When Owen, Maisie and Alan have Beta cornered in the boiler room, she's trying to decide who to attack first and settles on Alan. Why? Because one, he's the oldest of the trio and therefore the weakest, something Blue would have taught her about picking out targets. Two, he's the stranger of the three and therefore, doesn't count as "pack"; Maisie bonded with Beta at least twice up to this point and earned her trust, and Beta has seen Owen and her mother interact somewhat amicably at least once so he also counts as part of the "pack". Three, Blue would have "told" her that Owen is or at least once was her alpha and thus worthy of respect as a pack member, not prey.
Those with in-depth knowledge of Giganotosaurus will know that it could not have killed a Tyrannosaurus rex by breaking its neck. However, because Giga and its relatives had teeth designed for slicing and cutting through thick flesh, it's plausible that the Giga in the prologue killed the T. rex by managing to slice open its jugular or tear out its throat instead.
It's also noticeable that the scene cuts to the Giga's foot nearly slipping off the ledge as it battles the T. rex. Since the Giga's teeth could only slice rather than crush, the most likely explanation for its victory is that the Giga took the T. rex to that same unstable ledge and let gravity pull the heavy dinosaur, causing the T. rex's neck to be torn to shreds as it slides through the Giga's razor teeth.
When Owen mistakes the Giganotosaurus for an Allosaurus, he's not too far off. Both dinosaurs are from the same family, Allosauroidea.
While the Giganotosaurus has a few anatomical oddities compared to the real animal, the stylized elements of its design make it easy to see the influence its genes had on the Indominus rex and Indoraptor, with the dorsal spines, teeth, body proportions, and even its roar being extremely similar to the hybrids.
In the prologue, the T. rex is running away from a Fish and Wildlife Service helicopter and manages to dodge a tranquilizer. This shows she has learned to recognize that helicopters mean danger, as she was likely shot with a tranquilizer from a helicopter when she was originally recaptured by Masrani prior to Jurassic World and later by Mills’ goons in Jurassic World: Fallen Kingdom.
Why do the Dimetrodon roars sound almost like human screams? Anyone who knows about the Permian period or watched Walking with Monsters would probably tell you that one of humanity's most primordial ancestors are these creatures.
Along with series veterans T. rex, Velociraptor, and Carnotaurus, Dominion introduces Therizinosaurus and Giganotosaurus to the movies. These five species were the major genetic components of the Indominus rex.
Despite the fears laid out at the end of Jurassic World: Fallen Kingdom, the dinosaurs are not ecological disaster threatening humanity's survival. At worst, they became invasive species that often come into conflicts with humans and other wild animals, but the big ones can be contained and monitored by governments and wildlife organizations. In short, dinosaurs are Awesome, but Impractical to actually deal real extinction to humanity. So what genetically engineered monster(s) can really cause human extinction? Small creatures that breed rapidly and compete for the same food sources as humans, aka Biosyn's locusts. These modified hybrid insects are the most destructive and dangerous genetic lifeforms on the planet because they specialize on consuming the plants that feed billions of people. Without adequate food supplies, billions of people will starve to death, creating the mass extinction event that the dinosaurs, even hybrid dinosaurs, alone could never achieve.
The most dangerous and feared Prehistoric Monster in Dominion as well as probably the franchise as a whole, is not a giant Super-Persistent Predator, but a tiny Explosive Breeder herbivore: the prehistoric locusts. Chaos comes from the changes in smallest things, after all.
Rexy's fight with the Giganotosaurus has several call backs to her predecessor's Cretaceous battle including the Giga using its head as a battering ram, and Rexy being partially overcome because of environmental circumstances (the prehistoric rex's feet slipped over an incline, making it easier for it to be garotted while part way through the fight Rexy slips down the entrance of a subterranean staircase, allowing the Giga to pin her head beneath it's feet and begin dominating the fight.
Maisie's backstory on the surface seems contradictory and full of plot holes between the "official" and "cover" stories, but it actually makes perfect sense once you look at it from the start, and some evidence shown in the movie. Based on the Isla Nublar videos, Charlotte Lockwood was likely born around 1972, and Dr. Wu implies that she was a very bright kid, possibly even a Child Prodigy who became a geneticist early in her life. She'd have been 21 when the first film's events happened, and thus around this time began working on having a child by cloning herself. Eventually, Hammond found out about this, and when Benjamin Lockwood stood by Charlotte, it caused their falling out, hence Hammond's actions in the same movie. After Hammond's death, Charlotte still lived a regular life, and gave lectures like the one she did at Ellie Sattler's university, where she befriended and confided in Ellie of her efforts to have a child. In all of Charlotte's videos, she's alone in the basement labs of her home; it's more than likely that she did all of the research into her self-cloning by herself with no outside help, to the point where she spent all her time in the her home labs and not interacting with the world, effectively disappearing. It took her multiple years to finally perfect the complex cloning process on a human, which allowed her to have Maisie. Then upon discovering her own genetic illness, she quickly worked to clean it out from Maisie as her last act in life. As this was in 2009, Eli Mills—assuming he shares Rafe Spall's age—would have recently finished college and been hired to handle Lockwood's finances, and thus unlikely to be let in on the secret. Thus, only Iris Carroll, Henry Wu, John Hammond, Ellie Sattler, and Benjamin Lockwood likely knew the truth. However, there still needed to be an explanation for a young girl living in the Lockwood estate. Wishing to preserve his daughter's legacy, and because no one had seen Charlotte Lockwood for years, it would've been easy for Lockwood to come up with the cover story for Maisie's background, falsely claiming to outsiders (like Mills) that Charlotte died in a car accident years earlier and that Maisie was his granddaughter with the "truth" being that he spent years trying to clone her since then until he finally succeeded and Maisie was born. In addition, this movie makes it clear that Maisie's existence was largely kept secret from the outside world, meaning no one knew that Lockwood supposedly had a granddaughter even though his own daughter supposedly died years earlier.
Nedry in the first film was not at all intimidated by Dodgson's threats. Considering the latter's incompetence in this film, it is not hard to see why.
While she is a juvenile, Beta is actually the size of Velociraptor in real life. This way, the movie is demonstrating that the 3-foot-tall dromaeosaur was still deadly like its counterparts in the franchise.
Fridge Logic
The anachronistic nature of the fauna in the prologue can be a little jarring for people familiar with what dinosaurs lived where and when. Very few of these animals were even co-eval let alone sympatric. This seems odd as many comments surrounding the prologue emphasized its intent to present the animals more realistically than the main films. But when you consider that the prologue likely has a much smaller budget than the main film, it's highly unlikely that they had the money to create new models for it. The species included were most likely "chosen" because they were already fully rendered for the film and were the only assets available to use. The realism therefore comes from the animals behaviour, which was widely praised.
On that note, the Giga's unusual appearance in the prologue raises the question on whether the Biosyn Giga is a pure strain considering the T. rex in the prologue has feathers but Rexy doesn't.
The chip that Biosyn puts in the dinosaurs' heads leads them to shelter during the climactic forest fire, but it doesn't stifle their behavior whatsoever. Once they're all together, Rexy and Giganotosaurus duke it out, which carries unfortunate implications for the herbivores side-by-side with carnivores. Did no one stop to consider this?
Jurassic World: Camp Cretaceous established that predators and prey can coexist side-by-side without killing one another if brought together because of something mutually beneficial, be it a watering hole or escaping from a large-scale disaster. Unless Biosyn has an Indominus or a Scorpios rex lurking somewhere in its compound, the herbivores have little to fear.
Why is Rexy willing to fight to the death against the Giganotosaurus in the finale if she was clearly capable over retreating even when food is at stake? When she encountered the Giga in the forest, she reacted in a normal manner, fighting for food and retreating when there was too high a risk of injury. However, she's not in the Biosyn facility out of choice. She's been compelled to enter and is still under that compulsion. She can't leave any more than the Giga can, and so this becomes a similar situation to the Indominus where she's now compelled to drive an intruder out of a space she must remain in.
If the Buck and Doe tyrannosaurs had been living in the Biosyn valley, presumably brought over from with the initial wave of Sorna migrants, why was the Giganotosaurus the apex and only challenged when Rexy was introduced? Surely a pair of T. rexes would have ousted it.
Maybe, but remember they grew up and lived most of their lives in an environment which they shared with a large variety of predators, including other tyrannosaurs and perhaps most significantly the Spinosaurus. They would have been familiar with what it's like living alongside competitive predators and likely learned to avoid conflict as much as possible. Attacking the Giga puts them at unnecessary risk. Rexy on the other hand has lived almost her entire life as the only giant predator in her ecosystem, and has only once met a carnivore in her weight class. She's not only not used to having to compete with others, she's never had to back down from anyone. So while she may not stay to fight the Giga over a single deer carcass, when they both occupy the same immediate area she's much more likely to simply launch herself at a competitor. Factor in that she's also larger than the other two rexes which means one on one she's more intimidating to the Giga and it's likely she's the only predator in the valley who would have gone out of her way to pick a fight.
Fridge Horror
While by this movie Dr. Wu is clearly regretful of having played god through genetic engineering for so long, by the end of the movie he's found a way to quickly wipe out entire species. It's understandable why Charlotte didn't keep notes of her research on Maisie, and the movie makes you wonder whether Wu will do the same after taking care of the locusts.
That said, his Heel Realization does at least seem genuine, and if not he has all the heroes on hand to make sure that he'll just deal with the locusts and then delete his work so that he can't do anything further without the willing aid of Maisie in particular.
Actually Wu's plans are nothing new. In reality, scientists are engineering infertile mosquitoes to prevent the spreading of diseases. The engineered animals mingle with the wild ones but don't reproduce. Wu's work could help saving billions of dollars and years of research since he's the one who knows everything about the locusts. That doesn't give him the power to eradicate any species he wishes.
The two T. rexes seen in the end are confirmed to be the Buck and Doe from The Lost World. Conspicuously, however, the baby is missing. It would have grown up by then, but then one remembers the noticeably small T. rex the Spino kills in JP3...
For that matter, where are Big Eatie and Little Eatie?
According to the Grand Finale of Camp Cretaceous, probably still on Mantah's island.
Regarding Junior from The Lost World being the rex that the Spinosaurus ended with a Neck Snap, Matt Winston jossed that, after joking that it was confirmed.
Raptors in-universe are confirmed to produce clutches of eggs, so Blue having only one child which she is extremely protective of implies she may have lost the rest of her young to other predatory dinosaurs, or maybe even to full-grown modern predators.
Or maybe they were poached/stolen from her by humans. The possible results of that are endless and none of them are good.
Since Blue is now capable of self-reproduction, who's to say that her child Beta isn't capable of doing the same as well? Not only that, the Dino Tracker viral marketing website established that at least a couple of the Velociraptors from Isla Sorna made it to the mainland somehow, and we know for sure that they can reproduce as well. Alan Grant's fears of Velociraptors threatening humanity's dominance in the ecosystem in the third movie could prove true yet as the raptors are capable of reproducing themselves, and this time they're no longer confined to the islands, but out loose in North America. One or a few raptors are already troublesome to deal with. Imagine how much damage whole packs of wild Velociraptors will be capable of.
Blue was only able to achieve parthenogensis because, as Wu stated, she was specifically created with monitor lizard DNA. That said, the other raptors are dimorphic and would still be able to breed the old-fashioned way.
For that matter, Maisie may well be capable of parthenogenesis, and have a daughter as a virgin birth. Truly Fridge Horror.
How is Maisie self-reproducing Fridge Horror?
What are the triggers? Do they require Maisie to be a minimum age or could we have a 14-year-old finding herself pregnant with no idea what happened? And if they try to get her medical help, how many people would believe she's a clone with dinosaur genes and not that she was abused by the men looking after her? Do the dinosaur genes mean she will be like other humans in which it is normally single births with some twins and triplets and occasionally more or more like dinosaur in numbers which, given how much room a single baby can take up in a mother, could prove fatal if the number is large enough to literally tear her open?
Maisie is simply an intentionally cloned genetic copy of her mother created as a zygote or a fetus, then gestated and raised conventionally. She is not part monitor lizard which is the mechanism that allowed Blue to asexually reproduce.
During the final battle, while Rexy in unconscious, there is a brief moment where she flashes back to the death of her ancestor 65 million years ago. Right after this, she wakes up and starts her Heroic Second Wind. Was this flashback just a stylistic choice, or did Rexy somehow remember her past self's death? And if that's the case, what else does she remember? Has Rexy known for a long time that she is from a different world? This implies that, somehow, some of the dinosaurs' memories passed onto their clones genetically, and the smarter ones may be aware that they do not belong in the modern day. Imagine not only finding out that the world you came from is long gone, but also remembering your own death!
As noted in What Happened to the Mouse?, there's the matter of Denise and the other Biosyn employees after Dodgson gives the order to allow the dinosaurs into the facility. Sure they're seen proceeding to the exits with haste but we never see them actually leaving. Did they all make it out of Biosyn Valley safely without running into any dinosaurs, namely Rexy, Buck and Doe, Giganotosaurus, Dilophosaurus or any of the other carnivores, or that territorial Therizinosaurus? And if they flew, how did they get past Quetzalcoatlus and the other flyers with the Aerial Deterrent System still down?
