DICRAEOSAURUS

Dicraeosaurus hansemanni

Etymology: Hansemann's bifurcated lizard

Nickname: "Dic" or "Dicra"

Classification: Sauropoda, Dicraeosauridae

Diet: Herbivore

Size: 14 to 24 meters long

Provenance: Tendaguru Formation, Tanzania - Late Jurassic, Kimmeridgian-Tithonian stage, 155 - 145 million years ago

Movie appearances: Jurassic World (2015); Jurassic World: Fallen Kingdom (2018); Jurassic World: Dominion (2022); Jurassic World Rebirth (2025)

Dicraeosaurus hansemanni is a dicraeosaurid sauropod, and among the giant Jurassic herbivorous species to be described the earliest, back in the early 20th century. Characterized by a small head in comparison to a long neck and large body, as typical for sauropods, these herbivores have to be constantly feeding to stay well fed. Therefore, except when sleeping, these herbivores spend most of their waking hours consuming plants. Because they can't chew, Dicraeosaurus benefit from a large belly to ferment the tough vegetation that they consume, and sometimes they also consume rocks as they munch a lot on low-lying fodder.

The largest Dicraeosaurus individuals appear to have grown considerably larger than what the fossil record would otherwise suggest, reaching up to 24 meters long, though their average adult size is about 14-16 meters long. They typically have bluish-gray skin, but some may present bluish stripings, as well as patches of dark tan on the underbelly and face. Like its larger diplodocoid cousin, the Barosaurus, it uses its needle-like teeth to strip soft vegetation and swallow it whole without chewing.

Dicraeosaurus is recognized to be a rather docile and gentle herbivore. They don't seem to show any major preparations to defend from large megapredatory theropods, interestingly, with them easily falling prey to the giant Indominus rex. Their lifestyle is generally defined by a peaceful existence with little need for conflicts and defensive mechanisms. Dicraeosaurus do possess a long whip-like tail that can be used as a rudimentary weapon, though it doesn't exactly provide much damage against a giant predator anyway.

Dicraeosaurus were resurrected for Jurassic World in the early-mid 2000s on Isla Nublar, and were left to live in the Gallimimus valley, the Gyrosphere valley and the Cretaceous Cruise, coexisting with creatures such as Stegosaurus and Microceratus. Dicraeosaurus eventually became feral once Jurassic World was closed during the escape of the Indominus rex, in 2015; these sauropods eventually would later form mixed herds with Barosaurus in Isla Nublar. These sauropods were often threatened by the largest predators of the island, and their reaction usually led them to stampede and run away from the threat, indicating a preference for running rather than standing their ground against a predator, and the same applied to the Barosaurus, curiously.

In 2018, Isla Nublar's Mount Sibo erupted, threatening the lives of the resident Dicraeosaurus, but a few were saved by a team of mercenaries that transferred them to Lockwood Manor, in mainland California, where they eventually escaped and became feral in the american continent.

However, by the mid-2020s, the once thriving de-extinct dinosaur population started to disappear in the non-tropical regions of the world, with the very last Dicraeosaurus alive in the US, nicknamed "Bronto-Billy", seen dying on a street in New York City, with the police blocking off the area around the dying sauropod, believed to be the last one left in North America. Several cranes were put in place to help lift the animal before it collapses. However, Dicraeosaurus are still alive in a refuge ecosystem in Ile Saint-Hubert, a tropical island in the Caribbeans that was used by InGen in the 2000s to test on de-extinct dinosaur genetics before implementing their research on Jurassic World.

FILM vs. REALITY

DISCLAIMER: Dicraeosaurus does not show up in the Jurassic Park films, and it instead, here, represents a plausible substitute to the films' Apatosaurus. The films' Apatosaurus has some differences to its real life counterpart, namely its size, with individuals in the film appearing much larger than the fossil estimates tell us, even though sauropod adult size could have been quite variable, to the point that some very old individuals could have grown much larger than normal (with that said, there doesn't seem to be enough time in the franchise's chronology for very old individuals to exist). The Apatosaurus in the film is depicted with a relatively standard neck for a sauropod, when the real life one had much broader necks, perhaps used for intraspecific combat. Because of that it also appears rather unlikely that an Apatosaurus would be so defenseless even towards large predators such as Indominus rex, being well prepared to send powerful bone-shattering blows with its neck.

Dicraeosaurus is distinguished from Apatosaurus for being considerably smaller, and having a shorter neck that wouldn't really be useful for the same combat skills as its larger diplodocid relative. Because of that it would appear like a more plausible candidate to fall prey for a large predator like Indominus rex. Like Apatosaurus, it preserves the typical whip-like tail of diplodocoids, and its overall large length. Although in some films, the immense scale of Apatosaurus is used for great spectacle purposes, it would be feasible to speculate that even more modestly sized sauropods, like Dicraeosaurus, could have large old individuals that grew much larger than other typical younger adults, therefore allowing their large scale to produce a similar effect. Unlike the Apatosaurus from the film, Dicraeosaurus wouldn't have elephantine-like front feet, and instead have clawless horseshoe pads, with only one large claw on the side of each front foot. Additionally, the films' Apatosaurus is shown with fleshy lips, when it would be expected for Dicraeosaurus and kin to have a tougher immobile facial integument covering their lips, probably even with some corneous appearance. Finally, as is typical of sauropods, Dicraeosaurus wouldn't have chewed its food, only using its teeth to strip the vegetation and swallowing it whole, which is unlike the films' Apatosaurus that performs chewing inaccurately.