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Lepidotrichia
In a zoological context, spines are hard, needle-like anatomical structures found in both vertebrate and invertebrate species. The spines of most spiny mammals are modified hairs, with a spongy center covered in a thick, hard layer of keratin and a sharp, sometimes barbed tip. Occurrence Mammals Spines in mammals include the prickles of hedgehogs, and among rodents, the quills of porcupines (of both the New World and the Old), as well as the prickly fur of spiny mice, spiny pocket mice, and of species of spiny rat. They are also found on afrotherian tenrecs of the family Tenrecinae (hedgehog and streaked tenrecs), marsupial spiny bandicoots, and on echidnas (a monotreme). An ancient synapsid, ''Dimetrodon'', had extremely long spines on its backbone that were joined together with a web of skin that formed a sail-like structure. Many mammalian species, like cats and fossas, also have penile spines. The Mesozoic eutriconodont mammal '' Spinolestes'' already displayed sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Fin
Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only by muscles. Fish fins are distinctive anatomical features with varying structures among different clades: in ray-finned fish (Actinopterygii), fins are mainly composed of bony spines or rays covered by a thin stretch of scaleless skin; in lobe-finned fish ( Sarcopterygii) such as coelacanths and lungfish, fins are short rays based around a muscular central bud supported by jointed bones; in cartilaginous fish ( Chondrichthyes) and jawless fish ( Agnatha), fins are fleshy " flippers" supported by a cartilaginous skeleton. Fins at different locations of the fish body serve different purposes, and are divided into two groups: the midsagittal ''unpaired fins'' and the more laterally located ''paired fins''. Unpaired fins are p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebrate
Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebrata with some 65,000 species, by far the largest ranked grouping in the phylum Chordata. The vertebrates include mammals, birds, amphibians, and various classes of fish and reptiles. The fish include the jawless Agnatha, and the jawed Gnathostomata. The jawed fish include both the Chondrichthyes, cartilaginous fish and the Osteichthyes, bony fish. Bony fish include the Sarcopterygii, lobe-finned fish, which gave rise to the tetrapods, the animals with four limbs. Despite their success, vertebrates still only make up less than five percent of all described animal species. The first vertebrates appeared in the Cambrian explosion some 518 million years ago. Jawed vertebrates evolved in the Ordovician, followed by bony fishes in the Devonian. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echidna
Echidnas (), sometimes known as spiny anteaters, are quill-covered monotremes (egg-laying mammals) belonging to the Family (biology), family Tachyglossidae , living in Australia and New Guinea. The four Extant taxon, extant species of echidnas and the platypus are the only living mammals that lay eggs and the only surviving members of the order (biology), order Monotremata. The diet of some species consists of ants and termites, but they are not closely related to the American anteater, true anteaters or to Hedgehog, hedgehogs. Their young are called puggles. Echidnas evolved between 20 and 50 million years ago, descending from a platypus-like monotreme. This ancestor was aquatic, but echidnas adapted to life on land, where a single individual can move seven tons of soil each year, making them important for the environment. Etymology Echidnas are possibly named after Echidna (mythology), Echidna, a creature from Greek mythology who was half-woman, half-snake, as the anima ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bony Fish
Osteichthyes ( ; ), also known as osteichthyans or commonly referred to as the bony fish, is a Biodiversity, diverse clade of vertebrate animals that have endoskeletons primarily composed of bone tissue. They can be contrasted with the Chondrichthyes (cartilaginous fish) and the extinct placoderms and acanthodians, which have endoskeletons primarily composed of cartilage. The vast majority of extant taxon, extant fish are members of Osteichthyes, being an extremely diverse and abundant group consisting of 45 order (biology), orders, over 435 family (biology), families and 28,000 species. The group is divided into two main clades, the ray-finned fish (Actinopterygii, which makes up the vast majority of extant fish) and the lobe-finned fish (Sarcopterygii, which gave rise to all land vertebrates, i.e. tetrapods). The oldest known fossils of bony fish are about 425 million years old from the late Silurian, which are also transitional fossils showing a dentition, tooth pattern th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latimeria Chalumnae
The West Indian Ocean coelacanth (''Latimeria chalumnae'') (sometimes known as gombessa, African coelacanth, or simply coelacanth) is a Sarcopterygii, crossopterygian, one of two extant species of coelacanth, a rare order of vertebrates more closely related to lungfish and tetrapods than to the common ray-finned fishes. The other extant species is the Indonesian coelacanth (''L. menadoensis''). The West Indian Ocean coelacanth was historically known by fishermen around the Comoro Islands (where it is known as ''gombessa''), Madagascar, and Mozambique in the western Indian Ocean, but first scientifically recognised from a specimen collected in South Africa in 1938. This coelacanth was once thought to be evolutionarily conservative, but discoveries have shown initial morphological diversity. It has a vivid blue pigment, and is the better known of the two extant species. The species has been assessed as Critically endangered species, critically endangered on the IUCN Red List. Ana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barb Gonio 080526 9681 Ltn Pv
Barb or the BARBs or ''variation'' may refer to: People * Barb (name), a list of people and fictional characters with the given name or surname * Barb, a term used by fans of Nicki Minaj to refer to themselves * The Barbs, a band Places * Barb, Ontario, Canada * DeKalb, Illinois, USA; nicknamed ''Barb City'' Animals * Barb (feather), the branches issuing from the rachis of feathers * Barb (fish), common name for a range of freshwater fish * Barb horse, a breed from North Africa * Barb (pigeon), a breed of domestic pigeon * Australian Kelpie or barb, a breed of dog * The Barb (1863–1888), Australian Thoroughbred racehorse Implements * Barding or barb, a type of armor for horses * A backward-facing point on a fish hook or similar implement, rendering extraction from the victim's flesh more difficult * A type of pipe fitting called barb, used to connect hosing (the ridges face backward, making insertion easy and removal difficult) * Barb, a shortened version of barbitura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinolestes
''Spinolestes'' is an extinct mammal genus from the Early Cretaceous of Spain. A gobiconodontid eutriconodont, it is notable for the remarkable degree of preservation, offering profound insights to the biology of non-therian mammals.Thomas Martin, Jesús Marugán-Lobón, Romain Vullo, Hugo Martín-Abad, Zhe-Xi Luo & Angela D. Buscalioni (2015). A Cretaceous eutriconodont and integument evolution in early mammals. Nature 526, 380–384. doi:10.1038/nature14905 Description ''Spinolestes holotype, MCCMLH30000A', hails from Las Hoyas, Spain. The living animal was about 24 centimeters long and weighted somewhere between 50 and 70 grams. As a Konservat-Lagerstätten specimen, it is famous for being remarkably well preserved, including not only the skeleton but also multiple soft tissues like fur, skin, internal organs and ears (both external and internal), a rarity among Mesozoic mammals. Besides soft-tissues, ''Spinolestes'' is also remarkable for its xenarthrous vertebrae, converge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutriconodont
Eutriconodonta is an order (biology), order of early mammals. Eutriconodonts existed in Asia (including Insular India, pre-contact India), Africa, Europe, North America, North and South America during the Jurassic and the Cretaceous periods. The order was named by Kermack ''et al.'' in 1973 as a replacement name for the paraphyletic Triconodonta. Traditionally seen as the classical Mesozoic small mammalian insectivores, discoveries over the years have shown them to be among the best examples of the diversity of mammals in this time period, including a vast variety of bodyplans, ecological niches and locomotion methods. Classification "Triconodonta" had long been used as the name for an order of early mammals which were close relatives of the ancestors of all present-day mammals, characterized by molar teeth with three main cusps on a crown that were arranged in a row. The group originally included only the family Triconodontidae and taxa that were later assigned to the separate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penile Spines
Many mammalian species have developed keratinized penile spines along the glans or shaft, which may be involved in sexual selection. These spines have been described as being simple, single-pointed structures (macaques) or complex with two or three points per spine ( strepsirrhines). Penile spine morphology may be related to mating system. Non-human mammals Felines, especially domestic cats, are well known for having penile spines. Upon withdrawal of a cat's penis, the spines rake the walls of the female's vagina, which may serve as a trigger for ovulation. Many other felid species have penile spines, but they are relatively small in jaguars and pumas, and do not occur in margays. Penile spines in chimpanzees and mice are small surface projections made by the piling up of keratinized cell layers in the outermost skin surface.Hill, W.C.O. Note on the male external genitalia of the chimpanzee. ''Proc.Zool.Soc. Lond.'' 116, 129–132 (1946) They occur in wombats, koalas, spo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossa (animal)
The fossa (''Cryptoprocta ferox''; or ; ) is a slender, long-tailed, cat-like mammal that is endemic to Madagascar. It is a member of the carnivora, carnivoran family Eupleridae. The fossa is the largest mammalian carnivore on Madagascar and has been compared to a small cougar, as it has Convergent evolution, convergently evolved many cat-like features. Adults have a head-body length of and weigh between , with the males larger than the females. It has semi-retractable claws (meaning it can extend but not retract its claws fully) and flexible ankles that allow it to climb up and down trees head-first, and also support jumping from tree to tree. A larger relative of the species, ''Cryptoprocta spelea'', probably became extinct before 1400. The species is widespread, although population density, population densities are usually low. It is found solely in forested habitat, and actively hunts both by day and night. Over 50% of its diet consists of lemurs, the endemic primates f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
