- 行业: Internet
- Number of terms: 16478
- Number of blossaries: 4
- Company Profile:
Wikipedia is a collaboratively edited, multilingual, free Internet encyclopedia supported by the non-profit Wikimedia Foundation.
Batoidea is a superorder of cartilaginous fish commonly known as rays and skates, approximately 560 described species in thirteen families. They are in the fish subclass Elasmobranchii, along with sharks.
They are closely related to sharks, from which they can be distinguished by their flattened bodies, enlarged pectoral fins that are fused to the head, and gill slits that are placed on their ventral surfaces.
Industry:Animals
Beaked whales are the members of the family Ziphiidae which consists of 21 species. These toothed whales are notable for their elongated beaks. Beaked whales are some of the world’s most extreme divers. They can dive for long periods—20 to 30 minutes is common, and 85 minute dives have been recorded—and to great depths: 1,899 meters (6,230 ft) and possibly more.
Beaked whales are one of the least known groups of mammals because of their deep-sea habitat, mysterious habits, and apparent low abundance. Only three to four of the 21 species are reasonably well-known. Baird’s and Cuvier's beaked whales were subject to commercial exploitation, off the coast of Japan, while the Northern bottlenose whale was extensively hunted in the northern part of the North Atlantic late in the 19th and early in the 20th centuries.
Industry:Animals
Bears are mammals of the family Ursidae. Bears are classified as caniforms, or doglike carnivorans, with the pinnipeds being their closest living relatives. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout the Northern Hemisphere and partially in the Southern Hemisphere. Bears are found on the continents of North America, Central America, South America, Europe, and Asia.
Common characteristics of modern bears include large bodies with stocky legs, long snouts, shaggy hair, plantigrade paws with five nonretractile claws, and short tails. While the polar bear is mostly carnivorous and the giant panda feeds almost entirely on bamboo, the remaining six species are omnivorous, with varied diets.
With the exceptions of courting individuals and mothers with their young, bears are typically solitary animals. They are generally diurnal, but may be active during the night (nocturnal) or twilight (crepuscular), particularly around humans. Bears are aided by an excellent sense of smell, and despite their heavy build and awkward gait, they can run quickly and are adept climbers and swimmers. In autumn, some bear species forage large amounts of fermented fruits, which affects their behaviour. Bears use shelters, such as caves and burrows, as their dens; most species occupy their dens during the winter for a long period (up to 100 days) of sleep similar to hibernation.
Bears have been hunted since prehistoric times for their meat and fur. With their tremendous physical presence and charisma, they play a prominent role in the arts, mythology, and other cultural aspects of various human societies. In modern times, the bears' existence has been pressured through the encroachment on their habitats and the illegal trade of bears and bear parts, including the Asian bile bear market. The IUCN lists six bear species as vulnerable or endangered, and even least concern species, such as the brown bear, are at risk of extirpation in certain countries. The poaching and international trade of these most threatened populations are prohibited, but still ongoing.
Industry:Animals
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila. There are nearly 20,000 known species of bees in seven to nine recognized families, though many are undescribed and the actual number is probably higher. They are found on every continent except Antarctica, in every habitat on the planet that contains insect-pollinated flowering plants.
Bees are adapted for feeding on nectar and pollen, the former primarily as an energy source and the latter primarily for protein and other nutrients. Most pollen is used as food for larvae.
Bees have a long proboscis (a complex "tongue") that enables them to obtain the nectar from flowers. They have antennae almost universally made up of 13 segments in males and 12 in females, as is typical for the superfamily. Bees all have two pairs of wings, the hind pair being the smaller of the two; in a very few species, one sex or caste has relatively short wings that make flight difficult or impossible, but none are wingless.
The smallest bee is Trigona minima, a stingless bee whose workers are about 2.1 mm (5/64") long. The largest bee in the world is Megachile pluto, a leafcutter bee whose females can attain a length of 39 mm (1.5"). Members of the family Halictidae, or sweat bees, are the most common type of bee in the Northern Hemisphere, though they are small and often mistaken for wasps or flies.
The best-known bee species is the European honey bee, which, as its name suggests, produces honey, as do a few other types of bee. Human management of this species is known as beekeeping or apiculture.
Bees are the favorite meal of Merops apiaster, the bee-eater bird. Other common predators are kingbirds, mockingbirds, beewolves, and dragonflies.
Industry:Animals
Birds (class Aves or clade Avialae) are feathered, winged, bipedal, endothermic (warm-blooded) egg-laying, vertebrate animals. Aves, with approximately ten thousand living species, is the most speciose class of tetrapod vertebrate. Extant birds belong to the subclass Neornithes, live worldwide, and range in size from the 5 cm (2 in) Bee Hummingbird to the 2.75 m (9 ft) Ostrich. The fossil record indicates that birds emerged within theropod dinosaurs during the Jurassic period, around 150 million years ago. Birds are the only members of the clade that originated with the earliest dinosaurs that survived the Cretaceous–Paleogene extinction event 66 million years ago.
Modern birds are characterised by feathers, a beak with no teeth, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. Extant birds have wings; the most recent species without wings was the moa, which is generally considered to have become extinct in the 16th century. Wings are evolved forelimbs, and most bird species can fly. Flightless birds include ratites, penguins, and diverse endemic island species. Some species of birds, particularly penguins and members of the Anatidae family, are adapted to swim. Birds also have digestive and respiratory systems that are uniquely adapted for flight. Some birds, especially corvids and parrots, are among the most intelligent animal species; several bird species make and use tools, and many social species culturally transmit knowledge across generations.
Many species annually migrate great distances, and many more perform shorter irregular movements. Birds are social, communicating with visual signals, calls, and songs, and participating in such social behaviours as cooperative breeding and hunting, flocking, and mobbing of predators. The vast majority of bird species are socially monogamous, usually for one breeding season at a time, sometimes for years, but rarely for life. Other species have polygynous ("many females") or, rarely, polyandrous ("many males") breeding systems. Eggs are usually laid in a nest and incubated by the parents. Most birds have an extended period of parental care after hatching.
Many species are economically important, mostly as game or poultry. Some species, particularly songbirds and parrots, are popular as pets. Another use of birds is harvesting guano (droppings) for use as a fertiliser. Birds prominently figure throughout human culture. About 120–130 species have become extinct due to human activity since the 17th century, and hundreds more before then. Human acitivity threatens about 1,200 bird species with extinction, though efforts are underway to protect them.
Industry:Animals
Bison are large, even-toed ungulates in the genus Bison within the subfamily Bovinae.
There are two extant and four extinct species recognized. Of the four extinct species, three were North American: Bison antiquus, B. latifrons, and B. occidentalis. The fourth, Bison priscus, ranged across steppe environments from Western Europe, through Central Asia, and onto North America.
There are two surviving species: the American bison, Bison bison, found only in North America, is the most numerous. (It is only distantly related to the buffalo.) The North American species is composed of two subspecies, the plains bison, Bison bison bison, and the wood bison, Bison bison athabascae, which is the namesake of Wood Buffalo National Park in Canada. The European bison Bison bonasus, or wisent is found in Europe and the Caucasus, re-introduced after being extinct in the wild.
While all bison species are usually grouped into their own genus, they are sometimes included in the closely related genus Bos, together with cattle, gaur, kouprey and yaks, with which bison have a limited ability to interbreed.
Industry:Animals
Cardinals, in the family Cardinalidae, are passerine birds found in North and South America. They are also known as cardinal-grosbeaks and cardinal-buntings. The South American cardinals in the genus Paroaria are placed in another family, the Thraupidae (previously placed in Emberizidae).
These are robust, seed-eating birds with strong bills. The family ranges in size from the 12-cm (4.7 inches), 11.5-gram (.40 oz) Orange-breasted Bunting to the 25-cm (9.8 inches), 85-gram (2.99 oz) Black-headed Saltator(verification needed). They are typically associated with open woodland. The sexes usually have distinctive appearances. The Northern Cardinal type species was named by colonists for the male's red crest, reminiscent of a Catholic cardinal's mitre.
The "buntings" in this family are sometimes generically known as "tropical buntings" (though not all live in the tropics) or "North American buntings" (though there are other buntings in North America) to distinguish them from the true buntings, whose family does contain North American birds, but they are referred to as American sparrows (unrelated to Old World sparrows), juncos, and towhees rather than buntings. Likewise the grosbeaks in this family are sometimes called "cardinal-grosbeaks" to distinguish them from other grosbeaks. The name "cardinal-grosbeak" can also apply to this family as a whole.
Most species are rated by the IUCN as least concern, though some are near threatened.1) "Masked clade:2) "Blue" clade:3) Ant tanager clade:4) "Chat" clade:5) "Pheucticus" clade:Incertae sedis - these birds traditionally placed in the cardinal family are biochemically related to various tanager (Thraupidae) groups:
Industry:Animals
Carp are various species of oily freshwater fish of the family Cyprinidae, a very large group of fish native to Europe and Asia.
The cypriniformes (family Cyprinidae) are traditionally grouped with the Characiformes, Siluriformes and Gymnotiformes to create the superorder Ostariophysi, since these groups have certain common features, such as being found predominantly in fresh water and that they possess Weberian ossicles (an anatomical structure originally made up of small pieces of bone formed from four or five of the first vertebrae); the most anterior bony pair is in contact with the extension of the labyrinth and the posterior with the swimbladder. The function is poorly understood, but this structure is presumed to take part in the transmission of vibrations from the swimbladder to the labyrinth and in the perception of sound, which would explain why the Ostariophysi have such a great capacity for hearing.
Most cypriniformes have scales and teeth on the inferior pharyngeal bones which may be modified in relation to the diet. Tribolodon is the only cyprinid genus which tolerates salt water, although there are several species which move into brackish water, but return to fresh water to spawn. All of the other cypriniformes live in continental waters and have a wide geographical range. Some consider all cyprinid fishes carp, and the family Cyprinidae itself is often known as the carp family. In colloquial use, carp usually refers only to several larger cyprinid species such as Cyprinus carpio (common carp), Carassius carassius (Crucian carp), Ctenopharyngodon idella (grass carp), Hypophthalmichthys molitrix (silver carp), and Hypophthalmichthys nobilis (bighead carp). Carp have long been an important food fish to humans, as well as popular ornamental fishes such as the various goldfish breeds and the domesticated common carp variety known as koi. As a result, carp have been introduced to various locations, though with mixed results. Several species of carp are listed as invasive species by the U.
S. Department of Agriculture, and worldwide large sums of money are spent on carp control.
Industry:Animals
Celestus is a genus of Anguid lizards. It has 25 living member species.
Genus Celestus
Industry:Animals
Centipedes (from Latin prefix centi-, "hundred", and pes, pedere, "foot") are arthropods belonging to the class Chilopoda of the subphylum Myriapoda. They are elongated metameric creatures with one pair of legs per body segment. Despite the name, centipedes can have a varying number of legs from under 20 to over 300. Centipedes have an odd number of pairs of legs, e.g. 15 or 17 pairs of legs (30 or 34 legs). A key trait uniting this group is a pair of venom claws or forcipules formed from a modified first appendage. Centipedes are a predominantly carnivorous taxon.:168Centipedes normally have a drab coloration combining shades of brown and red. Cavernicolous (cave-dwelling) and subterranean species may lack pigmentation and many tropical scolopendromorphs have bright aposematic colours. Size can range from a few millimetres in the smaller lithobiomorphs and geophilomorphs to about 30 cm (12 in) in the largest scolopendromorphs. Centipedes can be found in a wide variety of environments.
Worldwide, there are estimated to be 8,000 species of centipede, of which 3,000 have been described. Centipedes have a wide geographical range, reaching beyond the Arctic Circle. Centipedes are found in an array of terrestrial habitats from tropical rainforests to deserts. Within these habitats, centipedes require a moist micro-habitat because they lack the waxy cuticle of insects and arachnids, and so lose water rapidly through the skin. Accordingly, they are found in soil and leaf litter, under stones and dead wood, and inside logs. Centipedes are among the largest terrestrial invertebrate predators and often contribute significantly to the invertebrate predatory biomass in terrestrial ecosystems.
Industry:Animals
