|
Amphisbaenians
Amphisbaenia (called amphisbaenians or worm lizards) is a group of usually legless squamates, comprising over 200 extant species. Amphisbaenians are characterized by their long bodies, the reduction or loss of the limbs, and rudimentary eyes. As many species have a pink body and scales arranged in rings, they have a superficial resemblance to earthworms. While the genus '' Bipes'' retains forelimbs, all other genera are limbless. Although superficially similar to the snakes and blind lizards, recent phylogenetic studies suggest that they are most closely related to wall lizards of the family Lacertidae. Amphisbaenians are widely distributed, occurring in North America, Europe, Africa, South America, Western Asia and the Caribbean. Most species are less than long. Description 200px, left, Close-up of the head of'' Rhineura'' Despite a superficial resemblance to some primitive snakes, amphisbaenians have many unique features that distinguish them from other reptiles. Internally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphisbaenia 1
Amphisbaenia (called amphisbaenians or worm lizards) is a group of usually legless squamates, comprising over 200 extant species. Amphisbaenians are characterized by their long bodies, the reduction or loss of the limbs, and rudimentary eyes. As many species have a pink body and scales arranged in rings, they have a superficial resemblance to earthworms. While the genus '' Bipes'' retains forelimbs, all other genera are limbless. Although superficially similar to the snakes and blind lizards, recent phylogenetic studies suggest that they are most closely related to wall lizards of the family Lacertidae. Amphisbaenians are widely distributed, occurring in North America, Europe, Africa, South America, Western Asia and the Caribbean. Most species are less than long. Description 200px, left, Close-up of the head of'' Rhineura'' Despite a superficial resemblance to some primitive snakes, amphisbaenians have many unique features that distinguish them from other reptiles. Internal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Edward Gray
John Edward Gray, FRS (12 February 1800 – 7 March 1875) was a British zoologist. He was the elder brother of zoologist George Robert Gray and son of the pharmacologist and botanist Samuel Frederick Gray (1766–1828). The same is used for a zoological name. Gray was keeper of zoology at the British Museum in London from 1840 until Christmas 1874, before the natural history holdings were split off to the Natural History Museum. He published several catalogues of the museum collections that included comprehensive discussions of animal groups and descriptions of new species. He improved the zoological collections to make them amongst the best in the world. Biography Gray was born in Walsall, but his family soon moved to London, where Gray studied medicine. He assisted his father in writing ''The Natural Arrangement of British Plants'' (1821). After being blackballed by the Linnean Society of London, Gray shifted his interest from botany to zoology. He began his zoologica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphisbaenidae
The Amphisbaenidae (common name: worm lizards) are a family of amphisbaenians, a group of limbless vertebrates. Geographic range Amphisbaenids occur in South America, some Caribbean islands, Europe, and sub-Saharan Africa. Taxonomy One deep-branching and somewhat aberrant genus, ''Blanus'', is native to Europe, and may represent a distinct family. More recent sources indeed place it in the family Blanidae. Description Members of the family Amphisbaenidae are limbless, burrowing reptiles with carnivorous diets. As in other amphisbaenians, the body bears rings of scales, which gives amphisbaenids a worm-like appearance. The head is massively constructed and used for burrowing, with powerful jaws and large, recurved teeth used for seizing prey. Some species have a spade-like head, while others have a narrow keel on the head, and still others have a rounded skull. The eyes are highly reduced, while the ear bone, or stapes in the middle ear, is large and massive. Together with anot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bipedidae
Bipedidae is a family of amphisbaenians that includes the extant genus '' Bipes'' represented by three species from Baja California and the southern coast of Mexico and the extinct genus ''Anniealexandria'' represented by one species that lived in what is now Wyoming during the earliest Eocene around 55 million years ago. Phylogenetic analysis indicates that Bipedidae is most closely related to the family Blanidae, which includes the living genus ''Blanus ''Blanus'' is a genus of amphisbaenians found in the Mediterranean region of Europe and North Africa. Like other amphisbaenians, ''Blanus'' species are specialized for a subterranean existence, with long, slender bodies, reduced limbs, and rudim ...''. Bipedidae are very small usually ranging from 120 to 240 mm, and have large mole-like limbs that each include five claws. They have a short tail that does not regenerate if lost. They use their blunt head for burrowing by ramming it into the soil, and usually prey on arthropod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blanidae
''Blanus'' is a genus of amphisbaenians found in the Mediterranean region of Europe and North Africa. Like other amphisbaenians, ''Blanus'' species are specialized for a subterranean existence, with long, slender bodies, reduced limbs, and rudimentary eyes. Their skulls are powerfully constructed, allowing them to push through soil to create a burrow. Their jaws are well-developed, with large, recurved teeth and a pair of canine-like teeth in the upper jaw. Five extant species are currently known. The relationships of ''Blanus'' to other worm-lizards are not clear. The genus was formerly included in the Amphisbaenidae. More recent analyses suggest that blanids are more primitive, and are either related to '' Bipes'' or represent an even more ancient lineage. A number of fossils from Europe have been referred either to ''Blanus'' or to the Blanidae. Species The genus contains the following species:Blanus Wikispecies. * ''Blanus alexandri'' Sindaco, Kornilios, Sacchi & Lymbera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhineuridae
Rhineuridae is a family of amphisbaenians (commonly called worm lizards) that includes one living genus and species, ''Rhineura floridana'', as well as many extinct species belonging to both ''Rhineura'' and several extinct genera. The living ''R. floridana'' is found only in Georgia and Florida, but extinct species ranged across North America, some occurring as far west as Oregon. The family has a fossil record stretching back 60 million years to the Paleocene and was most diverse in the continental interior during the Eocene and Oligocene. Fossil record The fossil record of the Rhineuridae extends back almost to the Mesozoic, with the oldest rhineurid, '' Plesiorhineura tsentasai'', occurring in the Early Paleocene. ''Plesiorhineura'' is only known from a partial jaw, but it shares many features with modern rhineurids. Eocene rhineurids, such as ''Spathorhynchus fossorium'', are remarkably similar to the modern ''Rhineura'', suggesting very conservative evolution within the fami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blanus Skull By Nick Longrich
''Blanus'' is a genus of amphisbaenians found in the Mediterranean region of Europe and North Africa. Like other amphisbaenians, ''Blanus'' species are specialized for a subterranean existence, with long, slender bodies, reduced limbs, and rudimentary eyes. Their skulls are powerfully constructed, allowing them to push through soil to create a burrow. Their jaws are well-developed, with large, recurved teeth and a pair of canine-like teeth in the upper jaw. Five extant species are currently known. The relationships of ''Blanus'' to other worm-lizards are not clear. The genus was formerly included in the Amphisbaenidae. More recent analyses suggest that blanids are more primitive, and are either related to '' Bipes'' or represent an even more ancient lineage. A number of fossils from Europe have been referred either to ''Blanus'' or to the Blanidae. Species The genus contains the following species:Blanus Wikispecies. * '' Blanus alexandri'' Sindaco, Kornilios, Sacchi & Lym ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viviparity
Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the mother. The term 'viviparity' and its adjective form 'viviparous' derive from the Latin ''vivus'' meaning "living" and ''pario'' meaning "give birth to". Reproductive mode Five modes of reproduction have been differentiated in animals based on relations between zygote and parents. The five include two nonviviparous modes: ovuliparity, with external fertilisation, and oviparity, with internal fertilisation. In the latter, the female lays zygotes as eggs with a large vitellus, yolk; this occurs in all birds, most reptiles, and some fishes. These modes are distinguished from viviparity, which covers all the modes that result in live birth: *Histotrophic viviparity: the zygotes develop in the female's oviducts, but find their nutrients b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Chamber Of Eyeball
The anterior chamber (Optometric Abbreviations#AC, AC) is the aqueous humor-filled space inside the human eye, eye between the iris (anatomy), iris and the cornea's innermost surface, the Corneal endothelium, endothelium. Hyphema, Uveitis, anterior uveitis and glaucoma are three main pathologies in this area. In hyphema, blood fills the anterior chamber as a result of a hemorrhage, most commonly after a blunt eye injury. Anterior uveitis is an inflammatory process affecting the iris (anatomy), iris and ciliary body, with resulting inflammatory signs in the anterior chamber. In glaucoma, blockage of the trabecular meshwork prevents the normal outflow of aqueous humour, resulting in increased intraocular pressure, progressive damage to the optic nerve head, and eventually blindness. The depth of the anterior chamber of the eye varies between 1.5 and 4.0 mm, averaging 3.0 mm. It tends to become shallower at older age and in eyes with Far-sightedness, hypermetropia (far sight ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphisbaena
The amphisbaena (, , or , plural: amphisbaenae; grc, ἀμφίσβαινα) is a mythological, ant-eating serpent with a head at each end. The creature is alternatively called the amphisbaina, amphisbene, amphisboena, amphisbona, amphista, amfivena, amphivena, or anphivena (the last two being feminine), and is also known as the "Mother of Ants". Its name comes from the Greek words ', meaning "both ways", and ', meaning "to go". Mythology According to Greek mythology, the amphisbaena was spawned from the blood that dripped from the Gorgon Medusa's head as Perseus flew over the Libyan Desert with her head in his hand, after which Cato's army then encountered it along with other serpents on the march. Amphisbaena fed on the corpses left behind. The amphisbaena has been referred to by various poets such as Nicander, John Milton, Alexander Pope, Percy Bysshe Shelley, Alfred Tennyson, Aimé Césaire, A. E. Housman and Allen Mandelbaum; as a mythological and legendary creature, it h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autotomy
Autotomy (from the Greek language, Greek ''auto-'', "self-" and ''tome'', "severing", wikt:αὐτοτομία, αὐτοτομία) or self-amputation, is the behaviour whereby an animal sheds or discards one or more of its own appendages, usually as a self-preservation, self-defense mechanism to elude a predation, predator's grasp or to distract the predator and thereby allow escape. Some animals have the ability to regeneration (biology), regenerate the lost body part later. Autotomy has multiple evolutionary origins and is thought to have evolved at least nine times independently in animalia. The term was coined in 1883 by Léon Fredericq, Leon Fredericq. Vertebrates Reptiles and amphibians Some lizards, salamanders and tuatara when caught by the tail will shed part of it in attempting to escape. In many species the detached tail will continue to wriggle, creating a deceptive sense of continued struggle, and distracting the predator's attention from the fleeing prey animal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.JPG "Click for more on -> Amphisbaenidae")
