Bear And Hippopotamus

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Bears are mammals of the family Ursidae. Bears are classified as caniforms, or doglike carnivorans, with the pinnipeds being their closest living relatives. Although there are only eight living species of bear, they are widespread, appearing in a wide variety of habitats throughout the Northern Hemisphere and partially in the Southern HemisphereSony VAIO PCG-31114V battery. Bears are found in the continents of North America, South America, Europe, and Asia.

Common characteristics of modern bears include a large body with stocky legs, a long snout, shaggy hair, plantigrade paws with five nonretractile claws, and a short tail. While the polar bear is mostly carnivorous and the giant panda feeds almost entirely on bamboo, the remaining six species are omnivorous, with largely varied diets including both plants and animalsSony VAIO PCG-31113V battery.

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 gaitSony VAIO PCG-31112V battery, 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.[1] Bears use shelters such as caves and burrows as their dens, which are occupied by most species during the winter for a long period of sleep similar to hibernationSony VAIO PCG-31111V battery.

Bears have been hunted since prehistoric times for their meat and fur. To this day, they play a prominent role in the arts, mythology, and other cultural aspects of various human societies. In modern times, the bear's existence has been pressured through the encroachment on its 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 endangeredSony VAIO PCG-31114M battery, 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.

Etymology

The English word "bear" comes from Old English bera and belongs to a family of names for the bear in Germanic languages, in origin from an adjective meaning "brown".Sony VAIO PCG-31113M battery In Scandinavia the word for bear is björn (or bjørn), and is a relatively common given name for males. The use of this name is ancient and has been found mentioned in several runestone inscriptions.[3] In Germanic culture, the bear was a symbol of the warrior, as evident from the Old English term beorn which can take the meaning of both "bear" and "warrior"Sony VAIO PCG-31112M battery.

The reconstructed Proto-Indo-European name of the bear is *h₂ŕ̥tḱos, whence Sanskrit r̥kṣa, Avestan arša, Greek ἄρκτος (arktos), Latin ursus, Welsh arth (whence perhaps "Arthur"), Albanian ari, Armenian arj. Also compared is Hittite ḫartagga-, the name of a monster or predator.[2] In the binomial name of the brown bear, Ursus arctos, Linné simply combined the Latin and Greek namesSony VAIO PCG-31111M battery.

The Proto-Indo-European word for bear, *h₂ŕ̥tḱos seems to have been subject to taboo deformation or replacement in some languages (as was the word for wolf, wlkwos), resulting in the use of numerous unrelated words with meanings like "brown one" (English bruin) and "honey-eater" (Slavic medved).[4] Thus some Indo-European language groups do not share the same PIE rootSony VAIO PCG-41111V battery. The theory of the bear taboo is taught to almost all beginning students of Indo-European and historical linguistics; the putative original PIE word for bear is itself descriptive, because a cognate word in Sanskrit is rakṣas, meaning "harm, injury".[5]

Evolutionary history

The family Ursidae is one of nine families in the suborder Caniformia, or "doglike" carnivores, within the order Carnivora. Bears' closest living relatives are the pinnipeds and musteloids. Sony VAIO PCG-41112M battery

The following synapomorphic (derived) traits set bears apart from related families:

presence of an alisphenoid canal

paroccipital processes that are large and not fused to the auditory bullae

auditory bullae are not enlarged

lacrimal bone is vestigial

cheek teeth are bunodont and hence indicative of a broad, hypocarnivorous (non-strictly meat-eating) diet (although hypercarnivorous (strictly meat-eating) taxa are known from the fossil record) Sony VAIO PCG-41111M battery

carnassials are flattened

Additionally, members of this family possess posteriorly oriented M2 postprotocrista molars, elongated m2 molars, and a reduction of the premolars.

Modern bears comprise eight species in three subfamilies: Ailuropodinae (monotypic with the giant panda), Tremarctinae (monotypic with the Spectacled Bear), and Ursinae (containing six species divided into one to three genera, depending upon authority) SONY VAIO PCG-21214V battery.

Fossil bears

The earliest members of Ursidae belong to the extinct subfamily Amphicynodontinae, including Parictis (late Eocene to early middle Miocene, 38–18 million years (Ma) ago) and the slightly younger Allocyon (early Oligocene, 34–30 Ma), both from North America. These animals looked very different from today's bears, being small and raccoon-like in overall appearanceSONY VAIO PCG-21213V battery, and a diet perhaps more similar to that of a badger. Parictis does not appear in Eurasia and Africa until the Miocene.[8] It is unclear whether late Eocene ursids were also present in Eurasia, although faunal exchange across the Bering land bridge may have been possible during a major sea level low stand as early as the late Eocene (~37 Ma) and continuing into the early Oligocene. SONY VAIO PCG-21212V batteryEuropean genera morphologically very similar to Allocyon, and also the much younger American Kolponomos (~18 Ma), are known from the Oligocene, including Amphicticeps and Amphicynodon.

Plithocyon armagnacensis skull

The raccoon-sized, dog-like Cephalogale is the oldest-known member of the subfamily Hemicyoninae which first appeared during the middle Oligocene in Eurasia ~30 Ma ago. The subfamily also includes the younger genera Phoberocyon (~ 20–15 Ma), and Plithocyon (~ 15–7 Ma) SONY VAIO PCG-21212M battery.

A Cephalogale-like species gave rise to the genus Ursavus during the early Oligocene (30–28 Ma); this genus proliferated into many species in Asia and is ancestral to all living bears. Species of Ursavus subsequently entered North America together with Amphicynodon and Cephalogale during the early Miocene (21–18 Ma) SONY VAIO PCG-21211M battery.

Members of living lineages of bears diverged from Ursavus ~20 Ma ago, likely via the species Ursavus elmensis. Based on genetic and morphological data, the subfamily Ailuropodinae (pandas) was the first to diverge from other living bears ~19 Ma ago, although no fossils of this group have been found pre-dating about 5 Ma. SONY VAIO PCG-51212M battery

The New World short-faced bears (Tremarctinae) differentiated from Ursinae following a dispersal event into North America during the mid Miocene (~13 Ma).[10] They invaded South America (~1 Ma) following formation of the Isthmus of Panama.[11] Their earliest fossil representative is Plionarctos in North America (~ 10–2 Ma). This genus is probably the direct ancestor to the North American short-faced bears (genus Arctodus) SONY VAIO PCG-51211M battery, the South American short-faced bears (Arctotherium), and the spectacled bears, Tremarctos, represented by both an extinct North American species (T. floridanus), and the lone surviving representative of the Tremarctinae, the South American spectacled bear (T. ornatus).

Fossil of Cave bear (Ursus spelaeus)

The subfamily Ursinae experienced a dramatic proliferation of taxa ~5.3–4.5 Ma ago coincident with major environmental changes, with the first members of the genus Ursus also appearing around this time. SONY VAIO PCG-51112M battery The sloth bear is a modern survivor of one of the earliest lineages to diverge during this radiation event (~5.3 Ma); it took on its peculiar morphology related to its diet on termites and ants no later than by the early Pleistocene. By 3–4 Ma ago, the species Ursus minimus appears in the fossil record of Europe, which apart from size is nearly identical to today's Asiatic black bearSONY VAIO PCG-51111M battery. It is likely ancestral to all bears within Ursinae, perhaps aside from the sloth bear. Two lineages evolved from U. minimus, the black bears (including the sun bear, the Asiatic black bear, and the American black bear), and the brown bears. Modern brown bears evolved from U. minimus via Ursus etruscus, which itself is ancestral to both the extinct Pleistocene cave bear and today's brown and polar bearsSONY VAIO PCG-51111V battery. Species of Ursinae have migrated repeatedly into N. America from Eurasia as early as 4 Ma ago during the early Pliocene.[12]

The fossil record of bears is exceptionally good. Direct ancestor-descendent relationships between individual species are often fairly well established, with sufficient intermediate forms known to make the precise cut-off between an ancestral and its daughter species subjective. SONY VAIO PCG-81211V battery

Other extinct bear genera include Agriarctos, Indarctos, and Agriotherium (sometimes placed within hemicyonids).

Taxonomic revisions of living bear species

The giant panda's taxonomy (subfamily Ailuropodinae) has long been debated. Its original classification by Armand David in 1869 was within the bear genus Ursus, but in 1870 it was reclassified by Alphonse Milne-Edwards to the raccoon family. SONY VAIO PCG-81111V battery In recent studies, the majority of DNA analyses suggest that the giant panda has a much closer relationship to other bears and should be considered a member of the family Ursidae.[15] Estimates of divergence dates place the giant panda as the most ancient offshoot among living taxa within Ursidae, having split from other bears 17.9 to 22.1 Ma ago.[10] The red panda was included within Ursidae in the pastSONY VAIO PCG-81212M battery. However, more recent research does not support such a conclusion and instead places it in its own family Ailuridae, in superfamily Musteloidea along with Mustelidae, Procyonidae, and Mephitidae. Multiple similarities between the two pandas, including the presence of false thumbs, are thus thought to represent an example of convergent evolution for feeding primarily on bambooSony VAIO PCG-81112M battery.

There is also evidence that, unlike their neighbors elsewhere, the brown bears of Alaska's ABC islands are more closely related to polar bears than they are to other brown bears in the world. Researchers Gerald Shields and Sandra Talbot of the University of Alaska Fairbanks Institute of Arctic Biology studied the DNA of several samples of the species and found that their DNA is different from that of other brown bearsSONY VAIO PCG-71111M battery. The researchers discovered that their DNA was unique compared to brown bears anywhere else in the world. The discovery has shown that while all other brown bears share a brown bear as their closest relative, those of Alaska's ABC Islands differ and share their closest relation with the polar bear.[19] There is also the very rare Tibetan blue bear, which is a type of brown bear. This animal has never been photographedSONY VAIO PCG-7192V battery.

Koalas are often referred to as bears due to their appearance; they are not bears, however, but marsupials.

Biology

Morphology

Despite being quadrupeds, bears can stand and sit similarly to humans.

Unlike other carnivora, bears have plantigrade hind feet

Bears are generally bulky and robust animals with relatively short legs. Bears are sexually dimorphic with regard to size, with the males being larger. Larger species tend to show increased levels of sexual dimorphism in comparison to smaller species, and where a species varies in size across its distribution individuals from larger sized areas tend also to vary moreSONY VAIO PCG-7191V battery. Bears are the most massive terrestrial members of the order Carnivora, with some Polar Bears and Brown Bears weighing over 750 kilograms (1,700 lb). As to which species is the largest may depend on whether the assessment is based on which species has the largest individuals (brown bears) or on the largest average size (polar bears). The smallest bears are the Sun Bears of Asia, which weigh an average of 65 kilograms (140 lb) for the males and 45 kilograms (99 lb) for the females. SONY VAIO PCG-7196M battery

Unlike other land carnivorans, bears are plantigrade. They distribute their weight toward the hind feet which makes them look lumbering when they walk. They are still quite fast with the brown bear reaching 30 miles per hour (48 km/h) although they are still slower than felines and canines. Bears can stand on their hind feet and sit up straight with remarkable balanceSONY VAIO PCG-7195M battery. Bears have non-retractable claws which are used for digging, climbing, tearing and catching prey. Their ears are rounded.

Bears have an excellent sense of smell, a better sense of smell than the dogs (Canidae), or possibly any other mammal. This sense of smell is used for signalling between bears (either to warn off rivals or detect mates) and for finding food. Smell is the principal sense used by bears to find most of their diet. SONY VAIO PCG-7194M battery

Dentition

Unlike most other members of the Carnivora, bears have relatively undeveloped carnassial teeth, and their teeth are adapted for a diet that includes a significant amount of vegetable matter. The canine teeth are large, and the molar teeth flat and crushing. There is considerable variation in dental formula even within a given species. It has been suggested that this indicates bears are still in the process of evolving from a carnivorous to a predominantly herbivorous dietSONY VAIO PCG-7192M battery. Polar bears appear to have secondarily re-evolved fully functional carnassials, as their diet has switched back towards carnivory.[21] The dental formula for living bears is:

Distribution and habitat

The bears are mostly found in the northern hemisphere, with a single species, the spectacled bear, occurring in South America. The Atlas Bear, a subspecies of the Brown Bear, was the only bear native to Africa. It was distributed in North Africa from Morocco to Libya, but has been extinct since around the 1870sSONY PCG-8113M battery. All the other species are found in North America, Asia and Europe. The most widespread species is the Brown Bear, which occurs from Western Europe eastwards through Asia to the western areas of North America. The American Black Bear is restricted to North America, and the Polar bear is restricted to the Arctic Sea. All the remaining species are Asian.SONY PCG-8112M battery

With the exception of the Polar Bear the bears are mostly forest species. Some species, particularly the Brown Bear, may inhabit or seasonally use other areas such as alpine scrub or tundra.

Behaviour

While many people think that bears are nocturnal, they are in fact generally diurnal, active for the most part during the day. The belief that they are nocturnal apparently comes from the habits of bears that live near humans which engage in some nocturnal activitiesSONY PCG-7134M battery, such as raiding trash cans or crops while avoiding humans. The sloth bear of Asia is the most nocturnal of the bears, but this varies by individual and females with cubs are often diurnal in order to avoid competition with males and nocturnal predators.[20] Bears are overwhelmingly solitary and are considered to be the most asocial of all the Carnivora. Liaisons between breeding bears are briefSONY PCG-7131M battery, and the only times bears are encountered in small groups are mothers with young or occasional seasonal bounties of rich food (such as salmon runs).[20]

Vocalizations

Bears produce a variety of vocalizations such as:

Moaning: produced mostly as mild warnings to potential threats or in fear.

Barking: produced during times of alarm, excitement or to give away the animal's position.

Huffing: made during courtship or between mother and cubs to warn of danger.

Growling: produced as strong warnings to potential threats or in anger.

Roaring: used much for the same reasons as growls and also to proclaim territory and for intimidationSONY PCG-7122M battery.

Diet and interspecific interactions

Asian black bear feeding on berries

Brown bears make use of infrequent but predictable salmon runs in order to feed

Their carnivorous reputation non-withstanding, most bears have adopted a diet of more plant than animal matter and are completely opportunistic omnivores. Some bears will climb trees in order to obtain mast (edible vegatative or reproductive parts such as acorns) SONY PCG-7121M battery ; smaller species which are more able to climb include a greater amount of this in their diet.[22] Such masts can be very important to the diet of these species, and mast failures may result in long range movements by bears looking for alternative sources of food.[23] One exception is the polar bear, which has adopted a diet mainly of marine mammals to survive in the Arctic. The other exception is the giant panda which has adopted a diet mainly of bambooSONY PCG-7113M battery. Stable isotope analysis of the extinct giant short-faced bear (Arctodus simus) shows that it was also an exclusive meat eater, probably a scavenger.[24] The sloth bear, though not as specialized as the previous two species, has lost several front teeth usually seen in bears and developed a long, suctioning tongue in order to feed on the ants, termites and other burrowing insects that they favourSONY PCG-7112M battery. At certain times of the year these insects can make up 90% of their diet.[25] All bears will feed on any food source that becomes available, and the nature of that varies seasonally. A study of Asiatic black bears in Taiwan found that they would consume large numbers of acorns when they were most common, and switch to ungulates in other times of the year. SONY PCG-8Z3M battery

When taking warm-blooded animals, bears will typically take small or young animals, as they are easier to catch. Although (besides polar bears) both species of black bear and the brown bear can sometimes take large prey, such as ungulates.[26][27] Often, bears will feed on other large animals when they encounter a carcass, whether or not the carcass is claimed by or is the kill of another predatorSONY PCG-8Z2M battery. This competition is the main source of interspecies conflict. Bears are typically the apex predators in their range due to their size and power, and can defend a carcass against nearly all comers. Mother bears also can usually defend their cubs against other predators. The tiger is the only known predator known to regularly prey on adult bears, including sloth bears, Asiatic black bears, giant pandas, sun bears and small brown bearsSONY PCG-8Z1M battery .

Breeding

Bear cubs, like this American Black Bear, are sometimes killed by males

The age at which bears reach sexual maturity is highly variable, both between and within species. Sexual maturity is dependent on body condition, which is in turn dependent upon the food supply available to the growing individual. In the females of smaller species may have young in as little as two yearsSONY PCG-8Y3M battery, whereas the larger species may not rear young until they are four or even nine years old. First breeding may be even later in males, where competition for mates may leave younger males without access to females.[20]

American Black Bears mating

The bear's courtship period is very brief. Bears in northern climates reproduce seasonally, usually after a period of inactivity similar to hibernation, although tropical species breed all year round. Cubs are born toothless, blind, and baldSONY PCG-8Y2M battery. The cubs of brown bears, usually born in litters of 1–3, will typically stay with the mother for two full seasons. They feed on their mother's milk through the duration of their relationship with their mother, although as the cubs continue to grow, nursing becomes less frequent and cubs learn to begin hunting with the mother. They will remain with the mother for approximately three yearsSONY PCG-7Z1M battery, until she enters the next cycle of estrus and drives the cubs off. Bears will reach sexual maturity in five to seven years. Male bears, especially Polar and Brown Bears, will kill and sometimes devour cubs born to another father in order to induce a female to breed again. Female bears are often successful in driving off males in protection of their cubs, despite being rather smallerSONY PCG-6W2M battery.

Winter dormancy

Polar bearmother is nursing her cub

Polar bear at Wapusk National Park, Canada

Many bears of northern regions are assumed[by whom?] to hibernate in the winter. While many bear species[which?] do go into a physiological state often colloquially called "hibernation" or "winter sleep", it is not true hibernation. In true hibernators, body temperatures drop to near ambient and heart rate slows drasticallySONY PCG-5J5M battery, but the animals periodically rouse themselves to urinate or defecate and to eat from stored food. The body temperature of bears, on the other hand, drops only a few degrees from normal and heart rate slows only slightly. They normally do not wake during this "hibernation", and therefore do not eat, drink, urinate or defecate the entire periodSONY PCG-5K2M battery . Higher body heat and being easily roused may be adaptations, because females give birth to their cubs during this winter sleep.

Relationship with humans

See also: Bear danger

Some species, such as the polar bear, American black bear, sloth bear and the brown bear, are dangerous to humans, especially in areas where they have become used to people. All bears are physically powerful and are likely capable of fatally attacking a person, but theySONY PCG-5K1M battery, for the most part, are shy, are easily frightened and will avoid humans. Injuries caused by bears are rare, but are often widely reported.[28] The danger that bears pose is often vastly exaggerated, in part by the human imagination. However, when a mother feels her cubs are threatened, she will behave ferociously. It is recommended to give all bears a wide berth because they are behaviorally unpredictableSONY PCG-5J4M battery.

Bears may also come into conflict with humans where they raid crops or attack livestock.[29][30] These problems may be the work of only a few bears but create a climate of conflict as farmers and ranchers may perceive all losses as due to bears and advocate the preventive removal of all bears.[30] Mitigation methods may be used to reduce bear damage to crops, and reduce local antipathy towards bears. SONY PCG-5J1M battery

Bear danger area closure sign of a type used in Denali National Park in Alaska

Wojtek with Polish soldier. During the Battle of Monte Cassino, Wojtek helped move ammunition.

Laws have been passed in many areas of the world to protect bears from hunters' habitat destruction. Public perception of bears is often very positive, as people identify with bears due to their omnivorous diet, ability to stand on two legs, and symbolic importance, SONY PCG-5G2M battery and there is widespread support for bear protection, at least in more affluent societies.[32] In more rural and poorer regions attitudes may be more shaped by the dangers posed by bears and the economic costs that they incur to farmers and ranchers.[30] Some populated areas with bear populations have also outlawed the feeding of bears, including allowing them access to garbage or other food wasteSony VAIO PCG-8131M battery. Bears in captivity have been trained to dance, box, or ride bicycles; however, this use of the animals became controversial in the late 20th century. Bears were kept for baiting in Europe at least since the 16th century.

Bear hunt

Some cultures use bears for food and folk medicine. Their meat is dark and stringy, like a tough cut of beef. In Cantonese cuisine, bear paws are considered a delicacySony VAIO PCG-8152M battery. The peoples of China, Japan, and Korea use bears' body parts and secretions (notably their gallbladders and bile) as part of traditional Chinese medicine. It is believed more than 12,000 bile bears are kept on farms, farmed for their bile, in China, Vietnam and South Korea.[33] Bear meat must be cooked thoroughly as it can often be infected with Trichinella spiralis, which can cause trichinosis. Sony VAIO PCG-31311M battery

Culture

Names

The female first name "Ursula", originally derived from a Christian saint's name and common in English- and German-speaking countries, means "little she-bear" (diminutive of Latin ursa). In Switzerland the male first name "Urs" is especially popular, while the name of the canton and city of Bern is derived from Bär, German for bearSony VAIO PCG-31111M battery.

In Scandinavia, the male personal names Björn (Sweden, Iceland) and Bjørn (Norway, Denmark) meaning "bear" are relatively common. In Finland, male personal name Otso is an old poetic name for bear, similar to Kontio.

In Russian and other Slavic languages, the word for bear, "Medved" (медведь), and variants or derivatives such as Medvedev, are common surnamesSony VAIO PCG-8112M battery.

The Irish family name "McMahon" means "Son of Bear" in Irish.

In East European Jewish communities, the name "Ber" (בער)—Yiddish cognate of "Bear"—has been attested as a common male first name, at least since the 18th century, and was among others the name of several prominent Rabbis. The Yiddish "Ber" is still in use among Orthodox Jewish communities in Israel, the US and other countriesSony VAIO PCG-7186M battery. With the transition from Yiddish to Hebrew under the influence of zionism, the Hebrew word for "bear", "Dov" (דב), was taken up in contemporary Israel and is at present among the commonly used male first names in that country.

"Ten Bears" (Paruasemana) was the name of a well-known 19th century chieftain among the Comanche. Also among other Native American tribes, bear-related names are attestedSony VAIO PCG-7171M battery.

Myth and legend

For bears in mythology, see Jean de l'Ours, Arcturus, Ursa Major, and Berserker.

There is evidence of prehistoric bear worship. Anthropologists such as Joseph Campbell have regarded this as a common feature in most of the fishing and hunting-tribes. The prehistoric Finns, along with most Siberian peoples, considered the bear as the spirit of one's forefathersSony VAIO PCG-9Z1M battery. This is why the bear (karhu) was a greatly respected animal, with several euphemistic names (such as otso, mesikämmen and kontio). The bear is the national animal of Finland.

This kind of attitude is reflected in the traditional Russian fairy tale "Morozko", whose arrogant protagonist Ivan tries to kill a mother bear and her cubs—and is punished and humbled by having his own head turned magically into a bear's head and being subsequently shunned by human societySony VAIO PCG-5S1M battery.

"The Brown Bear of Norway" is a Scottish fairy tale telling the adventures of a girl who married a prince magically turned into a bear, and who managed to get him back into a human form by the force of her love and after many trials and difficulties. In the 1970s this story was adapted into the East German fantasy film The Singing Ringing Tree and broadcast on British televisionSony VAIO PCG-5P1M battery.

There has been evidence about early bear worship in China and among the Ainu culture as well (see Iomante). Korean people in their mythology identify the bear as their ancestor and symbolic animal. According to the Korean legend, a god imposed a difficult test on a she-bear, and when she passed it the god turned her into a woman and married herSony VAIO PCG-5N2M battery.

Legends of saints taming bears are common in the Alpine zone. In the arms of the bishopric of Freising (see illustration) the bear is the dangerous totem animal tamed by St. Corbinian and made to carry his civilised baggage over the mountains. A bear also features prominently in the legend of St. Romedius, who is also said to have tamed one of these animals and had the same bear carry him from his hermitage in the mountains to the city of TrentoSony VAIO PCG-3C2M battery.

Similar stories are told of Saint Gall and Saint Columbanus.

This recurrent motif was used by the Church as a symbol of the victory of Christianity over Paganism.[37] In the Norse settlements of northern England during the tenth century a type of "hogback" grave cover of a long narrow block of stone with a shaped apex like the roof beam of a long house, is carved with a muzzled, thus ChristianisedSony VAIO PCG-8161M battery, bear clasping each gable end. Though the best collection of these is in the church at Brompton, North Yorkshire,[38] their distribution ranges across northern England and southern Scotland, with a scattered few in the north Midlands and single survivals in Wales, Cornwall and Ireland; a late group is found in the Orkney IslandsSony VAIO PCG-8141M battery.

Bears are a popular feature of many children's stories including Goldilocks and The Story of the Three Bears, the Berenstein Bears, and Winnie the Pooh.

Symbolic use

For more details on this topic, see Bears in heraldry.

The British Lion, the Persian Cat and the Russian Bear (see The Great Game)

The Russian bear is a common national personification for Russia (as well as the Soviet Union). The brown bear is also Germany's and Finland's national animal.

The flag of CaliforniaSony VAIO PCG-3J1M battery

In the United States, the black bear is the state animal of Louisiana, New Mexico, and West Virginia; the grizzly bear is the state animal of both Montana and California. Bears also appear in the state seals of California and Missouri.

In the UK, the bear and staff has long featured on the heraldic arms of Warwickshire county.[39]

Bears appear in the canting arms of Bern and BerlinSony VAIO PCG-3H1M battery.

Also, "bear", "bruin", or specific types of bears are popular nicknames or mascots, for example, for sports teams (Chicago Bears, California Golden Bears, UCLA Bruins, Boston Bruins); and a bear cub called Misha was mascot of the 1980 Summer Olympics in Moscow, USSR.

Smokey Bear

Smokey Bear has become a part of American culture since his introduction in 1944. Known to almost all AmericansSony VAIO PCG-3F1M battery, he and his message, "Only you can prevent forest fires" (updated in 2001 to "Only you can prevent wildfires"), have been a symbol of preserving woodlands.[40] Smokey wears a hat similar to one worn by U.S. Forest Service rangers; state police officers in some states wear a similar style, giving rise to the CB slang "bear" or "Smokey" for the highway patrol.

The name Beowulf has been hypothesized to mean "bee-wolf", a kenning for "bear".
Sony VAIO PCG-3C1M battery

Figures of speech

The physical attributes and behaviours of bears are commonly used in figures of speech in English.

In the stock market, a bear market is a period of declining prices. Pessimistic forecasting or negative activity is said to be bearish (due to the stereotypical posture of bears looking downwards), and one who expresses bearish sentiment is a bear. Its opposite is a bull market, and bullish sentiment from bullsSony VAIO PCG-9Z2L battery.

In gay slang, the term "bear" refers to male individuals who possess physical attributes much like a bear, such as a heavy build, abundant body hair, and commonly facial hair.

A bear hug is typically a tight hug that involves wrapping one's arms around another person, often leaving that person's arms immobile. It was used in the Ronald Reagan political ad "Bear in the woods"Sony VAIO PCG-9Z1L battery.

Bear tracking – in the old Western states of the U.S. and, to this day, in the former Dakota Territory, the expression "you ain't just a bear trackin'" is used to mean "you ain't lying" or "that's for sure". This expression evolved as an outgrowth of the experience pioneer hunters and mountainmen had when tracking bear. Bears often lay down false tracks and are notorious for doubling back on anything tracking themSony VAIO PCG-9131L battery. If you are not following bear tracks, you are not following false trails or leads in your thoughts, words or deeds.

In Korean culture a person is referred to as being "like a bear" when they are stubborn or not sensitive to what is happening around their surroundings. Used as a phrase to call a person "stubborn bear"Sony VAIO PCG-8161L battery.

The Bible compares King David's "bitter warriors", who fight with such fury that they could overcome many times their number of opponents, with "a bear robbed of her whelps in the field" (2 Samuel 17:8 s:Bible (King James)/2 Samuel#Chapter 17). The phrase "a bereaved bear" (דב שכול), derived from this Biblical source, is still used in the literary Hebrew of contemporary IsraelSony VAIO PCG-8152L battery.

The hippopotamus (Hippopotamus amphibius), or hippo, from the ancient Greek for "river horse" (ἱπποπόταμος), 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.) After the elephant and rhinoceros, the hippopotamus is the third largest land mammal and the heaviest extant artiodactylSony VAIO PCG-8141L battery.

The hippopotamus is semi-aquatic, inhabiting rivers, lakes and mangrove swamps, 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 landSony VAIO PCG-8131L battery.

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 fossilsSony VAIO PCG-81312L battery, 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 the three species of elephant (3 to 9 tonnes) Sony VAIO PCG-81214L battery. The hippopotamus is one of the largest quadrupeds (four legged mammals) [5] and 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 one of the most dangerous animals in AfricaSony VAIO PCG-81214L battery. 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. There is also a colony of non-zoo hippos in Colombia introduced by Pablo EscobarSony VAIO PCG-81114L battery.

Etymology

Look up hippopotamus in Wiktionary, the free dictionary.

The word "hippopotamus" is derived from the ancient Greek ἱπποπόταμος, hippopotamos, from ἵππος, hippos, "horse", and ποταμός, potamos, "river", meaning "horse of the river".[6] In English, the plural is hippopotamuses, but hippopotami is also used; hippos can be used as a short plural. Hippopotamuses are gregarious, living in groups of up to 30 animalsSony VAIO PCG-81113L battery; such a name is called a pod, herd, dale, or bloat.

In Africa, the hippo is known by several names including Kiboko (Swahili), Ensherre (Nkore), Tomondo (Turu), Nvubu (Luganda), Ifuru (Luhya), Emiria (Ateso), Magawit (Sebei), Kibei (Kalenjin), Olmakau (Maasai) and Jir (Somali) in the east;[8]:256 and Seekoei (Afrikaans), Mvuvu (Venda), Kubu (Lozi) and Mvubu (Xhosa, Siswati and Zulu) in the south.Sony VAIO PCG-7142L battery

Taxonomy and origins

Classification

The hippopotamus is the type genus of the family Hippopotamidae. The Pygmy Hippopotamus belongs to a different genus in Hippopotamidae, either Choeropsis or Hexaprotodon. Hippopotamidae are sometimes known as Hippopotamids. Sometimes the sub-family Hippopotaminae is used. Further, some taxonomists group hippopotamuses and anthracotheres in the super-family Anthracotheroidea or HippopotamoideaSony VAIO PCG-7141L battery.

A pygmy hippopotamus (Hexaprotodon liberiensis)

Hippopotamidae are classified along with other even-toed ungulates in the order Artiodactyla. Other artiodactyls include camels, cows, deer and pigs, although hippopotamuses are not closely related to these groups.

Five subspecies of hippos have been described based on morphological differences in their skulls and geographical differences: Sony VAIO PCG-71111L battery

H. a. amphibius – (the nominate subspecies) which stretched from Egypt, where they are now extinct, south up the Nile River to Tanzania and Mozambique.

H. a. kiboko – in the Horn of Africa, in Kenya and Somalia. Broader nasals and more hollowed interorbital region.

H. a. capensis – from Zambia to South Africa. Most flattened skull of the subspecies.

H. a. tschadensis – throughout Western Africa to, as the name suggests, Chad. Slightly shorter and wider face, with prominent orbitsSony VAIO PCG-61411L battery.

H. a. constrictus – in Angola, the southern Democratic Republic of Congo and Namibia. Named for its deeper preorbital constriction.

The suggested subspecies were never widely used or validated by field biologists; the described morphological differences were small enough that they could have resulted from simple variation in non-representative samples.Sony VAIO PCG-61112L batteryGenetic analyses have tested the existence of three of these putative subspecies. A study examining mitochondrial DNA from skin biopsies taken from 13 sampling locations, considered genetic diversity and structure among hippo populations across the continent. The authors found low but significant genetic differentiation among H. a. amphibius, H. a. capensis, and H. a. kiboko. Neither H.a.tschadensis nor H.a.constrictus have been tested.Sony VAIO PCG-61111L battery

[edit]Evolution

Until 1909, naturalists grouped hippos with pigs, based on molar patterns. Several lines of evidence, first from blood proteins, then from molecular systematics[14] and DNA and the fossil record, show that their closest living relatives are cetaceans—whales, dolphins and porpoises. The common ancestor of hippos and whales branched off from Ruminantia and the rest of the even-toed ungulatesSony VAIO PCG-5T4L battery; the cetacean and hippo lineages split soon afterwards.

The most recent theory of the origins of Hippopotamidae suggests that hippos and whales shared a common semi-aquatic ancestor that branched off from other artiodactyls around 60 million years ago.[15][17] This hypothesized ancestral group likely split into two branches around 54 million years ago.[14] One branch would evolve into cetaceansSony VAIO PCG-5T3L battery, possibly beginning about 52 million years ago with the proto-whale Pakicetus and other early whale ancestors collectively known as Archaeoceti, which eventually underwent aquatic adaptation into the completely aquatic cetaceans.[19]

Hippopotamus madagascariensis skeleton with a modern hippopotamus skullSony VAIO PCG-5T2L battery.

The other branch became the anthracotheres, a large family of four-legged beasts, the earliest of whom in the late Eocene would have resembled skinny hippopotamuses with comparatively small and narrow heads. All branches of the anthracotheres, except that which evolved into Hippopotamidae, became extinct during the Pliocene without leaving any descendants. Sony VAIO PCG-5S3L battery

A rough evolutionary lineage can be traced from Eocene and Oligocene species: Anthracotherium and Elomeryx to the Miocene Merycopotamus and Libycosaurus and the very latest anthracotheres in the Pliocene.[20] Merycopotamus, Libycosaurus and all hippopotamids can be considered to form a clade, with Libycosaurus being more closely related to hipposSony VAIO PCG-5S2L battery. Their common ancestor would have lived in the Miocene, about 20 million years ago.

Hippopotamids are therefore deeply nested within the family Anthracotheriidae. The Hippopotamidae are believed to have evolved in Africa; the oldest known hippopotamid is the genus Kenyapotamus which lived in Africa from 16 to 8 million years ago. While hippopotamid species spread across Asia and EuropeSony VAIO PCG-5S1L battery, no hippopotamuses have ever been discovered in the Americas, although various anthracothere genera emigrated into North America during the early Oligocene. From 7.5 to 1.8 million years ago an ancestor to the modern hippopotamus, Archaeopotamus, lived in Africa and the Middle East.[21]

While the fossil record of hippos is still poorly understood, the two modern genera, Hippopotamus and Choeropsis (sometimes Hexaprotodon) Sony VAIO PCG-5R2L battery, may have diverged as far back as 8 million years ago. Taxonomists disagree whether or not the modern Pygmy Hippopotamus is a member of Hexaprotodon —an apparently paraphyletic genus also embracing many extinct Asian hippopotamuses that is more closely related to Hippopotamus, or Choeropsis —an older and basal genus. Sony VAIO PCG-5R1L battery

Extinct species

Three species of Malagasy Hippopotamus became extinct during the Holocene on Madagascar, one of them within the past 1,000 years. The Malagasy Hippos were smaller than the modern hippopotamus, likely through the process of insular dwarfism.[22] There is fossil evidence that many Malagasy Hippos were hunted by humans, a likely factor in their eventual extinction. Sony VAIO PCG-5P4L battery Isolated members of Malagasy Hippopotamus may have survived in remote pockets; in 1976, villagers described a living animal called the Kilopilopitsofy, which may have been a Malagasy Hippopotamus.[23]

Two species of Hippopotamus, the European Hippopotamus (H. antiquus) and H. gorgops ranged throughout continental Europe and the British Isles. Both species became extinct before the last glaciationSony VAIO PCG-5P2L battery. Ancestors of European Hippos found their way to many islands of the Mediterranean during the Pleistocene.[24] Both species were larger than the modern hippopotamus, averaging about 1 meter (3.3 feet) longer.

The Pleistocene also saw a number of dwarf species evolve on several Mediterranean islands including Crete (H. creutzburgi), Cyprus (H. minor), Malta (H. melitensis) and Sicily (H. pentlandi). Of these, the Cyprus Dwarf HippopotamusSony VAIO PCG-5N4L battery, survived until the end of the Pleistocene or early Holocene. Evidence from an archaeological site Aetokremnos, continues to cause debate on whether or not the species was encountered, and was driven to extinction, by man.

Description

A hippo's skull, showing the large canine teeth used for fighting

Hippopotamuses are among the largest living mammals; only elephants and some rhinoceroses and whales are heavier. They can live in the water or on landSony VAIO PCG-5N2L battery. Their specific gravity allows them to sink and walk or run along the bottom of a river. Hippos are considered megafauna, but unlike all other African megafauna, hippos have adapted for a semi-aquatic life in freshwater lakes and rivers.[11]:3

Because of their enormous size, hippopotamuses are difficult to weigh in the wild. Most estimates of the weight come from culling operations that were carried out in the 1960sSony VAIO PCG-51513L battery. The average weights for adult males ranged between 1,500–1,800 kg (3,300–4,000 lb). Females are smaller than their male counterparts, with average weights measuring between 1,300–1,500 kg (2,900–3,300 lb). Older males can get much larger, reaching at least 3,200 kg (7,100 lb) and occasionally weighing 4,500 kg (9,900 lb). Male hippos appear to continue growing throughout their lives; females reach a maximum weight at around age 25. Sony VAIO PCG-51511L battery

Hippos measure 3.3 to 5.2 meters (11 to 17 ft) long, including a tail of about 56 centimeters (22 in) in length and average about 1.5 meters (5 ft) tall at the shoulder.[29][30] The range of hippopotamus sizes overlaps with the range of the White Rhinoceros; use of different metrics makes it unclear which is the largest land animal after elephantsSony VAIO PCG-51412L battery. Even though they are bulky animals, hippopotamuses can run faster than a human on land. Estimates of their running speed vary from 30 km/h (18 mph) to 40 km/h (25 mph), or even 50 km/h (30 mph). The hippo can maintain these higher speeds for only a few hundred meters. Despite being semi-aquatic and having webbed feet, an adult hippo is not a particularly good swimmer nor can it floatSony VAIO PCG-51411L battery. It is rarely found in deep water; when it is, the animal moves by porpoise-like leaps from the bottom.[11]:3

An open mouth signals that the hippo feels threatened.

The eyes, ears, and nostrils of hippos are placed high on the roof of the skull. This allows them to be in the water with most of their body submerged in the waters and mud of tropical rivers to stay cool and prevent sunburn. Their skeletal structure is graviportalSony VAIO PCG-51312L battery, adapted to carrying the animals' enormous weight. Hippopotamuses have small legs (relative to other megafauna) because the water in which they live reduces the weight burden. Unlike most other semi-aquatic animals, the hippopotamus has very little hair.[8]:260 The skin is 6 in (15 cm) thick,[31] providing it great protection against conspecifics and predatorsSony VAIO PCG-51311L battery. The animals's upper parts are purplish-gray to blue-black while the under parts and areas around the eyes and ears can be brownish-pink.[8]:260

The hippo's jaw is powered by a large masseter and a well developed digastric; the latter loops up behind the former to the hyoid.[8]:259 The animal has a distinctive gape, which can reach 150°.[31] On the National Geographic Channel television programSony VAIO PCG-51211L battery, "Dangerous Encounters with Brady Barr", Dr. Brady Barr measured the bite force of an adult female hippo at 8100 N (1821 lbf); Barr also attempted to measure the bite pressure of an adult male hippo, but had to abandon the attempt due to the male's aggressiveness.[32] Hippopotamus teeth sharpen themselves as they grind together. The lower canines and lower incisors are enlarged, especially in males, and grow continuously. The incisors can reach 40 cm (16 in) while the canines reach up to 50 cm (20 in). Sony VAIO PCG-41112L battery

Their skin secretes a natural sunscreen substance which is red-colored. The secretion is sometimes referred to as "blood sweat," but is neither blood nor sweat. This secretion is initially colorless and turns red-orange within minutes, eventually becoming brown. Two distinct pigments have been identified in the secretions, one red (hipposudoric acid) and one orange (norhipposudoric acid) Sony VAIO PCG-3A4L battery. The two pigments are highly acidic compounds. Both pigments inhibit the growth of disease-causing bacteria; as well, the light absorption of both pigments peaks in the ultraviolet range, creating a sunscreen effect. All hippos, even those with different diets, secrete the pigments, so it does not appear that food is the source of the pigments. Instead, the animals may synthesize the pigments from precursors such as the amino acid tyrosine. Sony VAIO PCG-3A3L battery

A hippo's lifespan is typically 40–50 years.[8]:277 Donna the Hippo, 60, is the oldest living hippo in captivity. She lives at the Mesker Park Zoo in Evansville, Indiana, USA.[34][35] The oldest hippo ever recorded was called Tanga; she lived in Munich, Germany, and died in 1995 at the age of 61. Sony VAIO PCG-3A2L battery

Distribution

Hippopotamus amphibius was widespread in North Africa and Europe during the Eemian[37] and late Pleistocene until about 30,000 years ago. The species was common in Egypt's Nile region until historic times but has since been extirpated. Pliny the Elder writes that, in his time, the best location in Egypt for capturing this animal was in the Saite nome; Sony VAIO PCG-3A1L battery the animal could still be found along the Damietta branch after the Arab Conquest in 639. Hippos are still found in the rivers and lakes of Uganda, Sudan, Somalia, Kenya, nor

thern Democratic Republic of the Congo and Ethiopia, west through Ghana to Gambia, and also in Southern Africa (Botswana, Republic of South Africa, Zimbabwe, Zambia). A separate population exists in Tanzania and MozambiqueSony VAIO PCG-394L battery.

[edit]Conservation status

The Hippopotamus Hunt (1617), by Peter Paul Rubens

Genetic evidence suggests that common hippos in Africa experienced a marked population expansion during or after the Pleistocene Epoch, attributed to an increase in water bodies at the end of the era. These findings have important conservation implications as hippo populations across the continent are currently threatened by loss of access to fresh water. Sony VAIO PCG-393L batteryHippos are also subject to unregulated hunting and poaching. In May 2006 the hippopotamus was identified as a vulnerable species on the IUCN Red List drawn up by the World Conservation Union (IUCN), with an estimated population of between 125,000 and 150,000 hippos, a decline of between 7% and 20% since the IUCN's 1996 study. Sony VAIO PCG-391L battery

The hippo population declined most dramatically in the Democratic Republic of the Congo.[39] The population in Virunga National Park had dropped to 800 or 900 from around 29,000 in the mid 1970s.[40] The decline is attributed to the disruptions caused by the Second Congo War.[40] The poachers are believed to be former Hutu rebelsSony VAIO PCG-384L battery, poorly paid Congolese soldiers, and local militia groups.[40] Reasons for poaching include the belief that hippos are harmful to society, and also for money.[41] The sale of hippo meat is illegal, but black-market sales are difficult for Virunga National Park officers to track.

[edit]Invasive potential

In the late 1980s, Pablo Escobar kept four hippos in a private menagerie at his residence in Hacienda Napoles, 100 km east of Medellín, Colombia, after buying them in New OrleansSony VAIO PCG-383L battery. They were deemed too difficult to seize and move after Escobar's fall, and hence left on the untended estate. By 2007, the animals had multiplied to 16 and had taken to roaming the area for food in the nearby Magdalena River.[42] In 2009, two adults and one calf escaped the herd, and after attacking humans and killing cattle, one of the adults (called "Pepe") was killed by hunters under authorization of the local authorities. Sony VAIO PCG-382L batteryIt is unknown what kind of effects the presence of hippos might have on the ecosystem in Colombia. According to experts interviewed by W Radio Colombia, the animals could survive in the Colombian jungles. It is believed that the lack of control from the Colombian government, which is not used to dealing with this species, could result in human fatalitiesSony VAIO PCG-381L battery.

Behavior

A bull hippo out of water during daylight

Hippos spend most of their days wallowing in the water or the mud, with the other members of their pod. The water serves to keep their body temperature down, and to keep their skin from drying out. With the exception of eating, most of hippopotamuses' lives —from childbirth, fighting with other hippos, to reproduction— occur in the waterSony VAIO PCG-7185L battery.

Hippos leave the water at dusk and travel inland, sometimes up to 8 kilometers (5 mi), to graze on short grass, their main source of food. They spend four to five hours grazing and can consume 68 kilograms (150 lb) of grass each night.[45] Like almost any herbivore, they will consume many other plants if presented with themSony VAIO PCG-7184L battery, but their diet in nature consists almost entirely of grass, with only minimal consumption of aquatic plants.[46] Hippos have (rarely) been filmed eating carrion, usually close to the water. There are other reports of meat-eating, and even cannibalism and predation.[47] The stomach anatomy of a hippo is not suited to carnivory, and meat-eating is likely caused by aberrant behavior or nutritional stress. Sony VAIO PCG-7183L battery

The diet of hippos consists mostly of terrestrial grasses, even though they spend most of their time in the water. Most of their defecation occurs in the water, creating allochthonous deposits of organic matter along the river beds. These deposits have an unclear ecological function.[46] Because of their size and their habit of taking the same paths to feedSony VAIO PCG-7182L battery, hippos can have a significant impact on the land they walk across, both by keeping the land clear of vegetation and depressing the ground. Over prolonged periods hippos can divert the paths of swamps and channels.[48]

Adult hippos move at speeds up to 8 km/h (5 mph) in water. Adult hippos typically resurface to breathe every three to five minutesSony VAIO PCG-7181L battery. The young have to breathe every two to three minutes.[11]:4 The process of surfacing and breathing is automatic, and even a hippo sleeping underwater will rise and breathe without waking. A hippo closes its nostrils when it submerges.

As with fish and turtles on a coral reef, hippo occasionally visit cleaning stations and signal by wide-open mouth their readiness for being cleaned of parasites by certain species of fishSony VAIO PCG-7174L battery. This situation is an example of mutualism in which the hippo benefits from the cleansing while the fish receive food.[49]

Social life

A hippopotamus pod

Studying the interaction of male and female hippopotamuses has long been complicated by the fact that hippos are not sexually dimorphic and thus females and young males are almost indistinguishable in the field.[50] Although hippos like to lie close to each other, they do not seem to form social bonds except between mothers and daughtersSony VAIO PCG-7173L battery, and are not social animals. The reason they huddle close together is unknown.[11]:49

Hippopotamuses are territorial only in water, where a bull presides over a small stretch of river, on average 250 meters in length, and containing ten females. The largest pods can contain over 100 hippos.[11]:50 Other bachelors are allowed in a bull's stretchSony VAIO PCG-7172L battery, as long as they behave submissively toward the bull. The territories of hippos exist to establish mating rights. Within the pods, the hippos tend to segregate by gender. Bachelors will lounge near other bachelors, females with other females, and the bull on his own. When hippos emerge from the water to graze, they do so individually. Sony VAIO PCG-7171L battery

Hippopotamuses appear to communicate verbally, through grunts and bellows, and it is thought that they may practice echolocation, but the purpose of these vocalizations is currently unknown. Hippos have the unique ability to hold their head partially above the water and send out a cry that travels through both water and air; hippos above and under water will respond. Sony VAIO PCG-7162L battery

Reproduction

Hippos are born underwater.

Female hippos reach sexual maturity at five to six years of age and have a gestation period of 8 months. A study of endocrine systems revealed that female hippopotamuses may begin puberty as early as 3 or 4 years of age.[52] Males reach maturity at around 7.5 years.

A study of hippopotamus reproductive behavior in Uganda showed that peak conceptions occurred during the end of the wet season in the summerSony VAIO PCG-7161L battery, and peak births occurred toward the beginning of the wet season in late winter. This is because of the female's estrous cycle; as with most large mammals, male hippopotamus spermatozoa is active year round. Studies of hippos in Zambia and South Africa also showed evidence of births occurring at the start of the wet season. After becoming pregnant, a female hippopotamus will typically not begin ovulation again for 17 months. Sony VAIO PCG-7154L battery

Mating occurs in the water with the female submerged for most of the encounter,[11]:63 her head emerging periodically to draw breath. Hippos are one of the few mammals that give birth under water, along with Cetaceans and Sirenians (manatees and dugongs). Baby hippos are born underwater at a weight between 25 and 45 kg (60–110 lb) and an average length of around 127 cm (50 in) and must swim to the surface to take their first breathSony VAIO PCG-7153L battery. A mother typically gives birth to only one hippo, although twins also occur. The young often rest on their mothers' backs when in water that is too deep for them, and they swim underwater to suckle. They also will suckle on land when the mother leaves the water. Weaning starts between six and eight months after birth and most calves are fully weaned after a year. Sony VAIO PCG-7152L battery

Like many other large mammals, hippos are described as K-strategists, in this case typically producing just one large, well-developed infant every couple of years (rather than large numbers of small, poorly developed young several times per year as is common among small mammals such as rodents). Sony VAIO PCG-7151L battery

Aggression

Male hippos fighting

Hippopotamuses are by nature very aggressive animals, especially when young calves are present. Frequent targets of their aggression include crocodiles, which often inhabit the same river habitat as hippos. Nile crocodiles, lions and spotted hyenas are known to prey on young hippos.[54] Hippos are very aggressive towards humansSony VAIO PCG-7148L battery, whom they commonly attack whether in boats or on land with no apparent provocation.[55] They are widely considered to be one of the most dangerous large animals in Africa.[56][57]

To mark territory, hippos spin their tails while defecating to distribute their excrement over a greater area.[58] Likely for the same reason, hippos are retromingent – that is, they urinate backwards. Sony VPCW21M2E/WI battery

When in combat, male hippos use their incisors to parry each others attacks, and their lower canines to inflict damage.[8] Hippos rarely kill each other, even in territorial challenges. Usually a territorial bull and a challenging bachelor will stop fighting when it is clear that one hippo is stronger. When hippos become overpopulatedSony VPCW21C7E battery, or when a habitat starts to shrink, bulls will sometimes attempt to kill infants, but this behavior is not common under normal conditions.[53] Some incidents of hippo cannibalism have been documented, but it is believed to be the behavior of distressed or sick hippos, and not healthy behavior.

Hippos and humans

A faience sculpture, from the New Kingdom of Egypt, 18th/19th dynasty, c. 1500–1300 BC, when hippos were still widespread along the NileSony VPCW12S1E/WZ battery

Obaysch lounging at the London Zoo in 1852

The earliest evidence of human interaction with hippos comes from butchery cut marks upon hippo bones at Bouri Formation dated around 160,000 years ago.[60] Later rock paintings and engravings showing hippos being hunted have been found in the mountains of the central Sahara dated 4,000–5,000 years ago near Djanet in the Tassili n'Ajjer MountainsSony VPCW12S1E/W battery. Hippos were also well-known to the ancient Egyptians, where the hippo was recognized as a ferocious denizen of the Nile.

The Hippopotamus was also known to the Greeks and Romans. The Greek historian Herodotus described the hippopotamus in The Histories (written circa 440 BC) and the Roman Historian Pliny the Elder wrote about the hippopotamus in his encyclopedia Naturalis Historia (written circa 77 AD). Sony VPCW12S1E/T batteryHippopotamus was one of the many exotic animals brought to fight gladiators in Rome by the emperor Philip I the Arab to commemorate Rome's 1000 years anniversary in 248 AD. Silver coins with hippo's image were minted that year.

Zulu warriors preferred to be as brave as a hippopotamus, since even lions were not considered as braveSony VPCW12S1E/P battery. "In 1888, Captain Baden-Powell was part of a column searching for the Zulu chief Dinizulu, who was leading the Usutu people in revolt against the British colonists. The column was joined by John Dunn, a white Zulu chief, who led an impi (army) of 2000 Zulu warriors to join the British." [62]

The words of the Zulu anthem sounded like this:

"Een-gonyama Gonyama! "Invooboo! Yah-bo! Yah-bo! Invooboo!" Sony VPCW11S1E/W battery

"John Dunn was at the head of his impi. [Baden Powell] asked him to translate the Zulu anthem his men had been singing. Dunn laughed and replied: "He is a lion. Yes, he is better than a lion—he is a hippopotamus." [63]

[edit]Hippos in zoos

Hippopotamuses have long been popular zoo animals. The first zoo hippo in modern history was Obaysch who arrived at the London Zoo on May 25, 1850, where he attracted up to 10,000 visitors a day and inspired a popular song, the Hippopotamus Polka. Sony VPCW11S1E/T battery Hippos have remained popular zoo animals since Obaysch, and generally breed well in captivity. Their birth rates are lower than in the wild, but this is attributed to zoos' not wanting to breed as many hippos as possible, since hippos are large and relatively expensive animals to maintain.

Like many zoo animals, hippos were traditionally displayed in concrete exhibits. In the case of hippos, they usually had a pool of water and patch of grassSony VPCW11S1E/P battery. In the 1980s, zoo designers increasingly designed exhibits that reflected the animals' native habitats. The best known of these, the Toledo Zoo Hippoquarium, features a 360,000 gallon pool for hippos.[65] In 1987, researchers were able to tape, for the first time, an underwater birth (as in the wild) at the Toledo Zoo. The exhibit was so popular that the hippos became the logo of the Toledo Zoo. Sony VPCYA1S1E/B battery

Cultural depictions

The cover of the Hippopotamus Polka. The unlikely portrayal of dancing hippos was echoed in Disney's Fantasia.

A red hippo represented the Ancient Egyptian god Set; the thigh is the 'phallic leg of set' symbolic of virility. Set's consort Tawaret was also seen as part hippo.[67] The hippopotamus-headed Tawaret was a goddess of protection in pregnancy and childbirthSony VPCYA1V9E/B battery, because ancient Egyptians recognized the protective nature of a female hippopotamus toward her young.[68] The Behemoth from the Book of Job, 40:15–24 is also thought to be based on a hippo.[69] The Ijo people wore masks of aquatic animals like the hippo when practicing their water spirit cults. Sony VPCY21S1E/SI battery

Hippos have been the subjects of various African folktales. According to a Bushmen story; when the Creator assigned each animal their place in nature, the hippos wanted to live in the water, but were refused out of fear that they might eat all the fish. After begging and pleading, the hippos were finally allowed to live in the water on the conditions that they would eat grass instead of fish and would fling their dung so he can inspect it for fish bones. Sony VPCY21S1E/L battery In a Ndebele tale, the hippo originally had long, beautiful hair but was set on fire by a jealous hare and had to jump into a nearby pool. The hippo lost most of his hair and was too embarrassed to leave the water.[71]

Ever since Obaysch inspired the Hippopotamus Polka, hippos have been popular animals in Western culture for their rotund appearance that many consider comical.[64] Stories of hippos like Huberta who became a celebrity in South Africa in the 1930s for trekking across the country; Sony VPCY21S1E/G battery or the tale of Owen and Mzee, a hippo and tortoise who developed an intimate bond; have amused people who have bought hippo books, merchandise, and many a stuffed hippo toy.[73][74] Hippos were mentioned in the novelty Christmas song "I Want a Hippopotamus for Christmas" that became a hit for child star Gayla Peevey in 1953. Sony VPCY11S1E/S batteryThey also feature in the songs "The Hippopotamus" and "Hippo Encore" by Flanders and Swann, with the famous refrain Mud, Mud, Glorious Mud. They even inspired a popular board game, Hungry Hungry Hippos.

Hippos have also been popular cartoon characters, where their rotund frame is used for humorous effect. The Disney film Fantasia featured a ballerina hippopotamus dancing to the opera, La Gioconda. Sony VPCY11S1E batteryOther cartoon hippos have included Hanna-Barbera's Peter Potamus, the book and TV series George and Martha, Flavio and Marita on the Animaniacs, Pat of the French duo Pat et Stanley, The Backyardigan's Tasha, and Gloria and Moto-Moto from the Madagascar franchise. A Sesame Street cartoon from the early 1970s features a hippo who lives in the country and likes it quiet, while being disturbed when the mouse who likes it loud moves in with herSony VPCZ11X9E/B battery.

The hippopotamus characters "Happy Hippos" were created in 1988 by the French designer Andre Roche [78] based in Munich, to be hidden in the "Kinder Surprise egg" of the Italian chocolate company Ferrero SpA. These characters were not placid like real hippos but rather cute and lively, and had such a success that they reappeared several times in different products of this company in the following years, increasing their popularity worldwide each timeSony VPCZ11Z9E/B battery. The Nintendo Company published in the years 2001 and 2007 Game Boy adventures of them. In the game of chess, the hippopotamus lends its name to the Hippopotamus Defense, an opening system, which is generally considered weak.The River Horse is a popular outdoor sculpture at George Washington University, Washington, D.CSony VPCZ12M9E/B battery.

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