Turtles are reptiles Reptiles, or members of the class Reptilia, are air-breathing, generally "cold-blooded" (poikilothermic) amniotes whose skin is usually covered in scales or scutes. They are tetrapods (either having four limbs or being descended from four-limbed ancestors) and lay amniotic eggs, in which the embryo is surrounded by a membrane called the of the order 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 Testudines (the crown group A crown group is the smallest monophyletic group, or "clade", to contain the last common ancestor of all extant members, and all of that ancestor's descendants. Extinct organisms can still be part of a crown group: for instance, the extinct dodo is still descended from the last common ancestor of all living birds, so falls within the of the superorder 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 Chelonia), characterised by a special bony Bones are rigid organs that form part of the endoskeleton of vertebrates. They function to move, support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue. Because bones come in a variety of shapes and have a complex internal and external structure or cartilaginous Cartilage is a stiff yet flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs. It is not as hard and rigid as bone but is stiffer and less flexible than muscle shell An exoskeleton is an external skeleton that supports and protects an animal's body, in contrast to the internal skeleton of, for example, a human. Some animals, such as the tortoise, have both an endoskeleton and an exoskeleton. In popular usage, many of the larger kinds of exoskeletons are known as "shells" developed from their ribs In vertebrate anatomy, ribs are the long curved bones which form the ribcage. In most vertebrates, ribs surround the chest (Greek:θώραξ, Latin thorax) they enable lungs to expand by expanding the chest, they also protect the lungs, heart, and other internal organs of the thorax. In some animals, especially snakes, ribs may provide support and that acts as a shield A shield is a type of personal armor, meant to intercept attacks, either by stopping projectiles such as arrows or by glancing a blow to the side of the shield-user. Shields vary greatly in size, ranging from large shields that protect the user's entire body to small shields that are mostly for use in hand-to-hand combat. Shields also vary a great. "Turtle" may either refer to the Testudines as a whole, or to particular Testudines which make up a form taxon In general taxonomy, it is a kind of wastebasket taxon, either a taxon that is not a natural group but united by shared plesiomorphies, or a presumably artificial group of organisms whose true relationships are not known, being obscured by ecomorphological similarity. Well-known form taxa of this kind include "ducks", "fish", & that is not monophyletic In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it consists of an ancestor and all its descendants. The term is synonymous with the uncommon term holophyly. It is contrasted with the terms paraphyly, which is a taxon consisting of an ancestor and some of its descendants, and polyphyly, which is a taxon—see also sea turtle The superfamily Chelonioidea has a worldwide distribution; sea turtles can be found in all oceans except for the polar regions.[citation needed] Some species travel between oceans. The Flatback turtle is found solely on the northern coast of Australia, terrapin The diamondback terrapin belongs to the order Testudines along with all other extant turtles. Malaclemys terrapin is the only member of the genus, and is closely related to large genus of North American map turtles, Graptemys. Malaclemys has been divided into seven different subspecies, but these divisions are generally not supported by molecular, tortoise 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, and the discussion below.
The order Testudines includes both extant (living) and extinct In biology and ecology, extinction is the end of an organism or group of taxa. The moment of extinction is generally considered to be the death of the last individual of that species . Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena species. The earliest known turtles date from 215 million One million or one thousand thousand, is the natural number following 999,999 and preceding 1,000,001. The name is derived from Italian, where mille was 1,000, and 1,000,000 became milione, "a large thousand"[citation needed] years ago,[2] making turtles one of the oldest reptile groups and a more ancient group than 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 and 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,. About 300 species There are many definitions of what kind of unit a species is . A common definition is that of a group of organisms capable of interbreeding and producing fertile offspring of both genders, and separated from other such groups with which interbreeding does not (normally) happen. Other definitions may focus on similarity of DNA or morphology. Some are alive today,[citation needed] and some are highly endangered An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters. Also it could mean that due to deforestation there may be a lack of food and/or water. The International Union for Conservation of Nature has calculated the.[3]
Like other reptiles, turtles are ectotherms Ectothermic, from the Greek ectos, "outside" and therme, "heat," refers to organisms that control body temperature through external means. As a result, organisms are dependent on environmental heat sources and have relatively low metabolic rates. For example, many reptiles regulate their body temperature by basking in the sun—varying their internal temperature according to the ambient environment, commonly called cold-blooded A poikilotherm is an animal whose internal temperature varies along with that of the ambient environmental temperature. Most, but not all, ectotherms are poikilothermic. The opposite of poikilothermy is homeothermy, referring to animals that maintain a constant body temperature. The term is used as a more exact description of the vernacular ". However, leatherback sea turtle The leatherback turtle is the largest of all living sea turtles and the fourth largest modern reptile behind three crocodilians. It is the only living species in the genus Dermochelys. It can easily be differentiated from other modern sea turtles by its lack of a bony shell. Instead, its carapace is covered by skin and oily flesh. Dermochelys have noticeably higher body temperature than surrounding water because of their high metabolic rate.
Like other amniotes The amniotes are a group of tetrapod vertebrates that have a terrestrially adapted egg. They currently include mammals , 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 (such as humans) (reptiles, dinosaurs, birds, and mammals), they breathe air and do not lay eggs underwater, although many species live in or around water. The largest turtles are aquatic.
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Indiana Daily Student
Tina Fey, Ninja Turtles and 'N Sync graced the IU Auditorium with their presence Wednesday as students took the stage to practice ...
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Noelle and Darwinia are two adult female leatherback . turtles. that nest in Gabon, Western Central Africa. The research team has fitted each . turtle. with a small satellite tracking device, which enables the scientists to monitor their ...
