"adapted to a nocturnal way of life. Their spiny protection resembles that of the unrelated porcupines, which are rodents, and echidnas, a type of monotreme. The name ""hedgehog"" came into use around the year 1450, derived from the Middle English ""heyghoge"", from ""heyg"", ""hegge"" (""hedge""), because it frequents hedgerows, and ""hoge"", ""hogge"" (""hog""), from its piglike snout. Other names include ""urchin"", ""hedgepig"" and ""furze-pig"". The collective noun for a group of hedgehogs is ""array"". Hedgehogs are easily recognized by their spines, which are hollow hairs made stiff with keratin. Their spines are not poisonous or barbed and unlike the quills"
"Synapsid Synapsids (Greek, 'fused arch'), synonymous with theropsids (Greek, 'beast-face'), are a group of animals that includes mammals and every animal more closely related to mammals than to other living amniotes. They are easily separated from other amniotes by having a temporal fenestra, an opening low in the skull roof behind each eye, leaving a bony arch beneath each; this accounts for their name. Primitive synapsids are usually called pelycosaurs or pelycosaur-grade synapsids; more advanced mammal-like ones, therapsids. The non-mammalian members are described as mammal-like reptiles in classical systematics; they can also be called stem mammals or proto-mammals. Synapsids evolved"
"Archosaur Archosaurs are a group of diapsid amniotes whose living representatives consist of birds and crocodilians. This group also includes all extinct dinosaurs, extinct crocodilian relatives, and pterosaurs. Archosauria, the archosaur clade, is a crown group that includes the most recent common ancestor of living birds and crocodilians. It includes two main clades: Pseudosuchia, which includes crocodilians and their extinct relatives, and Avemetatarsalia, which includes birds and their extinct relatives (such as non-avian dinosaurs and pterosaurs). Archosaurs can be distinguished from other tetrapods on the basis of several synapomorphies, or shared characteristics, first found in a common ancestor. The simplest"
"an animal trying to keep up with the group; (10) warble - young animals establishing contact or coming close to an adult; (11) purr - close and pacific contact; (12) chirriar - pacific interaction of young ones during play. Perhaps the most important display is the behavior of breaking branches, which all members of the group carry out. Even infants break small branches (or twigs), letting them fall to the soil, but the most spectacular is the alpha male who chooses large, dry branches which he hits with his hands and feet in spectacular jumps, so that they fall. Usually"
"Arctoidea Arctoidea is an infraorder of mostly carnivorous mammals which include the extinct Hemicyonidae (dog-bears), and the extant Musteloidea (weasels, raccoons, skunks, red pandas), Pinnipedia (seals, sea lions), and Ursidae (bears), found in all continents from the Eocene, , to the present. Arctoids are caniforms, along with dogs (canids) and extinct bear dogs (Amphicyonidae). The earliest caniforms were superficially similar to martens, which are tree-dwelling mustelids. Together with feliforms, caniforms comprise the order Carnivora. Arctoidea was named by Flower (1869). It was reranked as the unranked clade Arctoidea by Hunt (2001), Hunt (2002) and Hunt (2002); it was reranked as"
"Collective noun In linguistics, a collective noun refers to a collection of things taken as a whole. Most collective nouns in everyday speech are mundane and ""not"" specific to just one kind, such as the word ""group"", which is applied to ""people"" in the phrase ""a group of people"", but is also applied to ""dogs"" in the phrase ""a group of dogs"". Other collective nouns ""are specific"" to one kind, especially terms of venery, which identify specific groups of animals. For example, ""pride"" as a term of venery always refers to lions, never to dogs or cows. Similarly, a group"
"groups of carnivores are usually called ""packs"", and in nature a herd is classically subject to predation from pack hunters. Special collective nouns may be used for particular taxa (for example a flock of geese, if not in flight, is sometimes called a ""gaggle"") but for theoretical discussions of behavioural ecology, the generic term ""herd"" can be used for all such kinds of assemblage. The word ""herd"", as a noun, can also refer to one who controls, possesses and has care for such groups of animals when they are domesticated. Examples of herds in this sense include shepherds (who tend"
"Herd A herd is a social group of certain animals of the same species, either wild or domestic. The form of collective animal behavior associated with this is referred to as ""herding"". The term ""herd"" is generally applied to mammals, and most particularly to the grazing ungulates that classically display this behaviour. Different terms are used for similar groupings in other species; in the case of birds, for example, the word is ""flocking"", but ""flock"" may also be used, in certain instances, for mammals, particularly sheep or goats. A group of quail is often referred to as a covey. Large"
"order Algae. For a long time thereafter sponges were assigned to a separate subkingdom, Parazoa (meaning ""beside the animals""). They are now classified as a paraphyletic phylum from which the higher animals have evolved. Cnidarians (Greek for ""nettle"") are distinguished by the presence of stinging cells, specialized cells that they use mainly for capturing prey. Cnidarians include corals, sea anemones, jellyfish and hydrozoans. They form a phylum containing over 10,000 species of animals found exclusively in aquatic (mainly marine) environments. Their bodies consist of mesoglea, a non-living jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell"
"Arachnid Arachnids () are a class (Arachnida) of joint-legged invertebrate animals (arthropods), in the subphylum Chelicerata. Almost all adult arachnids have eight legs, although the front pair of legs in some species has converted to a sensory function, while in other species, different appendages can grow large enough to take on the appearance of extra pairs of legs. The term is derived from the Greek word (""aráchnē""), from the myth of the hubristic human weaver Arachne who was turned into a spider. Spiders are the largest order in the class, which also includes scorpions, ticks, mites, harvestmen, and solifuges. Almost"
"Swarm behaviour Swarm behaviour, or swarming, is a collective behaviour exhibited by entities, particularly animals, of similar size which aggregate together, perhaps milling about the same spot or perhaps moving ""en masse"" or migrating in some direction. It is a highly interdisciplinary topic. As a term, ""swarming"" is applied particularly to insects, but can also be applied to any other entity or animal that exhibits swarm behaviour. The term ""flocking"" or ""murmuration"" can refer specifically to swarm behaviour in birds, ""herding"" to refer to swarm behaviour in tetrapods, and ""shoaling"" or ""schooling"" to refer to swarm behaviour in fish. Phytoplankton"
"Archaeoidea The Archaeoidea or archaeoids are a group of araneomorph spiders, formerly treated as a superfamily. The unity of the group is rejected , with former members being placed in the Araneoidea and Palpimanoidea. In 1984, Forster and Platnick reviewed spiders related to the archaeids. They created two new families, the Holarchaeidae and Pararchaeidae, which they grouped together with the Archaeidae and Mecysmaucheniidae, without giving them a formal name. One feature linking the four families is the way in which the front margin of the carapace is extended to encircle the base of the chelicerae. Forster and Platnick further suggested"
"and that there may be up to 600,000 in total. Arachnid Arachnids () are a class (Arachnida) of joint-legged invertebrate animals (arthropods), in the subphylum Chelicerata. Almost all adult arachnids have eight legs, although the front pair of legs in some species has converted to a sensory function, while in other species, different appendages can grow large enough to take on the appearance of extra pairs of legs. The term is derived from the Greek word (""aráchnē""), from the myth of the hubristic human weaver Arachne who was turned into a spider. Spiders are the largest order in the class,"
"words (), expressing the ""absence"" (this prefix is an alpha privative), and (), meaning ""animal tail"". It refers to the tailless character of these amphibians. About 88% of amphibian species are classified in the order Anura. These include around 4,810 species in 33 families, of which the Leptodactylidae (1,100 spp.), Hylidae (800 spp.) and Ranidae (750 spp.) are the richest in species. The use of the common names ""frog"" and ""toad"" has no taxonomic justification. From a classification perspective, all members of the order Anura are frogs, but only members of the family Bufonidae are considered ""true toads"". The use"
"Thyreophora Thyreophora (""shield bearers"", often known simply as ""armored dinosaurs"" - Greek: ""θυρεος"", thyreos, a large oblong shield, like a door and ""φορεω"", I carry) is a group of armored ornithischian dinosaurs that lived from the early Jurassic Period until the end of the Cretaceous. Thyreophorans are characterized by the presence of body armor lined up in longitudinal rows along the body. Primitive forms had simple, low, keeled scutes or osteoderms, whereas more derived forms developed more elaborate structures including spikes and plates. Most thyreophorans were herbivorous and had relatively small brains for their body size. Thyreophora includes various subgroups,"
"lighthearted, humorous or facetious collective nouns. Collective noun In linguistics, a collective noun refers to a collection of things taken as a whole. Most collective nouns in everyday speech are mundane and ""not"" specific to just one kind, such as the word ""group"", which is applied to ""people"" in the phrase ""a group of people"", but is also applied to ""dogs"" in the phrase ""a group of dogs"". Other collective nouns ""are specific"" to one kind, especially terms of venery, which identify specific groups of animals. For example, ""pride"" as a term of venery always refers to lions, never to"
"Lists of animals Animals are multicellular eukaryotic organisms that form the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million in total. Animals range in size from 8.5 millionths of a metre to long and have complex interactions with each other and their environments, forming intricate food webs. The study of animals is called"
"A group of vultures is called a kettle, committee or wake. The term ""kettle"" refers to vultures in flight, while ""committee"" refers to vultures resting on the ground or in trees. ""Wake"" is reserved for a group of vultures that are feeding. The word ""Geier"" (taken from the German language) does not have a precise meaning in ornithology; it is occasionally used to refer to a vulture in English, as in some poetry. The Old World vultures found in Africa, Asia, and Europe belong to the family Accipitridae, which also includes eagles, kites, buzzards, and hawks. Old World vultures find"
"Arthropod An arthropod (, from Greek ""arthron"", ""joint"" and ""pous"", ""foot"") is an invertebrate animal having an exoskeleton (external skeleton), a segmented body, and paired jointed appendages. Arthropods form the phylum Euarthropoda, which includes insects, arachnids, myriapods, and crustaceans. The term Arthropoda as originally proposed refers to a proposed grouping of Euarthropods and the phylum Onychophora. Arthropods are characterized by their jointed limbs and cuticle made of chitin, often mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. The rigid cuticle inhibits growth, so arthropods replace it periodically by moulting. Arthopods are"
"Procyonidae Procyonidae is a New World family of the order Carnivora. It comprises the raccoons, coatis, kinkajous, olingos, olinguitos, ringtails, and cacomistles. Procyonids inhabit a wide range of environments and are generally omnivorous. Procyonids are relatively small animals, with generally slender bodies and long tails (though the common raccoon tends to be bulky). Because of their general build, the Procyonidae are often popularly viewed as smaller cousins of the bear family. This is apparent in their German names: a raccoon is called a ""Waschbär"" (washing bear, as he ""washes"" his food before eating), a coati is a ""Nasenbär"" (nose-bear), while"
"Bird Birds, also known as Aves, are a group of endothermic vertebrates, characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight skeleton. Birds live worldwide and range in size from the bee hummingbird to the ostrich. They rank as the world's most numerically-successful class of tetrapods, with approximately ten thousand living species, more than half of these being passerines, sometimes known as perching birds. Birds have which are more or less developed depending on the species; the only known groups without wings are the extinct moa"
"superfamily Hominoidea: In terms of the common names on the right, this group consists of apes and humans and there is no single common name for all the members of the group. One remedy is to create a new common name, in this case ""hominoids"". Another possibility is to expand the use of one of the traditional names. For example, in his 2005 book, the vertebrate palaeontologist Benton wrote, ""The apes, Hominoidea, today include the gibbons and orang-utan ... the gorilla and chimpanzee ... and humans""; thereby Benton was using ""apes"" to mean ""hominoids"". In that case, the group heretofore"
"arches. Indeed, many authors have considered them so distinct as to warrant separation in a monotypic superorder of the Teleostei, under the name Cyclosquamata. However, monotypic taxa are generally avoided by modern taxonomists if not necessary, and in this case a distinct superorder seems indeed unwarranted: together with the equally dubious superorder ""Stenopterygii"", the grinners appear to be so closely related to some Protacanthopterygii to be included in that superorder. In particular, this group might be the sister taxon of the Salmoniformes (salmon, trout, and relatives). As an alternative, the superorders are sometimes united as an unranked clade named Euteleostei,"
"Acari Acari (or Acarina) are a taxon of arachnids that contains mites and ticks. The diversity of the Acari is extraordinary and its fossil history goes back to at least the early Devonian period. Acarologists (people who study Acari) have proposed a complex set of taxonomic ranks to classify mites. In most modern treatments, the Acari is considered a subclass of Arachnida and is composed of two or three superorders or orders: Acariformes (or Actinotrichida), Parasitiformes (or Anactinotrichida), and Opilioacariformes; the latter is often considered a subgroup within the Parasitiformes. The monophyly of the Acari is open to debate, and"
"Ferae The Ferae are a clade of mammals, consisting of the orders Carnivora (over 260 species, around the globe) and Pholidota (eight species of pangolins in tropical Africa and Asia). Pangolins do not exhibit morphological traits typically associated with carnivorans (wolves, cats, seals, and so on), and were thought to be the closest relatives of Xenarthra (armadillos and sloths), but DNA research conducted in the 2000s found the close relationship to carnivorans. Several extinct orders, relatives of the Pholidota, such as Creodonts, are members of Ferae as well. An alternate name, Ostentoria, has also been proposed for a grouping of"
"Argia Argia is a genus of damselflies of the family Coenagrionidae and of the subfamily Argiinae. It is a diverse genus which contains about 114 species and many more to be described. It is also the largest genus in Argiinae. They are found in the Western Hemisphere. They are commonly known as ""dancers"". Although the genus name comes from , dancers are quite active and alert damselflies. The bluer ""Argia"" species may be confused with ""Enallagma"" species. This genus of damselflies are known as dancers because of the distinctive jerky form of flight they use which contrasts with the straightforward"
"Eucarida Eucarida is a superorder of the Malacostraca, a class of the crustacean subphylum, comprising the decapods, krill, ""Amphionides"" and Angustidontida. They are characterised by having the carapace fused to all thoracic segments, and by the possession of stalked eyes. Eucarida is a diverse and abundant group, comprising the following four orders: The members of the Euphausiacea are commonly called krill and are all marine shrimp-like species whose pleopods (abdominal appendages) function as swimmerets. They swarm and mostly feed on plankton. This group is composed of only 90 species, some of which are the most abundant species on the planet;"
"though Huxley presented the Ichthyopsida as an informal unit and never ventured to forward a Linnaean rank for the group. The term ichthyopsida means ""fish-face"" or ""fish-like"" as opposed to the sauropsida or ""lizard-face"" animals (reptiles and birds) and the mammals. The group representing an evolutionary grade rather than a clade, the term anamniote is now used as an informal way of denoting the physical property of the group, rather than as a systematic unit. Anamniotes The anamniotes are an informal group comprising the fishes and the amphibians, the so-called ""lower vertebrates"", which lay their eggs in water. They are"
"category of ""reptiles"" that consisted of a miscellany of egg-laying creatures, including ""snakes, various fantastic monsters, […], assorted amphibians, and worms"", as recorded by Vincent of Beauvais in his ""Mirror of Nature"". The seventeenth century saw changes in this loose description. The name Sauria was coined by James Macartney (1802); it was the Latinisation of the French name ""Sauriens"", coined by Alexandre Brongniart (1800) for an order of reptiles in the classification proposed by the author, containing lizards and crocodilians, later discovered not to be each other's closest relatives. Later authors used the term ""Sauria"" in a more restricted sense,"
"scale up from counts at specific locations applied to the whole world. A study in 1992 estimated that there were 500,000 species of animals and plants in Costa Rica alone, of which 365,000 were arthropods. They are important members of marine, freshwater, land and air ecosystems, and are one of only two major animal groups that have adapted to life in dry environments; the other is amniotes, whose living members are reptiles, birds and mammals. One arthropod sub-group, insects, is the most species-rich member of all ecological guilds in land and freshwater environments. The lightest insects weigh less than 25"
"Fauna Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ""flora"". Flora, fauna and other forms of life such as fungi are collectively referred to as ""biota"". Zoologists and paleontologists use ""fauna"" to refer to a typical collection of animals found in a specific time or place, e.g. the ""Sonoran Desert fauna"" or the ""Burgess Shale fauna"". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. ""Fauna"" comes"
"Paul M. Barrett. Thyreophora Thyreophora (""shield bearers"", often known simply as ""armored dinosaurs"" - Greek: ""θυρεος"", thyreos, a large oblong shield, like a door and ""φορεω"", I carry) is a group of armored ornithischian dinosaurs that lived from the early Jurassic Period until the end of the Cretaceous. Thyreophorans are characterized by the presence of body armor lined up in longitudinal rows along the body. Primitive forms had simple, low, keeled scutes or osteoderms, whereas more derived forms developed more elaborate structures including spikes and plates. Most thyreophorans were herbivorous and had relatively small brains for their body size. Thyreophora"
"Mammal Mammals ( from Latin ""mamma"" ""breast"") are vertebrate animals constituting the class Mammalia, and characterized by the presence of mammary glands, which in females produce milk for feeding (nursing) their young; a neocortex (a region of the brain); hair; and three middle ear bones. These characteristics distinguish them from reptiles and birds, from which they diverged in the late Triassic. There are around 5,450 species of mammals. The largest orders are the rodents, bats and Soricomorpha (shrews and allies). The next three are the Primates (apes, monkeys, and allies), the Cetartiodactyla (whales and even-toed ungulates), and the Carnivora (cats,"