Sumonsenji

Anacondas are large, nonvenomous boas of the genus Eunectes. They are found in tropical South America.

The most familiar species is the green anaconda, "Eunectes murinus", notable for being one of the world's largest snakes. Green anacondas can grow to be 5.21 m (17 ft) in length and weighing 97.5 kg (215 lb).[1] They are found east of the Andes in Colombia, Venezuela, the Guianas, Ecuador, Peru, Bolivia, Brazil, and on the island of Trinidad.

Other anacondas are the yellow anaconda, Eunectes notaeus, a smaller species found in eastern Bolivia, southern Brazil, Paraguay and northeastern Argentina; and the dark-spotted anaconda, "Eunectes deschauenseei", a rare species found in northeastern Brazil, coastal French Guiana and Guyana.

All three species are aquatic snakes that prey on other aquatic animals, including fish, river fowl, caiman, and capybaras. Some accounts exist of anacondas preying on domestic animals such as goats and ponies that venture too close to the water.

While encounters between people and anacondas may be dangerous, they do not regularly hunt humans. Nevertheless, threat from anacondas is a familiar trope in comics, movies and adventure stories set in the Amazon jungle. Anacondas have also figured prominently in South American folklore, where they are sometimes depicted as shapeshifting mythical creatures called encantados. Local communities and some European explorers have given accounts of giant anacondas, legendary snakes of much greater proportion than any confirmed specimen.

Applied loosely, the term "anaconda" may also refer to any large snake that "crushes" its prey by constricting.The Merriam-Webster online dictionary states[3] the word is probably a modification of the Sinhalese word henakandayā,[4][5][6] which is used to refer to a small slender green whip snake found in Sri Lanka. However, certain other literature[7][8] state henakandayā refers to a now extinct constrictor once found there. Richard Boyle (the Sri Lankan English consultant to the Oxford English Dictionary) writes in his book 'Sinbad In Serendib':[9]

The first reference to the anaconda in English is by R. Edwin (probably a pseudonym) in a letter to the Scots magazine concerning an encounter with a tiger-devouring serpent in then Dutch-held Ceylon. This was published in the 1768 issue under the discursive heading, "Description of the ANACONDA, a monstrous species of serpent. In a letter from an English gentleman, many years resident in the island of Ceylon, in the East Indies."[10] However, this account of an incident on the outskirts of Colombo is a figment of the imagination, full of the popular misconceptions regarding constrictors in an age of limited scientific knowledge of snakes.
—Richard Boyle

The Oxford English Dictionary gives a first source as John Ray's "List of Indian Serpents" from the Leyden Museum, as "anacandaia of the Ceylonese, i.e. he that crushes the limbs of buffaloes and yoke beasts," but that "anacandaia" is "not now a native name in Sri Lanka, and not satisfactorily explained either in Cingalese [Sinhalese] or Tamil"—though Henry Yule lists "āṇaik'k'onḍa" to means "having killed an elephant" in Tamil.

The anaconda is a large, non-venomous snake native to tropical South America and Northern Africa. They mostly live in swampy or watery areas. The green anaconda is the biggest snake in the world, with the largest measuring up to 37.5 feet in length. The anaconda is related to the boa constrictor snake. They kill their prey by constriction or squeezing. They wrap themselves around their prey and squeeze to prevent the prey from breathing. They then swallow the animal whole. Play the following videos to learn more about the anaconda snake.

Dinosaurs are a diverse group of reptiles. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period (about 230 million years ago) until the end of the Cretaceous period (about 65 million years ago), when the Cretaceous–Tertiary extinction event caused the extinction of most dinosaur species, except for some birds. The fossil record indicates that birds evolved from theropod dinosaurs during the Jurassic period, and most paleontologists regard them as the only group of dinosaurs to have survived until the present day.[1]

Dinosaurs are a diverse and varied group of animals; birds, at over 9,000 species, are the most diverse group of vertebrate besides perciform fish.[2] Paleontologists have identified over 500 distinct genera[3] and more than 1,000 different species of non-avian dinosaurs.[4] Dinosaurs are represented on every continent by both extant species and fossil remains.[5] Some dinosaurs are or were herbivorous, others carnivorous. Some have been bipedal, others quadrupedal, and others have been able to shift between these body postures. Many non-avian species developed elaborate skeletal modifications such as bony armor, horns or crests. Avian dinosaurs have been the planet's dominant flying vertebrate since the extinction of the pterosaurs. Although generally known for the large size of some species, most dinosaurs were human-sized or even smaller. Most groups of dinosaurs are known to have built nests and laid eggs.

The term "dinosaur" was coined in 1842 by the English paleontologist Richard Owen, and derives from Greek δεινός (deinos) "terrible, powerful, wondrous" + σαῦρος (sauros) "lizard". Through the first half of the twentieth century, most of the scientific community mistakenly believed dinosaurs to have been sluggish, unintelligent cold-blooded animals. Most research conducted since the 1970s, however, has indicated that dinosaurs were active animals with elevated metabolisms and numerous adaptations for social interaction.

Since the first dinosaur fossils were recognized in the early nineteenth century, mounted dinosaur skeletons have been major attractions at museums around the world, and dinosaurs have become a part of world culture. They have been featured in best-selling books and films such as Jurassic Park, and new discoveries are regularly covered by the media. The outdated image of dinosaurs as maladapted extinct monsters has led to the word "dinosaur" entering the vernacular to describe anything that is impractically large, slow-moving, obsolete, or bound for extinction.[6]The taxon Dinosauria was formally named in 1842 by Sir Richard Owen, who used it to refer to the "distinct tribe or sub-order of Saurian Reptiles" that were then being recognized in England and around the world.[7] The term is derived from the Greek words δεινός (deinos meaning "terrible", "powerful", or "wondrous") and σαῦρος (sauros meaning "lizard" or "reptile").[8] Though the taxonomic name has often been interpreted as a reference to dinosaurs' teeth, claws, and other fearsome characteristics, Owen intended it merely to evoke their size and majesty.[9] In colloquial English "dinosaur" is sometimes used to describe an obsolete or unsuccessful thing or person,[10] despite the dinosaurs' 160 million year reign and the global abundance and diversity of their avian descendants: modern-day birds.

The thylacine (pronounced /ˈθaɪləsaɪn/,[3] or in Australia /ˈθaɪləsiːn/,[4] also /ˈθaɪləsɨn/[5]) (binomial name: Thylacinus cynocephalus; Greek for "dog-headed pouched one") was the largest known carnivorous marsupial of modern times. It is commonly known as the Tasmanian tiger (because of its striped back), the Tasmanian wolf, and colloquially the Tassie tiger or simply the tiger.[6] Native to continental Australia, Tasmania and New Guinea, it is thought to have become extinct in the 20th century. It was the last extant member of its genus, Thylacinus, although several related species have been found in the fossil record dating back to the early Miocene.

The thylacine had become extremely rare or extinct on the Australian mainland before European settlement of the continent, but it survived on the island state of Tasmania along with several other endemic species, including the Tasmanian devil. Intensive hunting encouraged by bounties is generally blamed for its extinction, but other contributory factors may have been disease, the introduction of dogs, and human encroachment into its habitat. Despite its official classification as extinct, sightings are still reported, though none proven.

Like the tigers and wolves of the Northern Hemisphere, from which it obtained two of its common names, the thylacine was an apex predator. As a marsupial, it was not closely related to these placental mammals, but because of convergent evolution it displayed the same general form and adaptations. Its closest living relative is thought to be either the Tasmanian devil or numbat.

The thylacine was one of only two marsupials to have a pouch in both sexes (the other being the water opossum). The male thylacine had a pouch that acted as a protective sheath, protecting the male's external reproductive organs while running through thick brush.

The hippopotamus (Hippopotamus amphibius), or hippo, from the ancient Greek for "river horse" (Ιπποπόταμος), is a large, mostly herbivorous mammal in sub-Saharan Africa, and one of only two extant species in the family Hippopotamidae (the other is the Pygmy Hippopotamus.) The hippopotamus is the third largest land animal (after the elephant and the white rhinoceros) and the heaviest extant artiodactyl, despite being considerably shorter than the giraffe.

The hippopotamus is semi-aquatic, inhabiting rivers and lakes where territorial bulls preside over a stretch of river and groups of 5 to 30 females and young. During the day they remain cool by staying in the water or mud; reproduction and childbirth both occur in water. They emerge at dusk to graze on grass. While hippopotamuses rest near each other in the water, grazing is a solitary activity and hippos are not territorial on land.

Despite their physical resemblance to pigs and other terrestrial even-toed ungulates, their closest living relatives are cetaceans (whales, porpoises, etc.) from which they diverged about 55 million years ago.[3] The common ancestor of whales and hippos split from other even-toed ungulates around 60 million years ago.[4] The earliest known hippopotamus fossils, belonging to the genus Kenyapotamus in Africa, date to around 16 million years ago.

The hippopotamus is recognizable by its barrel-shaped torso, enormous mouth and teeth, nearly hairless body, stubby legs and tremendous size. It is the third-largest land mammal by weight (between 1½ and 3 tonnes), behind the white rhinoceros (1½ to 3½ tonnes) and both species of elephant (3 to 9 tonnes). Despite its stocky shape and short legs, it can easily outrun a human. Hippos have been clocked at 30 km/h (19 mph) over short distances. The hippopotamus is one of the most aggressive creatures in the world and is often regarded as the most ferocious animal in Africa. There are an estimated 125,000 to 150,000 hippos throughout Sub-Saharan Africa; Zambia (40,000) and Tanzania (20,000–30,000) possess the largest populations.[1] They are still threatened by habitat loss and poaching for their meat and ivory canine teeth.

Rhinoceros (pronounced /raɪˈnɒsərəs/), often colloquially abbreviated rhino, is a group of five extant species of odd-toed ungulates in the family rhinocerotidae. Two of these species are native to Africa and three to southern Asia. Three of the five species—the Javan, Sumatran and Black Rhinoceros—are critically endangered. The greater, one-horned Indian Rhinoceros is endangered, with fewer than 2,700 individuals remaining in the wild. The White is registered as "vulnerable", with approximately 17,500 remaining in the wild, as reported by the International Rhino Foundation.[1][2]

The rhinoceros family is characterized by its large size (one of the largest remaining megafauna alive today), with all of the species able to reach one ton or more in weight; herbivorous diet; and a thick protective skin, 1.5–5 cm thick, formed from layers of collagen positioned in a lattice structure; relatively small brains for mammals this size (400–600 g); and a large horn. They generally eat leafy material, although their ability to ferment food in their hindgut allows them to subsist on more fibrous plant matter, if necessary. Unlike other perissodactyls, the African species of rhinoceros lack teeth at the front of their mouths, relying instead on their powerful premolar and molar teeth to grind up plant food.[3]

The rhino is killed by humans for its horn. The horns of a rhinoceros are made of keratin, the same type of protein that makes up hair and fingernails.[4] Both African species and the Sumatran Rhinoceros have two horns, while the Indian and Javan Rhinoceros have a single horn. Rhinoceroses have acute hearing and sense of smell, but poor eyesight. Most live to be about 60 years old or more.The word rhinoceros is derived through Latin from the Greek ῥῑνόκερως, which is composed of ῥῑνο-, ῥίς (rhino-, rhis), meaning nose, and κέρας (keras), meaning horn. The standard plural in English is rhinoceroses. The collective noun for a group of rhinoceros is crash or herd.[5]

Size comparison of extant rhinoceros species

The five living species fall into three categories. The two African species, the White Rhinoceros and the Black Rhinoceros, diverged during the early Pliocene (about 5 million years ago) but the Dicerotini group to which they belong originated in the middle Miocene, about 14.2 million years ago. The main difference between black and white rhinos is the shape of their mouths. White rhinos have broad flat lips for grazing and black rhinos have long pointed lips for eating foliage. A popular—if unverified—theory claims that the name White Rhinoceros was actually a mistake, or rather a corruption of the word wyd ("wide" in Afrikaans), referring to their square lips.[6]

White Rhinoceros are divided into Northern and Southern subspecies. There are two living Rhinocerotini species, the endangered Indian Rhinoceros and the critically endangered Javan Rhinoceros, which diverged from one another about 10 million years ago. The critically endangered Sumatran Rhinoceros is the only surviving representative of the most primitive group, the Dicerorhinini, which emerged in the Miocene (about 20 million years ago).[7] The extinct Woolly Rhinoceros of northern Europe and Asia was also a member of this tribe.

A subspecific hybrid white rhino (Ceratotherium s. simum × C. s. cottoni) was bred at the Dvůr Králové Zoo (Zoological Garden Dvur Kralove nad Labem) in the Czech Republic in 1977. Interspecific hybridisation of Black and White Rhinoceros has also been confirmed.[8]

All rhinoceros species have 82 chromosomes (diploid number, 2N, per cell), except the Black Rhinoceros, which has 84. This is the highest known chromosome number of all mammals.
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White Rhinoceros

These White Rhinoceros are actually gray. The White in this species' name is from the Dutch word wijd which means wide. It refers to the White Rhinoceros's wide lip compared to the Black Rhinoceros's pointed lip. The original meaning was subsequently lost in translation.
Main article: White Rhinoceros

The White or Square-lipped Rhinoceros (Ceratotherium simum) is, after the elephant, the most massive remaining land animal in the world, along with the Indian Rhinoceros and the hippopotamus, which are of comparable size. There are two subspecies of White Rhinos; as of 2005, South Africa has the most of the first subspecies, the Southern White Rhinoceros (Ceratotherium simum simum). The population of Southern White Rhinos is about 14,500, making them the most abundant subspecies of rhino in the world. However, the population of the second subspecies, the critically endangered Northern White Rhinoceros (Ceratotherium simum cottoni), is down to as few as four individuals in the wild, and as of June 2008 this sub-species are thought to have become extinct in the wild.[9]. Six are known to be held in captivity, two of which reside in a zoo in San Diego. There are currently four that were in held in captivity since 1982 in a zoo in the Czech Republic which were transferred to a wildlife refuge in Kenya in December 2009, in an effort have the animals reproduce and save the subspecies[10].

The White Rhino has an immense body and large head, a short neck and broad chest. This rhino can exceed 3,500 kg (7,700 lb), have a head-and-body length of 3.5–4.6 m (11–15 ft) and a shoulder height of 1.8–2 m (5.9–6.6 ft) The record-sized White Rhinoceros was about 4,600 kg (10,000 lb).[11] On its snout it has two horns. The front horn is larger than the other horn and averages 90 cm (35 in) in length and can reach 150 cm (59 in). The White Rhinoceros also has a prominent muscular hump that supports its relatively large head. The colour of this animal can range from yellowish brown to slate grey. Most of its body hair is found on the ear fringes and tail bristles with the rest distributed rather sparsely over the rest of the body. White Rhinos have the distinctive flat broad mouth which is used for grazing. White rhinos aren't actually white, they are named after the Dutch word for wide.

The lion (Panthera leo) is one of the four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg (550 lb) in weight,[4] it is the second-largest living cat after the tiger. Wild lions currently exist in Sub-Saharan Africa and in Asia with a critically endangered remnant population in Gir Forest National Park in India, having disappeared from North Africa and Southwest Asia in historic times. Until the late Pleistocene, about 10,000 years ago, the lion was the most widespread large land mammal after humans. They were found in most of Africa, much of Eurasia from western Europe to India, and in the Americas from the Yukon to Peru.

Lions live for ten to fourteen years in the wild, while in captivity they can live longer than twenty years. In the wild, males seldom live longer than ten years, as injuries sustained from continual fighting with rival males greatly reduce their longevity.[5] They typically inhabit savanna and grassland, although they may take to bush and forest. Lions are unusually social compared to other cats. A pride of lions consists of related females and offspring and a small number of adult males. Groups of female lions typically hunt together, preying mostly on large ungulates. Lions are apex and keystone predators, although they scavenge as opportunity allows. While lions do not typically hunt humans selectively, some have been known to seek human prey.

The lion is a vulnerable species, having seen a possibly irreversible population decline of thirty to fifty percent over the past two decades in its African range.[6] Lion populations are untenable outside of designated reserves and national parks. Although the cause of the decline is not fully understood, habitat loss and conflicts with humans are currently the greatest causes of concern. Lions have been kept in menageries since Roman times and have been a key species sought for exhibition in zoos the world over since the late eighteenth century. Zoos are cooperating worldwide in breeding programs for the endangered Asiatic subspecies.

Visually, the male lion is highly distinctive and is easily recognized by its mane. The lion, particularly the face of the male, is one of the most widely recognized animal symbols in human culture. Depictions have existed from the Upper Paleolithic period, with carvings and paintings from the Lascaux and Chauvet Caves, through virtually all ancient and medieval cultures where they historically occurred. It has been extensively depicted in literature, in sculptures, in paintings, on national flags, and in contemporary films and literature.

Elephants are large land mammals in two genera of the family Elephantidae: Elephas and Loxodonta. Three species of elephant are living today: the African Bush Elephant, the African Forest Elephant and the Asian Elephant (also known as the Indian Elephant). All other species and genera of Elephantidae are extinct, some since the last ice age: dwarf forms of mammoths may have survived as late as 2,000 BC.[1] Elephants and other Elephantidae were once classified with other thick-skinned animals in a now invalid order, Pachydermata.

Elephants are the largest land animals now living.[2] The elephant's gestation period is 22 months, the longest of any land animal. At birth it is common for an elephant calf to weigh 120 kilograms (260 lb). They typically live for 50 to 70 years, but the oldest recorded elephant lived for 82 years.[3] The largest elephant ever recorded was shot in Angola in 1956. This male weighed about 24,000 lb (11,000 kg),[4] with a shoulder height of 3.96 metres (13.0 ft), a metre (yard) taller than the average male African elephant.[5] The smallest elephants, about the size of a calf or a large pig, were a prehistoric species that lived on the island of Crete during the Pleistocene epoch.[6]

Elephants are a symbol of wisdom in Asian cultures and are famed for their memory and intelligence, where they are thought to be on par with cetaceans[7] and hominids.[8] Aristotle once said the elephant was "the beast which passeth all others in wit and mind".[9] The word "elephant" has its origins in the Greek ἐλέφας, meaning "ivory" or "elephant".[10]

According to observations so far, healthy adult elephants have no natural predators,[11] although lions may take calves or weak individuals.[12][13] They are, however, threatened by human intrusion and poaching.

Zebras are African equids best known for their distinctive white and black stripes. Their stripes come in different patterns unique to each individual. They are generally social animals and can be seen in small harems to large herds. In addition to their stripes, zebras have erect, mohawk-like manes. Unlike their closest relatives, horses and asses, zebras have never been truly domesticated.

There are three species of zebra: the Plains Zebra, Grévy's Zebra and the Mountain Zebra. The Plains zebra and the Mountain zebra belong to the subgenus Hippotigris, but Grevy's zebra is the sole species of subgenus Dolichohippus. The latter resembles an ass while the former two are more horse-like. Nevertheless, DNA and molecular data show that zebras do indeed have monophyletic origins. All three belong to the genus Equus along with other living equids. In certain regions of Kenya, Plains zebras and Grevy's zebras coexist.

The unique stripes and behaviors of zebras make these among the animals most familiar to people. They can be found in a variety of habitats, such as grasslands, savannas, woodlands, thorny scrublands, mountains and coastal hills. However, various anthropogenic factors have had a severe impact on zebra populations, in particular hunting for skins and habitat destruction. Grevy's zebra and the Mountain zebra are endangered. While Plains zebras are much more plentiful, one subspecies, the quagga, went extinct in the late nineteenth century.

The genus name Okapia derives from the Lese Karo name o'api[citation needed], while the species' epithet (johnstoni) is in recognition of the explorer Sir Harry Johnston, who organized the expedition that first acquired an okapi specimen for science from the Ituri Forest in the Democratic Republic of the Congo.

The name "Okapi" is a portmanteau of two Lese words, oka a verb meaning to cut and kpi which is a noun referring to the design made on Efé arrows by wrapping the arrow with bark so as to leave stripes when scorched by fire. The stripes on the legs of the Okapi resemble these stripes on the arrow shafts. Lese legend says the okapi decorates itself with these stripes, adding to the okapi's great camouflage.Okapis have reddish dark backs, with striking horizontal white stripes on the front and back legs, making them resemble zebras from a distance. These markings are thought to help young follow their mothers through the dense rain forest;[citation needed] they also serve as camouflage in the wild.[citation needed]

The body shape is similar to that of the giraffe, except that okapis have much shorter necks. Both species have very long (approximately 30 centimetres (12 in), flexible, blue tongues that they use to strip leaves and buds from trees.

An okapi cleaning its muzzle with its tongue.

The tongue of the okapi is long enough for the animal to wash its eyelids and clean its ears (inside and out). 35 to 46 centimetres (14 to 18 in) in length, the sticky tongue is pointed and bluish grey in colour like the giraffe's. Male okapis have short, skin-covered horns called ossicones. They have large ears, which help them detect their predator, the leopard.

Okapis are 1.9 to 2.5 metres (6.2 to 8.2 ft) long and stand 1.5 to 2.0 metres (4.9 to 6.6 ft) high at the shoulder. They have a 30 to 42 centimetres (12 to 17 in) long tail. Their weight ranges from 200 to 300 kilograms (440 to 660 lb). Okapis are primarily diurnal, although recent photo captures have challenged this long held assumption. One photograph taken at 02:33 am shows an okapi feeding in the Watalinga forest in the north of the Virunga National Park in eastern DRC, thus providing evidence that they don't only feed during the daytime.[citation needed] Okapis are essentially solitary, coming together only to breed, with the exception of mothers and offspring. Breeding behaviours include sniffing, circling and licking each other.[3]

Okapis forage along fixed, well-trodden paths through the forest. They have overlapping home ranges of several square kilometres and typically occur at densities of about 0.6 animals per square kilometre (about 1.5 animals per square mile). They are not social animals and prefer to live in large, secluded areas. This has led to problems with the okapi population due to the shrinking size of the land they live on. This lack of territory is caused by development and other social reasons. However, okapis tolerate each other in the wild and may even feed in small groups for short periods of time.[citation needed]

Okapis have several methods of communicating their territory, including scent glands on each foot that produce a tar-like substance, as well as urine marking. Males are protective of their territory, but allow females to pass through their domain to forage.

Okapi young are not imprinted to their mothers.[citation needed] Several lactating females will raise their calves together.