Search results
Results from the WOW.Com Content Network
Synapsida[a] is one of the two major clades of vertebrate animals in the group Amniota, the other being the Sauropsida (which includes reptiles and birds). The synapsids were the dominant land animals in the late Paleozoic and early Mesozoic, but the only group that survived into the Cenozoic are mammals. [7]
Amphibians are ectothermic, anamniotic, four-limbed vertebrate animals that constitute the class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all tetrapods excluding the amniotes (tetrapods with an amniotic membrane, such as modern reptiles, birds and mammals).
Figure 1:In mammals, the quadrate and articular bones are small and part of the middle ear; the lower jaw consists only of dentary bone.. While living mammal species can be identified by the presence of milk-producing mammary glands in the females, other features are required when classifying fossils, because mammary glands and other soft-tissue features are not visible in fossils.
While reptiles and amphibians can be quite similar externally, the French zoologist Pierre André Latreille recognized the large physiological differences at the beginning of the 19th century and split the herptiles into two classes, giving the four familiar classes of tetrapods: amphibians, reptiles, birds and mammals. [30]
A mammal (from Latin mamma 'breast') [1] is a vertebrate animal of the class Mammalia (/ məˈmeɪli.ə /). Mammals are characterized by the presence of milk -producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three middle ear bones.
Class Amphibia (amphibians, some ancestral to the amniotes)—now a paraphyletic group; Class Synapsida (mammals and the extinct mammal-like reptiles) Class Sauropsida (reptiles and birds) While this traditional classification is orderly, most of the groups are paraphyletic, i.e. do not contain all descendants of the class's common ancestor. [46]
The term amniote comes from the amnion, which derives from Greek ἀμνίον (amnion), which denoted the membrane that surrounds a fetus. The term originally described a bowl in which the blood of sacrificed animals was caught, and derived from ἀμνός (amnos), meaning "lamb". [17]
Frog. This article is about the group of amphibians. For other uses, see Frog (disambiguation). A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura[1] (coming from the Ancient Greek ἀνούρα, literally 'without tail').