Evolution of dinosaurs
Dinosaurs evolved within a single lineage of archosaurs 232-234 Ma (million years ago) in the Ladinian age, the latter part of the middle Triassic. Dinosauria is a well-supported clade, present i...
Evolution of dinosaurs - Wikipedia
Study Shows Climate Change’s Surprising Toll On Early Dinosaurs
For years, scientists have puzzled over an odd gap in the fossil record for early dinosaurs: Even as dinosaurs spread through the most of the world 200 million years ago, some yet-unknown force kept t...
How Birds Evolved From Dinosaurs
Modern birds descended from a group of two-legged dinosaurs known as theropods, whose members include the towering Tyrannosaurus rex and the smaller velociraptors. The theropods most closely related t...
Evolution of reptiles
Reptiles arose about 310-320 million years ago during the Carboniferous period. Reptiles, in the traditional sense of the term, are defined as animals that have scales or scutes, lay land-based hard-s...
Cretaceous-Tertiary extinction event
The Cretaceous–Paleogene (K–Pg) extinction event, formerly known as the Cretaceous–Tertiary (K–T) extinction, was a mass extinction of some three-quarters of plant and animal species on Earth—includin...
Cretaceous-Tertiary extinction event - Wikipedia
Evolution of mammals
The evolution of mammals has passed through many stages since the first appearance of their synapsid ancestors in the late Carboniferous period. By the mid-Triassic, there were many synapsid species t...
Evolution of mammals - Wikipedia
Squamata
The Squamata, or the scaled reptiles, are the largest recent order of reptiles, comprising all lizards and snakes. With over 9,000 species, it is also the second-largest order of vertebrates, after th...
Squamata - Wikipedia
Sphenodontia
Rhynchocephalia is an order of lizard-like reptiles that includes only one living genus and species, the tuatara (Sphenodon punctatus), which only inhabits parts of New Zealand. Despite its current la...
Sphenodontia - Wikipedia
Testudines
Turtles are reptiles of the order Chelonii or Testudines characterised by a special bony or cartilaginous shell developed from their ribs and acting as a shield. Turtle may refer to the chelonian ord...
Testudines - Wikipedia
Evolution of birds
The evolution of birds is thought to have begun in the Jurassic Period, with the earliest birds derived from a clade of theropoda dinosaurs named Paraves. Birds are categorized as a biological class, ...
Evolution of birds - Wikipedia
Evolutionary history of life
The evolutionary history of life on Earth traces the processes by which living and fossil organisms have evolved since life on the planet first originated until the present day. Earth formed about 4.5...
Crocodilia
The Crocodilia (or Crocodylia) are an order of large, predatory, semiaquatic reptiles. They appeared 83.5 million years ago in the Late Cretaceous period (Campanian stage) and are the closest living r...
Crocodilia - Wikipedia