilitate a rapid growth rate, but also appear to have resulted in chromatophores developing in the skin. The animal’s ability to hide from thermal scanners was also unexpected, but resulted from the Indominus being able to sense thermal radiation. By seeing its own heat signature, it could determine when it was hidden by modulating its body temperature until it could no longer sense its own heat. While the Indominus would not have known about the thermal scanners, its ability to hide in this manner would ultimately make it an even more valuable product for its ultimate intended purpose as a military animal.

In some ways, though, the Indominus was a failure. Its aggressive behavior and poor social skills made it theoretically impossible to train. This would make it useless in a military setting. To fix this problem, Wu began working on the genome to achieve behaviors more like those of Velociraptor, preferably including a tendency toward social structure. The results of this experimentation was the Indoraptor, the closest that Wu ever came to a completed military bioengineering product.


While the practice of military bioengineering would later become heavily controversial in American and global politics, it began with the Indominus rex in laboratory facilities in Jurassic World. While originally it was meant to be a park attraction, InGen Security’s Vic Hoskins understood that the park’s profits were unsustainable and believed that the solution was in a government partnership. Hoskins himself was a former member of the U.S. Armed Forces and had seen modern combat firsthand, considering it impossible to truly win wars anymore. All of his programs, the Indominus included, were intended to supplement the U.S. military’s arsenal and get the edge over other countries. The funding for the Indominus came from the Lockwood Foundation via its manager Eli Mills, who was less interested in helping maintain American superiority as he was in simple war profiteering.

At the moment, the American government has not made specific commentary on the Indominus or any other military bioengineering products. However, when Jurassic World closed down, the government raided laboratory facilities used by Dr. Henry Wu and seized all materials therein. It is unknown what the government has done with these resources, which included samples of Indominus DNA. While there are heavy restrictions on biological warfare on an international scale, these are swiftly made outdated by advancements in science; there is no precedent for a macroscopic organism being engineered for war, and the legality of creating and/or using one in this manner is extremely ambiguous.

Along with what it means for warfare, the Indominus has added fuel to the fire of the genetic engineering debate. It has been used as evidence that genetic power will invariably be used to cause harm, and even used to support the argument that de-extinction itself is a dire threat. This is not exactly a valid argument, as the Indominus is not a de-extinct species at all. The real danger of the Indominus was not even the fact that it was genetically engineered; instead, it was the corruption behind its creation that caused it to be developed into a weapon. Curiously, the Indominus has been noticeably absent in debates surrounding the morality of capitalism and warmongering, although it should be more at home here than anywhere else in politics.


The creation of the Indominus was authorized by Simon Masrani and Claire Dearing on April 4, 2008 after a unanimous decision of the Board of Directors that Jurassic World needed a new attraction to boost attendance. Over the next four years, Dr. Henry Wu would work with InGen’s genetics division to engineer this animal, with his only instruction being that the animal be “cooler” than anything they had created before. Its first incarnation was called Scorpios rex, but this animal was a failure. At some point during the development process, head of InGen Security Vic Hoskins approached Dr. Wu with a proposition on behalf of Eli Mills to make Indominus combat-oriented and suitable for use by military organizations; in exchange, Wu’s research would be funded by Mills. Wu accepted the offer.

Simon Masrani revealed the animal’s existence to the public in January of 2015 on his corporate blog after hinting about it for several months, though its name and hybrid nature were only known to a smaller and more private audience. He himself would not actually see it until his repeatedly-delayed visit on December 22 of that year. It was marketed with the tagline “Bigger. Louder. More Teeth.” After its public reveal, online ticket purchases to Jurassic World skyrocketed. Ironically, this same animal would later force Jurassic World to close due to bad publicity following a series of incidents it caused across Isla Nublar.

Ultimately, the Indominus proved unfit for military applications due to its violently aggressive behavior. Hoskins had proposed creating smaller versions of the animal, hopefully making them more suitable to accept the training regimen which had already been proven effective with Velociraptors. The result was the creation of Scorpios rex, and later the Indoraptor.


Numerous human and animal deaths were attributed to this species, though all over the course of just a couple hours on December 22, 2015. By the end of the night, this dinosaur had been killed, and since it was the only remaining member of its species, Indominus is now believed to be extinct. However, samples of its DNA were obtained by the U.S. government during raids on Henry Wu’s laboratory facilities, and while there is no evidence that it has been bred, we at Jurassic-Pedia are not about to assume that the government is above doing so (or quietly selling to someone who would). Accordingly, we have assembled what little information there is about defending yourself from an Indominus assault.

This is a heavy-hitting, well-defended organism, and conventional weapons are not extremely useful against it. Unless you are heavily armed with good aim and military training, we do not suggest fighting it; instead, focus on getting yourself someplace safe that it cannot reach you. With some large animals, hiding in a vehicle is a safe bet, but we do not suggest it with Indominus. The bulk of this animal allows it to flip most vehicles over, even rather large ones, and its natural weaponry can make short work of even sturdy vehicle frames. Instead, try hiding inside a building with firm foundations and solid walls. Simple drywall or thatch is useless as the Indominus can pound through them. Glass, and even reinforced polymer, is similarly no obstacle for it.

In terms of its natural armaments, Indominus basically has two methods of attack: its jaws and its claws. Should it get its mouth around you, it will probably bite down to kill right away, so we will focus on what to do if it gets its strangely dexterous hands on you. This dinosaur is fast, capable of outrunning a human, so trying to evade it in a straight line will most likely not work unless there is a slower person nearby. Instead, try using your smaller size to your advantage, dodging to the left and right and avoiding its claws. It will try and grab you, lifting you up to its mouth to bite down and tear you apart. Ideally you should try to escape before this happens, so try to take it by surprise and make it drop you. It can be startled by loud sounds, bright lights, and sudden physical stimuli; electric shocks and explosions seem to be effective, but if you do not have these kinds of weapons on you, try something else. It is heavily armored on most of its body, but its face has several weak points. Its eyes are an obvious vulnerability, but the soft interior of its mouth is another (not to mention probably the last one you will have a chance to attack). The nostrils and ears of most animals are also weak points, and Indominus additionally has heat-sensing pits which might be possible targets. Should it drop you, be prepared to tuck and roll out of the way of its feet, and flee in whatever direction is most inconvenient for it to turn and follow.

Hiding from this creature is a bit of a challenge, but not impossible. As mentioned previously, it can “see” heat by sensing infrared radiation, and as a warm-blooded creature you will easily stick out to it. Get creative in your efforts to mask your heat signature: InGen animal behaviorist Owen Grady was able to evade an Indominus by hiding underneath a large vehicle which had been sitting out in the tropical sun. The heat of a Central American day on the metal of the vehicle’s body masked Grady’s own thermal signature, making him blend in. Furthermore, he used gasoline to mask his scent, and later used Indominus dung for the same purpose. If you cannot douse yourself in anything strong-smelling but decidedly not what the Indominus wants to eat, water will also work. Two unarmed civilians during the 2015 incident were able to dive into a small pool to hide, remaining underwater until the Indominus left. Deep enough water will hide you from its senses, and also wash off your natural scent for a time.

Stay in your hiding place for longer than you assume you need to, preferably until you hear from someone else that the danger has genuinely passed. If you expose yourself too soon, you may find that the dinosaur has lurked nearby and is waiting to ambush you. Just because you can’t see it does not necessarily mean it isn’t there; it is able to camouflage itself in forested environments (and presumably elsewhere) by rapidly changing the color of its skin. Remember that this is a highly intelligent predator, capable of problem-solving and predicting your behavior. You must be smarter than it in order to survive. Fortunately, that is one department in which you probably are better off: while the Indominus is undoubtedly one of the smartest dinosaurs, and one of the smartest animals overall, you belong to the species that it owes its existence to. Stay alert and you may be able to outwit it and live another day.

Behind the Scenes

In earlier stages of development, this animal went under the name “Diabolus rex,” meaning “devil king” or “king of devils.” It went through several design variants, including one which featured a larger set of fang-like teeth and one which highlighted its carcharodontosaurian traits.

Another earlier version of Jurassic World would have featured this animal as a newly-discovered but naturally-occurring allosaur species found in China called Malusaurus (meaning “bad/evil reptile”); director Colin Trevorrow disagreed with this decision and instead pushed for Indominus to be an artificially-created creature. This ultimately makes more sense, as the park had been creating dinosaurs for upwards of ten years at that point and should not, reasonably, fail simply because another new creature was discovered. Furthermore, featuring the Indominus as a “real” dinosaur found by paleontologists would likely confuse audiences. Finally, the theme of the franchise overall is that attempting to control nature inevitably leads to harm; the Indominus being an attempt to manipulate nature is more thematically appropriate than it being a natural animal which, for no particular reason, can destroy the park.

Some aspects of its anatomy and genetics were designed directly by the filmmakers, whereas other aspects were suggested by contributors. For example, the idea of its lanky arms being the result of Therizinosaurus genes was suggested by Dr. Jack Horner. Some animals referenced for its appearance that are not official parts of its genetic makeup include Allosaurus, Monolophosaurus, and Cryolophosaurus.

Notable Individuals

Indominus Siblings – only two members of this species known, hatched in 2012

Disambiguation Links

Indominus rex (L/M)