Stegosaurus (/ˌstɛɡəˈsɔːrəs/[1]), from Greek stegos (στέγος), which means roof, and sauros (σαῦρος), which means lizard, is a genus of herbivorous thyreophoran dinosaur. Fossils of this genus date to the Late Jurassic period, where they are found in Kimmeridgian to early Tithonian aged strata, between 155 and 150 million years ago, in the western United States and Portugal. Of the species that have been classified in the upper Morrison Formation of the western US, only three are universally recognized; S. stenops, S. ungulatus and S. sulcatus. The remains of over 80 individual animals of this genus have been found. Stegosaurus would have lived alongside dinosaurs such as Apatosaurus, Diplodocus, Brachiosaurus, Allosaurus, and Ceratosaurus; the latter two may have preyed on it. These were large, heavily built, herbivorous quadrupeds with rounded backs, short fore limbs, long hind limbs, and tails held high in the air. Due to their distinctive combination of broad, upright plates and tail tipped with spikes, Stegosaurus is one of the most recognizable kinds of dinosaurs. The function of this array of plates and spikes has been the subject of much speculation among scientists. Today, it is generally agreed that their spiked tails were most likely used for defense against predators, while their plates may have been used primarily for display, and secondarily for thermoregulatory functions. Stegosaurus had a relatively low brain-to-body mass ratio. It had a short neck and a small head, meaning it most likely ate low-lying bushes and shrubs. One species, Stegosaurus ungulatus, is the largest known of all the stegosaurians (bigger than related dinosaurs such as Kentrosaurus and Huayangosaurus). Stegosaurus remains were first identified during the "Bone Wars" by Othniel Charles Marsh at Dinosaur Ridge National Landmark. The first known skeletons were fragmentary and the bones were scattered, and it would be many years before the true appearance of these animals, including their posture and plate arrangement, became well understood. Despite its popularity in books and film, mounted skeletons of Stegosaurus did not become a staple of major natural history museums until the mid-20th century, and many museums have had to assemble composite displays from several different specimens due to a lack of complete skeletons. Stegosaurus is one of the better-known dinosaurs, and has been featured in film, postal stamps, and many other types of media.
In January 2024, a new installment was revealed to be officially in development. David Koepp will return as screenwriter while Frank Marshall and Patrick Crowley once again serve as producers. Steven Spielberg will serve as executive producer, with the project being seen as a joint-venture production between Amblin Entertainment and Universal. Development of the project had been underway for some time, with several drafts already written by Koepp. The producers had also done some pre-production work, including dinosaur designs, meaning that any creative input from the eventual director would be minimal. The position was reportedly described as being "more shooter than auteur", as the producers sought to have more creative control compared with Dominion. David Leitch was briefly in talks to direct the film during early February 2024, but negotiations broke down after several days, as the project's progress up to that point left little room for his creative input. Soon after Leitch's departure, Gareth Edwards was announced to direct the film, with Scarlett Johansson and Jonathan Bailey in talks for the lead roles. Paleontologist Steve Brusatte will return from the previous film as dinosaur consultant. Filming is scheduled to begin in June 2024, at Sky Studios Elstree in the United Kingdom. Filming will also take place from July to September at the Malta Film Studios in Kalkara, Malta. The untitled film is scheduled for a July 2, 2025 release.
