Stromatolite (Cothan Marble), Triassic, UK

Triassic Information

The Triassic Period (252–201 million years ago) marked the beginning of the Mesozoic Era, following the Permian-Triassic mass extinction, the most severe extinction event in Earth's history. The climate was hot and dry, with vast deserts and little polar ice. Life slowly recovered, leading to the rise of the first dinosaurs, pterosaurs (flying reptiles), and early mammals. Reptiles, including large archosaurs (ancestors of crocodiles and dinosaurs), dominated both land and sea. In the oceans, ichthyosaurs and plesiosaurs thrived alongside ammonites and early coral reefs. The first true conifers and ginkgo trees spread across the land. The period ended with another mass extinction, paving the way for the Jurassic and the golden age of dinosaurs.