The Island of Isla Nublar

Alternate Scenario: "Island of Eternal Dinosaurs" The island, a lush paradise twice the size of present-day New Zealand and located far from the mainland, was a refuge for the diverse groups of dinosaurs, pterosaurs, crocodiles, and polyglyphanodontian lizards before, during, and after the KPG mass extinction event on the mainland. This isolated island was uniquely spared from the catastrophic forces that claimed the rest of the world, preserving the habitats of the forests, swamps, and open fields nestling in both tropical and temperate climates. Unscathed by the apocalypse, the island thus became a cradle for the continuation of the prehistoric life and evolution. Free from competition from the large mammals of mainland North America, these animals thrived and evolved throughout the Cenozoic era. Tyrannosaurs adapted into a greater variety of sizes and morphologies, some becoming smaller and more agile, while others evolved to enormous sizes, capitalizing on the absence of large land mammals. The omnivorous therizinosaurs, with their long necks and claws, evolved to be even more specialized, filling the ecological niche of giraffes and other browsers. Oviraptorosaurs, already showing bird-like characteristics, developed into an array of forms mimicking the various functions of modern-day bird groups. Some species of dromaeosaurs grew larger, becoming apex predators. Meanwhile, the herbivorous ornithomimosaurs, hadrosaurs and thescelosaurids roamed the open fields, evolving antelope-like adaptations for speed to evade these predators. Similarly, the island's aquatic inhabitants, the Cretaceous crocodiles and champsosaurs, dominated the coastlines and swamps. The enormous titanosaur sauropods, alongside ankylosaurs and ceratopsians, flourished without the threat of heavy terrestrial predators. The pachycephalosaurs, with their dome-shaped skulls, may have developed even more elaborate head structures and behaviors, similar to modern-day ungulates. In the sky, pterosaurs prevailed, diversifying into a wide range of sizes and forms to occupy ecological niches normally filled by birds. When humans arrived on the island during the late Pleistocene or early Holocene, they found a land teeming with creatures from a lost age. These first settlers learned to coexist with this unique ecosystem, revering the dinosaurs as living ancestors and adopting a balanced lifestyle to minimize competition with the prehistoric fauna. In this alternate universe, life took a different route, and the Age of Dinosaurs continued, creating a world where giants of the past meet the architects of the future.