They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is a subject of active research.

Dec 22, 2025 · Dinosaurs are a diverse group of reptiles that were the dominant terrestrial life form on Earth during the Mesozoic Era, about 245 million years ago. Dinosaurs went into …

Non-bird dinosaurs lived between about 245 and 66 million years ago, in a time known as the Mesozoic Era. This was many millions of years before the first modern humans, Homo …

Oct 27, 2009 · Dinosaurs mysteriously disappeared at the end of the Cretaceous Period, around 65 million years ago.

Aug 16, 2025 · The era when dinosaurs flourished is known as the Mesozoic Era, often called the “Age of Dinosaurs.” This vast geological interval began approximately 252 million years ago …

Jul 21, 2024 · Explore the dinosaurs, marine animals, and other life from the Triassic, Jurassic, and Cretaceous periods.

Jul 31, 2025 · The age of dinosaurs—also known as the Mesozoic Era—is divided into three periods: the Triassic, the Jurassic, and the Cretaceous. This stretch of time, from about 252 to …

Jan 30, 2025 · During the Triassic Period, dinosaurs first appeared, marking a significant point in evolutionary history. The Jurassic Period followed, showcasing the rise of large herbivores and …

Jun 21, 2023 · Dinosaurs roamed Earth for millions of years, during a major geologic era known as the Mesozoic. Fossils, scientific discoveries and tireless research efforts have gradually …

Dec 6, 2022 · Dinosaurs dominated the Mesozoic Era for more than 160 million years, peaking during the late Jurassic to early Cretaceous periods. They are thought to be the most …