Concept
Tetrapod
Related concepts (64)
Amniote
Amniotes belong to the clade Amniota, a clade of tetrapod vertebrates that comprises sauropsids (including all reptiles and birds) and synapsids (including mammals and mammal ancestors like "pelycosaurs" and therapsids). They are distinguished from the other living tetrapod clade—the lissamphibians—by the development of three extraembryonic membranes (amnion for embryoic protection, chorion for gas exchange, and allantois for metabolic waste disposal or storage), thicker and more keratinized skin, and costal respiration (breathing by expanding/constricting the rib cage).
Snake
Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes (s3r'pEntiːz). Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more joints than their lizard ancestors, enabling them to swallow prey much larger than their heads (cranial kinesis). To accommodate their narrow bodies, snakes' paired organs (such as kidneys) appear one in front of the other instead of side by side, and most have only one functional lung.
Tuatara
Tuatara (Sphenodon punctatus) are reptiles endemic to New Zealand. Despite their close resemblance to lizards, they are part of a distinct lineage, the order Rhynchocephalia. The name tuatara is derived from the Māori language and means "peaks on the back". The single extant species of tuatara is the only surviving member of its order. Rhynchocephalians originated during the Triassic (~250 million years ago), reached worldwide distribution and peak diversity during the Jurassic and, with the exception of tuatara, were extinct by 60 million years ago.
Vertebrate
Vertebrates (ˈvɜrtəbrɪts,_-ˌbreɪts) are animals with spinal cords and bony or cartilaginous backbones, including all mammals, birds, reptiles, amphibians and fish. The vertebrates consist of all the taxa within the subphylum Vertebrata (ˌvɜrtəˈbreɪtə) (chordates with backbones) and represent the overwhelming majority of the phylum Chordata, with currently about 69,963 species described.
Turtle
Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked turtles), which differ in the way the head retracts. There are 360 living and recently extinct species of turtles, including land-dwelling tortoises and freshwater terrapins. They are found on most continents, some islands and, in the case of sea turtles, much of the ocean.
Frog
A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ἀνούρα, literally without tail in Ancient Greek). The oldest fossil "proto-frog" Triadobatrachus is known from the Early Triassic of Madagascar, but molecular clock dating suggests their split from other amphibians may extend further back to the Permian, 265 million years ago. Frogs are widely distributed, ranging from the tropics to subarctic regions, but the greatest concentration of species diversity is in tropical rainforest.
Coelacanth
Coelacanths (ˈsiːləkænθ ) (order Coelacanthiformes) are an ancient group of lobe-finned fish (Sarcopterygii) in the class Actinistia. As sarcopterygians, they are more closely related to lungfish and tetrapods (which includes amphibians, reptiles, birds and mammals) than to ray-finned fish. Well-represented in both freshwater and marine fossils since the Devonian, they are now represented by only two extant marine species in the genus Latimeria: the West Indian Ocean coelacanth (Latimeria chalumnae), primarily found near the Comoro Islands off the east coast of Africa, and the Indonesian coelacanth (Latimeria menadoensis).
Anapsid
An anapsid is an amniote whose skull lacks one or more skull openings (fenestra, or fossae) near the temples. Traditionally, the Anapsida are the most primitive subclass of amniotes, the ancestral stock from which Synapsida and Diapsida evolved, making anapsids paraphyletic. It is however doubtful that all anapsids lack temporal fenestra as a primitive trait, and that all the groups traditionally seen as anapsids truly lacked fenestra.
Salamander
Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All ten extant salamander families are grouped together under the order Urodela from the group Caudata. Salamander diversity is highest in eastern North America, especially in the Appalachian Mountains; most species are found in the Holarctic realm, with some species present in the Neotropical realm.
Paleontology
Paleontology (ˌpeɪliɒnˈtɒlədʒi,ˌpæli-,-ən-), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossils to classify organisms and study their interactions with each other and their environments (their paleoecology). Paleontological observations have been documented as far back as the 5th century BC.