Reptiles are animals in the (Linnaean Linnaean taxonomy is a term for rank-based classification of organisms, in general. That is, taxonomy in the traditional sense of the word: rank-based scientific classification, This term is especially used as opposed to other ways of categorizing organisms, like cladistics and phenetics. It is attributed to Linnaeus, although he neither invented) class Reptilia. They are characterized by breathing air, laying tough-shelled amniotic eggs The amniotes are a group of tetrapod vertebrates that have a terrestrially adapted egg. They currently include mammals (synapsids), and sauropsids (reptiles and birds), as well as their fossil ancestors. Amniote embryos, whether laid as eggs or carried by the female, are protected and aided by several extensive membranes. In eutherian mammals (, and having skin covered in scales In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran (butterfly and moth) species, scales are plates on the surface of the insect wing, and provide coloration. Scales are quite common and have evolved multiple times with varying structure and function and/or scutes A scute or scutum is a bony external plate or scale, as on the shell of a turtle, the skin of crocodilians, or the feet of some birds. Reptiles are classically viewed as having a "cold-blooded Cold-blooded is a loose layman's term often used to refer to animals that do not use their metabolism to maintain body temperature. It is typically associated with at least one of three different thermophysiological characteristics:" metabolism. They are tetrapods Tetrapods are vertebrate animals having four limbs. Amphibians, reptiles, birds, and mammals are all tetrapods, and even the limbless snakes are tetrapods by descent. The earliest tetrapods radiated from the Sarcopterygii, or lobe-finned fish (either having four limbs or being descended from four-limbed ancestors). Modern reptiles inhabit every continent A continent is one of several large landmasses on Earth. They are generally identified by convention rather than any strict criteria, with seven regions commonly regarded as continents – they are : Asia, Africa, North America, South America, Antarctica, Europe, and Australia with the exception of Antarctica Antarctica (pronounced /ænˈtɑrktɪkə/ ) is Earth's southernmost continent, underlying the South Pole. It is situated in the Antarctic region of the southern hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean. At 14.0 million km2 (5.4 million sq mi), it is the fifth-largest continent in area after, and four living orders The Latin suffix -formes meaning "having the form of" is used for the scientific name of orders of birds and fishes, but not for those of mammals and invertebrates are currently recognized:
- Crocodilia Crocodilia is an order of large reptiles that appeared about 84 million years ago in the late Cretaceous Period (Campanian stage). They are the closest living relatives of birds, as the two groups are the only known survivors of the Archosauria. Members of the crocodilian total group, the clade Crurotarsi, appeared about 220 million years ago in (crocodiles A crocodile is any species belonging to the family Crocodylidae . The term can also be used more loosely to include all members of the order Crocodilia: i.e. the true crocodiles, the alligators and caimans (family Alligatoridae) and the gharials (family Gavialidae), or even the Crocodylomorpha which includes prehistoric crocodile relatives and, gavials The gharial (Gavialis gangeticus), sometimes called the Indian gavial or gavial, is one of two surviving members of the family Gavialidae, a long-established group of crocodile-like reptiles with long, narrow jaws. It is one of the three crocodilians found in India, the others being the Mugger crocodile and the Saltwater crocodile, caimans, and alligators An alligator is a crocodilian in the genus Alligator of the family Alligatoridae. There are two extant alligator species: the American alligator and the Chinese alligator (Alligator sinensis)): 23 species
- Sphenodontia Sphenodontia is an order of lizard-like reptiles that includes only one living genus, the tuatara . Despite its current lack of diversity, the Sphenodontia at one time included a wide array of genera in several families, and represents a lineage stretching back to the Mesozoic Era (tuataras The tuatara is a reptile endemic to New Zealand which, though it resembles most lizards, is actually part of a distinct lineage, order Sphenodontia. The two species of tuatara are the only surviving members of its order, which flourished around 200 million years ago. Their most recent common ancestor with any other extant group is with the from New Zealand New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses , and numerous smaller islands, most notably Stewart Island/Rakiura and the Chatham Islands. The indigenous Māori language name for New Zealand is Aotearoa, commonly translated as The Land of the Long White Cloud. The Realm of New Zealand also): 2 species
- Squamata Squamata, or the scaled reptiles, is the largest recent order of reptiles, including lizards and snakes. Members of the order are distinguished by their skins, which bear horny scales or shields. They also possess movable quadrate bones, making it possible to move the upper jaw relative to the braincase. This is particularly visible in snakes, (lizards Lizards are a very large and widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains. The group, traditionally recognized as the suborder Lacertilia, is defined as all extant members of the Lepidosauria , which are neither sphenodonts (i.e., tuatara) nor, snakes Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with many more joints than their lizard ancestors,, and worm lizards The Amphisbaenia are a usually legless suborder of squamates closely related to lizards and snakes. As many species possess a pink body coloration and scales arranged in rings, they have a superficial resemblance to earthworms. They are very poorly understood, due to their burrowing lifestyle and general rarity. Most species are found in Africa): approximately 7,900 species
- Testudines Turtles are reptiles of the order Testudines , characterised by a special bony or cartilaginous shell developed from their ribs that acts as a shield. "Turtle" may either refer to the Testudines as a whole, or to particular Testudines which make up a form taxon that is not monophyletic—see also sea turtle, terrapin, tortoise, and the (turtles Turtles are reptiles of the order Testudines , characterised by a special bony or cartilaginous shell developed from their ribs that acts as a shield. "Turtle" may either refer to the Testudines as a whole, or to particular Testudines which make up a form taxon that is not monophyletic—see also sea turtle, terrapin, tortoise, and the and tortoises Tortoises or land turtles are land-dwelling reptiles of the family of Testudinidae, order Testudines. Like their marine cousins, the sea turtles, tortoises are shielded from predators by a shell. The top part of the shell is the carapace, the underside is the plastron, and the two are connected by the bridge. The tortoise has both an endoskeleton): approximately 300 species
The majority of reptile species are oviparous In most birds, reptiles, insects, fish, and two types of mammals an egg (Latin, ovum) is the zygote, resulting from fertilization of the ovum. To enable incubation the egg is usually kept within a favourable temperature range as it nourishes and protects the growing embryo. When the embryo is adequately developed it breaks out of the egg in the (egg-laying), although certain species of squamates are capable of giving live birth. This is achieved by either ovoviviparity Ovoviviparity, ovovivipary, or ovivipary, is a mode of reproduction in animals in which embryos develop inside eggs that are retained within the mother's body until they are ready to hatch. Ovoviviparous animals are similar to viviparous species in that there is internal fertilization and the young are born live, but differ in that there is no (egg retention) or viviparity Vivipary has two different meanings. In animals, it means reproduction inside the body of the mother; that is, live birth . In plants, it means reproduction via embryos, such as spores or buds, that develop from the outset without interruption (as opposed to germinating externally from a seed) (birth of offspring without the development of calcified Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth most abundant element by mass in the Earth's crust. Calcium is also the fifth most abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, eggs). Many of the viviparous species feed their fetuses A fetus Pronounced Fee-tus is a developing mammal or other viviparous vertebrate after the embryonic stage and before birth through various forms of placenta The placenta is an organ that connects the developing fetus to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother's blood supply. Placentas are a defining characteristic of eutherian or "placental" mammals, but are also found in some snakes and lizards with varying levels of development up to analogous to those of mammals Mammals are a class of vertebrate, air-breathing animals whose females are characterized by the possession of mammary glands while both males and females are characterized by hair and/or fur, three middle ear bones used in hearing, and a neocortex region in the brain. Some mammals have sweat glands, but most do not, with some providing initial care for their hatchlings. Extant reptiles range in size from a tiny gecko, Sphaerodactylus ariasae Sphaerodactylus ariasae, the Jaragua Sphaero or dwarf gecko, is a very small Gekkonidae species in the Sphaerodactylus genus. It is one of the world's two smallest known reptiles . The Jaragua Sphaero measures 16-18 mm from the snout to the base of the tail and can fit on a US 25-cent coin. Its range is believed to be limited to Jaragua National, that grows to only 1.6 cm (0.6 in) to the saltwater crocodile The saltwater or estuarine crocodile is the largest of all living reptiles. It is found in suitable habitats in Northern Australia, the eastern coast of India and parts of Southeast Asia, Crocodylus porosus, that may reach 6 m in length and weigh over 1,000 kg. The science dealing with reptiles is called herpetology Herpetology is the branch of zoology concerned with the study of amphibians and of reptiles (including snakes, lizards, amphisbaenids, turtles, terrapins, tortoises, crocodilians, and the tuataras).
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Classification
Fri, 16 Jul 2010 22:16:03 GMT+00:00
7Online WSVN-TV The reptile grabbed and killed Adriana Salcedo's Jack Russell Terrier named Lucas, as her uncle walked him near a Coral Gables canal near Tarragona Drive, ...
