What are Cotylosaurs?

Definition of cotylosaur : any of an order (Cotylosauria) of extinct primitive reptiles of the Carboniferous to Triassic with short legs and massive bodies that were probably the earliest truly terrestrial vertebrate animals.

Where did the Cotylosauria live?

Captorhinidae (also known as cotylosaurs) is an extinct family of primitive reptiles, known from the late Carboniferous to the Late Permian. They had a cosmopolitan distribution across Pangea.

What are stem reptiles?

Stem reptiles (aka Captorhinids or Cotylosaurs) are primitive anapsids that led to the reptiles (including dinosaurs and turtles), birds, and mammals .

Are Therapsids reptiles?

therapsid, any member of a major order (Therapsida) of reptiles of Permian and Triassic time (from 299 million to 200 million years ago). Therapsids were the stock that gave rise to mammals.

What did Sauropsids evolved into?

Sauropsids were amniotes that evolved into reptiles, dinosaurs, and birds. The two groups of amniotes differed in their skulls. The earliest known reptile, pictured in Figure below, dates back about 315 million years.

Why birds are reptiles?

Reptiles are vertebrates that have scales on at least some part of their body, leathery or hard-shelled eggs, and share a number of other features. Snakes, lizards, turtles, crocodilians, and birds are reptiles. Like all vertebrates, reptiles have bony skeletons that support their bodies.

What is the meaning of synapsids?

Definition of synapsid : any of a subclass (Synapsida) of terrestrial vertebrates (such as the pelycosaurs and therapsids) having a single pair of lateral temporal skull openings. Note: Traditional classifications typically consider synapsids to be mammal-like, extinct reptiles ancestral to mammals.

What is the difference between therapsids and synapsids?

The synapsids are traditionally divided for convenience, into therapsids, an advanced group of synapsids and the branch within which mammals evolved, and stem mammals, (previously known as pelycosaurs), comprising the other six more primitive families of synapsids.

What do therapsids do?

Therapsids were the stock that gave rise to mammals. As early as the preceding Carboniferous Period (from 359 million to 299 million years ago), there appeared a distinct evolutionary line, beginning with the archaic mammal ancestors, order Pelycosauria, and leading toward mammals.

What are synapsids and sauropsids?

Synapsids include all mammals and therapsids, mammal-like reptiles, from which mammals evolved. Sauropsids, which are divided into the anapsids and diapsids, include reptiles and birds.

What is the difference between sauropsids and synapsids?

Synapsids include all mammals, including extinct mammalian species. Synapsids also include therapsids, which were mammal-like reptiles from which mammals evolved. Sauropsids include reptiles and birds, and can be further divided into anapsids and diapsids.

Do reptiles lay eggs?

Both amphibians and reptiles come from eggs, but amphibian eggs need to stay moist or wet as they develop. Most amphibian eggs are laid in water. Reptile eggs need to stay dry, and all reptiles lay eggs on land, often burying them.