When did dinosaurs evolve, and what did the first ones look like? The earliest definitive dinosaur is not one animal but an entire ecosystem containing a few different species. There's no universally accepted dinosaur species that lived earlier in time.

The first dinosaur fossils were recognized in the early 19th century, with the name "dinosaur" (meaning "terrible lizard") being coined by Sir Richard Owen in 1842 to refer to these "great fossil lizards".

2023年6月21日 · 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 unveiled the mesmerizing tapestry of the dinosaur timeline.

2017年3月20日 · The first true dinosaurs --small, two-legged, meat-eating reptiles--evolved in what is now South America during the middle to late Triassic period, about 230 million years ago, and then spread around the world.

2019年7月20日 · About 230 million years ago--give or take a few million years--the first dinosaurs evolved from a population of archosaurs, the "ruling lizards" that shared the earth with a host of other reptiles, including therapsids and pelycosaurs.

2025年1月23日 · Scientists propose location for dinosaur birthplace; They point to Sahara desert and Amazon rainforest regions; Oldest-known dinosaur fossils about 230 million years old

The Triassic was the first period of the Mesozoic Era. Discover what animals lived in the Triassic Period, which were the first dinosaurs and what prehistoric plants they lived alongside.

2022年7月8日 · The earliest true dinosaur fossils date to the early part of the Late Triassic, but it is very unlikely that we have found the actual very first dinosaurs, and the group probably originated in the Middle Triassic or Early Triassic. We have a general picture of the closest relatives to dinosaurs.

2025年1月8日 · How and when did dinosaurs first emerge and spread across the planet more than 200 million years ago? That question has for decades been a source of debate among paleontologists faced with fragmented fossil records.

2020年7月29日 · The classic dinosaur family tree has two subdivisions of early dinosaurs at its base: the Ornithischians, or bird-hipped dinosaurs, which include the later Triceratops and Stegosaurus; and the Saurischians, or lizard-hipped dinosaurs, such as …