This clade is known as the "Tetrapods." Amniotes evolved during the late Paleozoic era.The characteristic that sets amniotes apart from other tetrapods is that amniotes lay eggs that are well-adapted to survive in a terrestrial environment. This group includes warm-blooded birds and scaly cold-blooded reptiles. Reptiles are cold-blooded, air-breathing vertebrates that have skin covered in scales as opposed to hair or feathers. all tetrapods.... breath air w/ lungs. Reptiles are tetrapods. reptiles, birds, mammals. Even aquatic reptiles return to … Amniotes (Amniota) are a group of tetrapods that includes birds, reptiles, and mammals. Reptiles – these are amniotes with thick skin and bony epidermal scales whose eggs have a mineralised shell. Contains membranes that protect the embryo. Modern Classification of Birds. According to modern classification, birds are part of the group Aves. Polytomy: When an ancestral branch has just two descendants, we call that splitting pattern a dichotomy. Reptiles are tetrapod animals in the class Reptilia / r ɛ p ˈ t ɪ l i ə /, a paraphyletic grouping comprising all amniotes except synapsids (mammals and their extinct relatives) and birds.Properly, reptiles and birds are grouped together in the monophyletic group known as sauropsids.The class Reptilia comprises turtles, crocodilians, snakes, amphisbaenians, … Tetrapods include all land-living vertebrates, such as frogs, turtles, hawks, and lions. The origin of tetrapods. Amniotic egg. The word "tetrapod" means "four feet" and includes all species alive today that have four feet — but this group also includes many animals that don't have four feet.That's because the group includes all the organisms (living and extinct) that descended from the last common ancestor of amphibians, reptiles, and mammals.So, for example, the … Limbless reptiles (snakes and other squamates) have vestigial limbs and, as with caecilians, are classified as tetrapods because they are descended from four-limbed ancestors. Most reptiles are tetrapods with two pairs of limbs, and they are exclusively terrestrial and do not have an aquatic larval stage. Reptiles are land-dwelling tetrapods that have scales and lay amniotic eggs. -reptiles-birds-mammals. Adaptations to dry terrestrial environments-waterproof skin ... all tetrapods are ECTOthermic except... mammalia & aves. Amphibians, reptiles (including dinosaurs and birds) and mammals are the major groups of the Tetrapoda. Reptiles lay on land eggs enclosed in shells. More than 10000 species of reptiles are known to live on earth with the first reptiles observed about 312 million years ago. Modern reptiles are divided into four orders based on their physical appearance. Amphibians, reptiles, dinosaurs, birds and mammals … birds: internal fert.-cloacas-no … Tetrapod, (superclass Tetrapoda), a superclass of animals that includes all limbed vertebrates (backboned animals) constituting the classes Amphibia (amphibians), Reptilia (reptiles), Aves (birds), Mammalia (mammals), and their direct ancestors … A group of tetrapods whose living members are the reptiles, including birds, and mammals. Amniotes – these are tetrapods whose embryo grows inside a waterproof membrane called an amnion, which enables life outside of the water. Derived characteristics of amniotes - Relatively impermeable skin - Ability to use the rib cage to ventilate the _____ - … Reptiles are ‘tetrapods’ (vertebrate animals that have four feet, legs or leg like appendages) and amniotes, animals whose embryos are surrounded by an amniotic membrane and members of the class Sauropsida. Amniote Clade. % Understanding that reptiles are a monophyletic group containing birds helped us find out that feathers evolved from scales, which were present in other reptiles but are absent in amphibians. This group is subdivided into two subgroups: Palaeognathae and Neognathae. However, the modern definition of reptiles generally refers to tetrapods such as crocodiles, lizards, turtles, and tuataras.