Hippopotamus
Pod of hippos, Luangwa Valley, Zambia
Conservation status
Vulnerable (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Superorder: Cetartiodactyla Order: Artiodactyla Family: Hippopotamidae Genus: Hippopotamus Species: H. amphibius
Binomial name
Hippopotamus amphibius Linnaeus, 1758[2]
Range map[1]

The hippopotamus (Hippopotamus amphibius), from the Greek ἱπποπόταμος (hippopotamos, hippos meaning "horse" and potamos meaning "river"), often shortened to "hippo", is a large, mostly plant-eating African mammal, one of only two extant species in the family Hippopotamidae (the other being the Pygmy Hippopotamus). Image File history File links Download high-resolution version (2160x1440, 597 KB) Summary Pod of Hippos in Luangwa Valley, Zambia, 2002. ... Luangwa River, Zambia, southern end near Ndevu The Luangwa River is one of the major tributaries of the Zambezi River, and one of the four biggest rivers of Zambia. ... The conservation status of a species is an indicator of the likelihood of that species remaining extant either in the present day or the near future. ... Image File history File links Status_iucn3. ... This list is incomplete; you can help by expanding it. ... The IUCN Red List of Threatened Species (also known as the IUCN Red List and Red Data List), created in 1963, is the worlds most comprehensive inventory of the global conservation status of plant and animal species and can be found here. ... Scientific classification redirects here. ... For other uses, see Animal (disambiguation). ... Classes See below Chordates (phylum Chordata) are a group of animals that includes the vertebrates, together with several closely related invertebrates. ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... Orders Order: Cetacea Suborders: Suina Tylopoda Ruminantia Family: Hippopotamidae Humpback Whale breaching. ... Families Antilocapridae Bovidae Camelidae Cervidae Giraffidae Hippopotamidae Moschidae Suidae Tayassuidae Tragulidae Leptochoeridae † Chaeropotamidae † Dichobunidae † Cebochoeridae † Entelodontidae † Anoplotheriidae † Anthracotheriidae † Cainotheriidae † Agriochoeridae † Merycoidodontidae † Leptomerycidae † Protoceratidae † Xiphodontidae † Amphimerycidae † Helohyidae † Gelocidae † Merycodontidae † Dromomerycidae † Raoellidae † Choeropotamidae † Sanitheriidae † The even-toed ungulates form the mammal order Artiodactyla. ... Genera Hippopotamus Phanourios Hexaprotodon Archaeopotamus Choeropsis Saotherium Hippopotami (colloquially also Hippopotamuses) are the members of the family Hippopotamidae. ... Latin name redirects here. ... Carl Linnaeus, Latinized as Carolus Linnaeus, also known after his ennoblement as  , (May 13, 1707[1] – January 10, 1778), was a Swedish botanist, physician and zoologist[2] who laid the foundations for the modern scheme of nomenclature. ... Image File history File links Hippo_distribution. ... A deer and two fawns feeding on some foliage A herbivore is often defined as any organism that eats only plants[1]. By that definition, many fungi, some bacteria, many animals, about 1% of flowering plants and some protists can be considered herbivores. ... A world map showing the continent of Africa Africa is the worlds second-largest and second most-populous continent, after Asia. ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... For other uses, see Species (disambiguation). ... For other uses, see Scientific classification (disambiguation). ... Genera Hippopotamus Phanourios Hexaprotodon Archaeopotamus Choeropsis Saotherium Hippopotami (colloquially also Hippopotamuses) are the members of the family Hippopotamidae. ... Binomial name (Morton, 1849)[2] Range map[1] Subspecies C. l. ...

The hippopotamus is semi-aquatic, inhabiting rivers and lakes in sub-Saharan Africa in groups of 5-30 hippos. During the day they remain cool by staying in the water or mud; reproduction and childbirth both occur in water, where territorial bulls preside over a stretch of river. They emerge at dusk to graze on grass. While hippos rest near each other in territories in the water, grazing is a solitary activity and hippos are not territorial on land. Satellite image of Africa, showing the ecological break that defines the sub-Saharan area Sub-Saharan Africa is a geographical term used to describe the area of the African continent which lies south of the Sahara, or those African countries which are fully or partially located south of the Sahara. ...

Despite their physical resemblance to pigs and other terrestrial even-toed ungulates, their closest living relatives are cetaceans—whales, porpoises and the like. The common ancestor of whales and hippos split from other even-toed ungulates around 60 million years ago. The earliest known hippopotamus fossils, belonging to the genus Kenyapotamus in Africa, date to around 16 million years ago. For other uses, see Pig (disambiguation). ... Families Suidae Hippopotamidae Tayassuidae Camelidae Tragulidae Moschidae Cervidae Giraffidae Antilocapridae Bovidae The even-toed ungulates form the mammal order Artiodactyla. ... Suborders Mysticeti Odontoceti Archaeoceti (extinct) (see text for families) The order Cetacea (IPA: , L. cetus, whale) includes whales, dolphins and porpoises. ... This article is about the animal. ... Genera Neophocaena Phocoena - Harbor porpoise Phocoenoides - Dalls porpoise The porpoises are small cetaceans of the family Phocoenidae; they are related to whales and dolphins. ... Families Suidae Hippopotamidae Tayassuidae Camelidae Tragulidae Moschidae Cervidae Giraffidae Antilocapridae Bovidae The even-toed ungulates form the mammal order Artiodactyla. ... For other uses, see Genus (disambiguation). ... Binomial name Kenyapotamus coryndoni and Kenyapotamus ternani Pickford, 1983 Kenyapotamus is an extinct ancestor of the modern Hippopotamus which lived in Africa roughly 16 million to 8 million years ago during the Miocene epoch. ...

The hippopotamus is recognizable for its barrel-shaped torso, enormous mouth and teeth, hairless body, stubby legs and tremendous size. It is similar in size to the White Rhinoceros; only elephants are consistently heavier. Despite its stocky shape and short legs, it can easily outrun a human. Hippos have been clocked at 30 mph (48 km/h) while running short distances, faster than an Olympic sprinter. The hippopotamus is among the most dangerous and aggressive of all animals, and are regarded to be Africa's most dangerous animal. There are an estimated 125,000 to 150,000 hippos remaining throughout Sub-Saharan Africa, of which Zambia (40,000) and Tanzania (20,000-30,000) have the largest populations ^[1]. They are still threatened by poaching for their meat and ivory canine teeth, and by habitat loss. Binomial name Burchell, 1817 The White Rhinoceros original range (orange: Northern (C. s. ... Genera and Species Loxodonta Loxodonta cyclotis Loxodonta africana Elephas Elephas maximus Elephas antiquus † Elephas beyeri † Elephas celebensis † Elephas cypriotes † Elephas ekorensis † Elephas falconeri † Elephas iolensis † Elephas planifrons † Elephas platycephalus † Elephas recki † Stegodon † Mammuthus † Elephantidae (the elephants) is a family of pachyderm, and the only remaining family in the order Proboscidea...

Taxonomy and origins

Hippopotamuses (plural hippopotami is also used ^[3] ; hippos can be used as a short plural) are gregarious, living in groups of up to 40 animals; such a group is called a pod, herd, dale, or bloat. A male hippopotamus is known as a bull, a female as a cow, and a baby as a calf. They are also known as the Common Hippopotamus or the Nile Hippopotamus. This article needs additional references or sources for verification. ...

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 Hippopotamoidea. In biology, a type is that which fixes a name to a taxon. ... Genera Hippopotamus Phanourios Hexaprotodon Archaeopotamus Choeropsis Saotherium Hippopotami (colloquially also Hippopotamuses) are the members of the family Hippopotamidae. ... Binomial name (Morton, 1849)[2] Range map[1] Subspecies C. l. ... Binomial name Hexaprotodon liberiensis (Morton, 1849) The Pygmy Hippopotamus (Hexaprotodon liberiensis) is a large mammal native to the forests and swamps of western Africa (the species name, meaning of Liberia, reflects this). ... Binomial name Choeropsis liberiensis (Morton, 1849) Subspecies The Pygmy Hippopotamus (Choeropsis liberiensis) is a large mammal native to the forests and swamps of western Africa (the species name, meaning of Liberia, reflects this). ... Anthracotheriidae is a family of extinct, hippopotamus-like artiodactyl ungulates related to both hippopotami and pigs. ...

Five subspecies of hippos have been described based on morphological differences in their skulls and geographical differences:^[4] The term morphology in biology refers to the outward appearance (shape, structure, colour, pattern) of an organism or taxon and its component parts. ...

• H. a. amphibius – (the nominate subspecies) which stretched from Egypt, where they are now extinct down the Nile River to Tanzania and Mozambique.
• H. a. kiboko – in the Horn of Africa, in Kenya and Somalia. Kiboko is the Swahili word for hippo. 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 orbits.
• 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.^[5] Genetic 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.constrictus nor H.a.tschadensis have been tested.^[6][7] There is also Nile, a death metal band from South Carolina, USA. The Nile in Egypt Length 6 695 km Elevation of the source 1 134 m Average discharge 2 830 m³/s Area watershed 3 400 000 km² Origin Africa Mouth the Mediterranean Basin countries Uganda - Sudan - Egypt The... The Horn of Africa. ... The Democratic Republic of the Congo, called Zaïre between 1971 and 1997, is a nation in central Africa. ... Mitochondrial DNA (some captions in German) Mitochondrial DNA (mtDNA) is the DNA located in organelles called mitochondria. ...

Classification

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

Hippopotamidae are classified along with other even-toed ungulates in the order, Artiodactyla. Other members of Artiodactyla include camels, cows, deer and pigs; although hippopotamuses are not closely related to these species. Image File history File links Download high resolution version (2016x1512, 960 KB) A hippos skull. ... Image File history File links Download high resolution version (2016x1512, 960 KB) A hippos skull. ... For other uses of Skull, see Skull (disambiguation). ... The Canine teeth are the long, pointed teeth used for grabbing hold of and tearing apart foods, also called cuspids, dogteeth or fangs. Species that feature them, such as humans and dogs, usually have four, two in the top jaw, two in the lower, on either side of the Incisors. ... Families Suidae Hippopotamidae Tayassuidae Camelidae Tragulidae Moschidae Cervidae Giraffidae Antilocapridae Bovidae The even-toed ungulates form the mammal order Artiodactyla. ... In scientific classification used in biology, the order (Latin: ordo, plural ordines) is a rank between class and family (termed a taxon at that rank). ... Families Suidae Hippopotamidae Tayassuidae Camelidae Tragulidae Moschidae Cervidae Giraffidae Antilocapridae Bovidae The even-toed ungulates form the mammal order Artiodactyla. ... For other uses, see Camel (disambiguation). ... Binomial name Bos taurus Linnaeus, 1758 Rainbow arching over a paddock of cattle Cattle are domesticated ungulates, a member of the subfamily Bovinae of the family Bovidae. ... This article is about the ruminant animal. ... This article needs additional references or sources to facilitate its verification. ...

As indicated by the name, ancient Greeks considered the hippopotamus to be related to the horse. Until 1985, naturalists grouped hippos with pigs, based on molar patterns. Evidence, first from blood proteins, then from molecular systematics^[8] and DNA ^[9] and the fossil record, show that their closest living relatives are cetaceans—whales, porpoises and the like.^[10][11] Hippopotamuses have more in common with whales than they do with other Artiodactyls (even-toed ungulates), such as pigs, because the common ancestor of hippos and whales branched-off from ruminants and the rest of the even-toed ungulates. Thus, hippos are more closely related to whales than to other members of Artiodactyla. While cetaceans and hippos are each other's closest living relatives, their lineages split soon after their divergence from the rest of the even-toed ungulates.^[12][9] Table of natural history, 1728 Cyclopaedia Natural history is an umbrella term for what are now often viewed as several distinct scientific disciplines of integrative organismal biology. ... For other uses, see Pig (disambiguation). ... Molars are the rearmost and most complicated kind of tooth in most mammals. ... For other uses, see Blood (disambiguation). ... A representation of the 3D structure of myoglobin showing coloured alpha helices. ... It has been suggested that molecular phylogeny be merged into this article or section. ... The structure of part of a DNA double helix Deoxyribonucleic acid, or DNA, is a nucleic acid molecule that contains the genetic instructions used in the development and functioning of all known living organisms. ... It has been suggested that this article or section be merged into Fossil. ... Suborders Mysticeti Odontoceti (see text) The order Cetacea includes whales, dolphins and porpoises. ... This article is about the animal. ... Genera Neophocaena Phocoena - Harbor porpoise Phocoenoides - Dalls porpoise The porpoises are small cetaceans of the family Phocoenidae; they are related to whales and dolphins. ... Families Antilocapridae Bovidae Camelidae Cervidae Giraffidae Hippopotamidae Moschidae Suidae Tayassuidae Tragulidae Leptochoeridae † Chaeropotamidae † Dichobunidae † Cebochoeridae † Entelodontidae † Anoplotheriidae † Anthracotheriidae † Cainotheriidae † Agriochoeridae † Merycoidodontidae † Leptomerycidae † Protoceratidae † Xiphodontidae † Amphimerycidae † Helohyidae † Gelocidae † Merycodontidae † Dromomerycidae † Raoellidae † Choeropotamidae † Sanitheriidae † The even-toed ungulates form the mammal order Artiodactyla. ... Ungulates (meaning roughly hoofed or hoofed animal) make up several orders of mammals, of which six survive: Artiodactyla: even-toed ungulates, cattle, sheep, goats, pigs, antelope, and many others Cetacea: whales and dolphins (which evolved from hoofed land animals) Perissodactyla: odd-toed ungulates such as horses and rhinos Proboscidea: elephants... It has been suggested that this article or section be merged with Ruminantia. ...

Evolution

The most recent theory into 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.^[10][9] This hypothesized ancestor likely split into two branches around 54 million years ago.^[8] One branch would evolve into cetaceans, possibly beginning with the proto-whale Pakicetus from 52 million years ago and other early whale ancestors, known as Archaeoceti, which eventually underwent aquatic adaptation into the almost completely aquatic cetaceans.^[12] The cetaceans (whales, dolphins and porpoises) are descendants of land-living mammals, and remnants of their terrestrial origins can be found in the fact that they must breathe air from the surface; in the bones of their fins, which look like huge, jointed hands; and in the vertical movement of... Binomial name Pakicetus inachus Gingerich & Russell, 1981 Pakicetus is a genus of extinct cetaceans found in the upper Eocene of Pakistan, whence their name. ... Families and Clades see text Archaeoceti, or ancient whales are a paraphyletic group of cetaceans that gave rise to Autoceti - the new cetaceans. ... This article needs cleanup. ... Suborders Mysticeti Odontoceti Archaeoceti (extinct) (see text for families) The order Cetacea (IPA: , L. cetus, whale) includes whales, dolphins and porpoises. ...

Anthracotherium magnus and Elomeryx armatus, two anthracotheres from the Oligocene, already bore similarities to the modern hippopotamus.

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 without leaving any descendants.^[10] Image File history File links Metadata Size of this preview: 794 × 600 pixelsFull resolution (900 × 680 pixel, file size: 761 KB, MIME type: image/jpeg) My reconstruction of the anthracothere Anthracotherium magnus, of early Oligocene France. ... Image File history File links Metadata Size of this preview: 794 × 600 pixelsFull resolution (900 × 680 pixel, file size: 761 KB, MIME type: image/jpeg) My reconstruction of the anthracothere Anthracotherium magnus, of early Oligocene France. ... -1... Species Elomeryx is an extinct genus of mammal. ... Anthracotheriidae is a family of extinct, hippopotamus-like artiodactyl ungulates related to both hippopotami and pigs. ... The Oligocene epoch is a geologic period of time that extends from about 34 million to 23 million years before the present. ... Anthracotheriidae is a family of extinct, hippopotamus-like artiodactyl ungulates related to both hippopotami and pigs. ... hfajhfiudshfas == == == --24. ... Genera Hippopotamus Phanourios Hexaprotodon Archaeopotamus Choeropsis Saotherium Hippopotami (colloquially also Hippopotamuses) are the members of the family Hippopotamidae. ...

A rough evolution can be traced, however, from Eocene and Oligocene species: Anthracotherium and Elomeryx to the Miocene anthracotheres Merycopotamus and Libycosaurus. Merycopotamus, Libycosaurus and all hippopotamids can be considered to form a clade, with Libycosaurus being more closely related to hippos. Their common ancestor would have lived in the Miocene, about 20 million years ago. The last species of anthracotheres became extinct during the pliocene.^[13] The Oligocene epoch is a geologic period of time that extends from about 34 million to 23 million years before the present. ... -1... Species Elomeryx is an extinct genus of mammal. ... The Miocene Epoch is a period of time that extends from about 23. ... Merycopotamus is an extinct species of Anthracothere that existed in the Middle Miocene. ... This Tree of Life article needs to be cleaned up to conform to a higher standard of quality. ... A clade is a term belonging to the discipline of cladistics. ... The Pliocene epoch (spelled Pleiocene in some older texts) is the period in the geologic timescale that extends from 5. ...

Hippopotamids are therefore deeply nested within the family Anthracotheriidae. The oldest known hippopotamid is the genus Kenyapotamus which lived in Africa from 16 to 8 million years ago. The Hippopotamidae are believed to have evolved in Africa, and while at one point species spread across Asia and Europe, no hippopotamuses have ever been discovered in the Americas, though, 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, the Archaeopotamus lived in Africa and the Middle East.^[14] Anthracotheriidae is a family of extinct, hippopotamus-like artiodactyl ungulates related to both hippopotami and pigs. ... Binomial name Kenyapotamus coryndoni and Kenyapotamus ternani Pickford, 1983 Kenyapotamus is an extinct ancestor of the modern Hippopotamus which lived in Africa roughly 16 million to 8 million years ago during the Miocene epoch. ... The Oligocene epoch is a geologic period of time that extends from about 34 million to 23 million years before the present. ... Species Archaeopotamus is an extinct genus of hippopotamidae that lived between 7. ...

While the fossil record of hippos is still poorly understood, the two modern genera, Hippopotamus and Choeropsis (sometimes Hexaprotodon), may have diverged as far back as 8 million years ago. Scientists disagree whether or not the modern Pygmy Hippopotamus is a member of Hexaprotodon—a genus of many Asian Hippopotamuses that is more-closely related to Hippopotamus; or Choeropsis—an older and basal genus.^[14][13] Binomial name Hexaprotodon liberiensis (Morton, 1849) The Pygmy Hippopotamus (Hexaprotodon liberiensis) is a large mammal native to the forests and swamps of western Africa (the species name, meaning of Liberia, reflects this). ... Binomial name Choeropsis liberiensis (Morton, 1849) Subspecies The Pygmy Hippopotamus (Choeropsis liberiensis) is a large mammal native to the forests and swamps of western Africa (the species name, meaning of Liberia, reflects this). ... Binomial name (Morton, 1849)[2] Range map[1] Subspecies C. l. ... In phylogenetics, basal members of a group diverged earlier than a subgroup of others (or vice versa). ...

Extinct species

Hippopotamus gorgops, which had unusually high orbits, lived in Europe but became extinct before the last Ice Age.

As many as 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.^[15] There is fossil evidence that many Malagasy Hippos were hunted by humans, a likely factor in their eventual extinction.^[16][15] 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.^[17] This article or section does not cite its references or sources. ... Species Hippopotamus lemerlei [1] Hippopotamus laloumena[2] [1] or [3] or [4] Several species of Malagasy Hippopotamus (also known as Malagasy Dwarf Hippopotamus or Malagasy Pygmy Hippopotamus or Madagascan instead of Malagasy) lived on the island of Madagascar but are now believed to be extinct. ... The Holocene epoch is a geological period, which began approximately 11,550 calendar years BP (about 9600 BC) and continues to the present. ... Insular dwarfism is the process and condition of the reduction in size of large animals - almost always mammals - when their gene pool is limited to a very small environment, primarily islands. ...

A separate 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 glaciation. Ancestors of European Hippos, found their way to many islands of the Mediterranean, during the Pleistocene.^[18] Binomial name Hippopotamus antiquus Desmarest 1822 The European Hippopotamus (Hippopotamus antiquus) was a species of hippopotamus that ranged across Europe, becoming extinct some time before the last ice age at the end of the Pleistocene epoch. ... This article or section does not cite its references or sources. ... The Mediterranean Sea is an intercontinental sea positioned between Europe to the north, Africa to the south and Asia to the east, covering an approximate area of 2. ... The Pleistocene epoch (IPA: ) on the geologic timescale is the period from 1,808,000 to 11,550 years BP. The Pleistocene epoch had been intended to cover the worlds recent period of repeated glaciations. ...

These Pleistocene dwarf hippos of the Mediterranean lived on Crete (H. creutzburgi), Cyprus (H. minor), Malta (H. melitensis) and Sicily (H. pentlandi). Of these, the Cyprus Dwarf Hippopotamus, 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 encountered, and was driven to extinction, by man.^[19][18] Binomial name Hippopotamus creutzburgi Boekschoten and Sondaar, 1966[1] The Cretan Dwarf Hippopotamus or Hippopotamus creutzburgi is an extinct hippopotamus. ... Binomial name Hippopotamus pentlandi Von Meyer, 1832[1] Hippopotamus pentlandi is an extinct hippopotamus. ... Binomial name Phanourios minutus The Cyprus Dwarf Hippopotamus or Cypriot Pygmy Hippopotamus (Phanourios minutus) is an extinct species of hippo that inhabited the island of Cyprus until the early Holocene. ... The Pleistocene epoch (IPA: ) on the geologic timescale is the period from 1,808,000 to 11,550 years BP. The Pleistocene epoch had been intended to cover the worlds recent period of repeated glaciations. ... Aetokremnos is a rock shelter near Limassol on the southern coast of Cyprus. ...

Description

The head of a hippo at the zoo in Lisbon.

Hippopotamuses are one of the largest extant mammals in the world. Hippos are considered megafauna, but unlike all other African megafauna, hippos have adapted for a semi-aquatic life in freshwater lakes and rivers.^[5] Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (3264 × 2448 pixel, file size: 2. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (3264 × 2448 pixel, file size: 2. ... For other uses, see Lisbon (disambiguation). ... It has been suggested that Charismatic megafauna be merged into this article or section. ... For other uses, see Adaptation (disambiguation). ...

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 1960s. The average weights for adult males ranged between 1500–1800 kg (3,300–4,000 lbs). Females are smaller than their male counterparts, with average weights measuring between 1300–1,500 kg (2,900–3,300 lbs).^[5] Older males can get much larger, reaching at least 3,200 kg (7,100 lbs) and occasionally weighing 3636 kg (8000 lbs)^[20]. Male hippos appear to continue growing throughout their lives; females reach a maximum weight at around age 25.^[21] To cull is to remove from a group of animals those individuals who show signs of weakness. ...

On the National Geographic Channel television program, "Dangerous Encounters with Brady Barr", Dr. Brady Barr measured the bite of an adult female hippo at 1,821 lb (826 kg). after abandoning an attempt to measure the bite of an adult male due to its aggressiveness.^[22] The National Geographic Channel is a subscription television network that features documentaries produced by the National Geographic Society. ... Brady Barr is the host of National Geographics Reptile Wild and Dangerous Encounters. ...

Hippos average 3.5 meters (11 ft) long, 1.5 meters (5 ft) tall at the shoulder. 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 elephants. 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.^[5] Binomial name Burchell, 1817 The White Rhinoceros original range (orange: Northern (C. s. ... Genera and Species Loxodonta Loxodonta cyclotis Loxodonta africana Elephas Elephas maximus Elephas antiquus † Elephas beyeri † Elephas celebensis † Elephas cypriotes † Elephas ekorensis † Elephas falconeri † Elephas iolensis † Elephas planifrons † Elephas platycephalus † Elephas recki † Stegodon † Mammuthus † Elephantidae (the elephants) is a family of pachyderm, and the only remaining family in the order Proboscidea...

A bull hippo out of water during daylight, Ngorongoro Crater, Tanzania.

A hippo's lifespan is typically 40 to 50 years.^[5] Donna the Hippo, 56, is the oldest living hippo in captivity. She lives at the Mesker Park Zoo in Evansville, Indiana.^[23][24] The oldest hippo ever was called Tanga; she lived in Munich, Germany, and died in 1995 at the age of 61.^[25] Image File history File links Metadata Size of this preview: 800 × 490 pixelsFull resolution (2586 × 1584 pixel, file size: 136 KB, MIME type: image/jpeg) Hippopotomus out of water, Ngorongoro Crater, Tanzania. ... Image File history File links Metadata Size of this preview: 800 × 490 pixelsFull resolution (2586 × 1584 pixel, file size: 136 KB, MIME type: image/jpeg) Hippopotomus out of water, Ngorongoro Crater, Tanzania. ... Mesker Park Zoo The Mesker Park Zoo and Botanic Garden is a zoo located in Evansville, Indiana. ... For other places named Evansville, see Evansville (disambiguation). ...

A drawing of a hippopotamus skeleton.

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 general anatomical structure is an adaptation to their riparian lifestyle. Their skeletal structure is graviportal, adapted to carrying the animals' enormous weight. Hippopotamuses have legs that are small, relative to other megafauna, because the water in which they live reduces the weight burden. Like other aquatic mammals, the hippopotamus has very little hair.^[5] Image File history File links Size of this preview: 800 × 371 pixelsFull resolution (936 × 434 pixel, file size: 176 KB, MIME type: image/png) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Hippopotamus ... Image File history File links Size of this preview: 800 × 371 pixelsFull resolution (936 × 434 pixel, file size: 176 KB, MIME type: image/png) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Hippopotamus ... A noontime scene from the Philippines on a day when the Sun is almost directly overhead. ... For other uses, see Adaptation (disambiguation). ... A riparian zone schematic from the Everglades. ... It has been suggested that Charismatic megafauna be merged into this article or section. ...

Eye of a hippo in San Francisco Zoo

For additional protection from the sun, 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 and one orange. The two pigments are highly acidic compounds. They are known as red pigment hipposudoric acid and orange pigment norhipposudoric acid. The red pigment was found to inhibit the growth of disease-causing bacteria, lending credence to the theory that the secretion has an antibiotic effect. 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. ^[26] Image File history File links Size of this preview: 800 × 533 pixelsFull resolution (1728 × 1152 pixels, file size: 1. ... Image File history File links Size of this preview: 800 × 533 pixelsFull resolution (1728 × 1152 pixels, file size: 1. ... Sunscreen (also known as sunblock, suntan lotion) is a lotion, spray or other topical product that is intended to protect the skin from the suns ultraviolet (UV) radiation. ... Natural Ultramarine pigment in powdered form. ... For other uses, see acid (disambiguation). ... Phyla Actinobacteria Aquificae Chlamydiae Bacteroidetes/Chlorobi Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Lentisphaerae Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Verrucomicrobia Bacteria (singular: bacterium) are unicellular microorganisms. ... Staphylococcus aureus - Antibiotics test plate. ... Absorption, in optics, is the process by which the energy of a photon is taken up by another entity, for example, by an atom whose valence electrons make a transition between two electronic energy levels. ... For other uses, see Ultraviolet (disambiguation). ... A protein precursor is an inactive protein (or peptide) that can be turned into an active form by posttranslational modification. ... This article is about the class of chemicals. ... Tyrosine (from the Greek tyros, meaning cheese, as it was first discovered in 1846 by German chemist Justus von Liebig in the protein casein from cheese[1][2]), 4-hydroxyphenylalanine, or 2-amino-3(4-hydroxyphenyl)-propanoic acid, is one of the 20 amino acids that are used by cells...

Distribution

Hippopotamus amphibius was widespread in North Africa and Europe before the last glaciation event, and it can live in colder climates provided the water does not freeze during winter. 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;^[27] 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, northern 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 Mozambique.^[5]  Northern Africa (UN subregion)  geographic, including above North Africa or Northern Africa is the northernmost region of the African continent, separated by the Sahara from Sub-Saharan Africa. ... For other uses, see Europe (disambiguation). ... A glaciation (a created composite term meaning Glacial Period, referring to the Period or Era of, as well as the process of High Glacial Activity), often called an ice age, is a geological phenomenon in which massive ice sheets form in the Arctic and Antarctic and advance toward the equator. ... For other uses, see Nile (disambiguation). ... Pliny the Elder: an imaginative 19th Century portrait. ... Sais was the chief city of the fifth nome of Lower Egypt, located in the western edge of the Nile Delta. ... The Republic of The Gambia is a country in West Africa. ... Categories: Africa geography stubs | Southern Africa ... The Republic of South Africa is a large republic located at the southern tip of the continent. ...

Conservation status

The Hippopotamus Hunt (1617), by Peter Paul Rubens.

Evidence through genetic analysis 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.^[6] Hippos are also subject to unregulated or illegal poaching. In addition to addressing these common threats, the genetic diversity of hippos would need to be preserved to ensure the safety of the species. 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 percent and 20 percent since the IUCN's 1996 study.^[1] Image File history File links Download high resolution version (3176x2486, 796 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Hippopotamus Peter Paul Rubens User:Rl/Images ... Image File history File links Download high resolution version (3176x2486, 796 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Hippopotamus Peter Paul Rubens User:Rl/Images ... Peter Paul Rubens (June 28, 1577 – May 30, 1640) was a prolific seventeenth-century Flemish and European painter, and a proponent of an exuberant Baroque style that emphasized movement, color, and sensuality. ... The Pleistocene epoch is part of the geologic timescale, usually dated as 1. ... For other uses, see Poaching (disambiguation). ... This list is incomplete; you can help by expanding it. ... The IUCN Red List of Threatened Species (also known as the IUCN Red List and Red Data List), created in 1963, is the worlds most comprehensive inventory of the global conservation status of plant and animal species and can be found here. ... The World Conservation Union or International Union for the Conservation of Nature and Natural Resources (IUCN) is an international organization dedicated to natural resource conservation. ...

The hippo population declined most dramatically in the Democratic Republic of the Congo.^[28] The population in Virunga National Park had dropped to 800 or 900 individuals from around 29,000 in the mid 1970s, raising concerns about the viability of that population.^[29] The decline is attributed to the disruptions caused by the Second Congo War.^[29] Poachers are believed to be former Hutu rebels, poorly paid Congolese soldiers, and local militia groups.^[29] Reasons for poaching include the belief that hippos are unintelligent, that they are a harm to society, and also for money.^[30] The sale of hippo meat is illegal, but black-market sales are difficult for WWF officers to track.^[29][30] The Virunga National Park lies in the Virunga Mountains of the eastern Democratic Republic of Congo, bordering Volcans National Park in Rwanda and Rwenzori National Park in Uganda. ... Combatants Democratic Republic of the Congo, Namibia, Zimbabwe, Angola, Chad, Mai-Mai, Hutu-aligned forces Uganda, Rwanda, Burundi, Movement for the Liberation of Congo Congolese Rally for Democracy Tutsi-aligned forces Commanders Laurent-Désiré Kabila (Congo), Joseph Kabila (Congo), Sam Nujoma Robert Mugabe José Eduardo dos Santos Idriss D... The Hutu are a Central African ethnic group, living mainly in Rwanda and Burundi. ... The World Wide Fund for Nature (WWF) is an international non-governmental organization for the conservation, research and restoration of the natural environment, formerly named the World Wildlife Fund, which remains its official name in the United States and Canada. ...

Invasive potential

In Colombia, Pablo Escobar maintained four hippos in a private menagerie at his residence in Hacienda Napoles, 100 km east of Medellín, after purchasing them in New Orleans. They were deemed too difficult to seize and move after the fall of Escobar, and hence left on the untended estate. By 2007, the animals had multiplied to 16 individuals and taken to roaming the area for food. Considered too difficult to move by local authorities, their fate remains uncertain as their presence is impeding development of the site.^[31] Pablo Emilio Escobar Gaviria, a. ... (Spanish for Naples State) was the luxurious estate built and owned by Colombian drug dealer Pablo Escobar in Puerto Triunfo, Antioquia (320 kms NW from Bogotá) with about 2000 ha. ... For other uses, see Medellín (disambiguation). ...

Behavior

An open mouth signals that the Hippo feels threatened.

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 cool, and to keep their skin from drying out. With the exception of eating, most of hippopotamuses' lives—from childbirth, fighting with other hippos, and reproduction—occur in the water. Image File history File links Download high resolution version (807x591, 281 KB) Summary Subject: Hippopotamus Photographer: User:Nv8200p Date: Mid 1980s Location: San Antonio Zoo, San Antonio, Texas Licensing File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Download high resolution version (807x591, 281 KB) Summary Subject: Hippopotamus Photographer: User:Nv8200p Date: Mid 1980s Location: San Antonio Zoo, San Antonio, Texas Licensing File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

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.^[32] Like almost any herbivore, they will consume many other plants if presented with them, but their diet in nature consists almost entirely of grass, with only minimal consumption of aquatic plants.^[33] Hippos have (rarely) been filmed eating carrion, usually close to the water. There are other reports of meat-eating, and even cannibalism and predation.^[34] The stomach anatomy of a hippo is not suited to carnivory, and meat-eating is likely caused by aberrant behavior or nutritional stress.^[5] An American Black Vulture feeding on squirrel carrion For other uses, see Carrion (disambiguation). ... Cannibal redirects here. ... Predator and Prey redirect here. ...

The diet of hippos consists mostly of terrestrial grasses, but 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.^[33] Because of their size and their habit of taking the same paths to feed, 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.^[35] Schematic overview of a thrust system. ...

A submerged hippo at the San Diego Zoo. Adult hippos typically resurface to breathe every 3–5 minutes.

Interestingly, adult hippos can't actually swim and are not generally buoyant. When in deep water, they usually propel themselves by leaps, pushing off from the bottom. They move at speeds up to 8 km/h (5 mph) in water. However, young hippos are buoyant and more often move by swimming—propelling themselves with kicks of their back legs. Adult hippos typically resurface to breathe every 4–6 minutes. The young have to breathe every two to three minutes.^[5] 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. Wikipedia does not have an article with this exact name. ... Wikipedia does not have an article with this exact name. ... The world-famous San Diego Zoo in Balboa Park, San Diego, California is one of the largest, most progressive zoos in the world with over 4,000 animals of more than 800 species. ... In physics, buoyancy is an upward force on an object immersed in a fluid (i. ...

Social life

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.^[36] Although hippos like to lie in close proximity to each other, they do not seem to form social bonds except between mothers and daughters, and are not social animals. The reason they huddle in close proximity is unknown.^[5] Female (left) and male Common Pheasant, illustrating the dramatic difference in form between the sexes Sexual dimorphism is the systematic difference in form between individuals of different sex in the same species. ...

It is difficult to identify the gender of hippos in the field, because all researchers can usually see are their backs, like with this pod in Tanzania.

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 up to 100 hippos. Other bachelors are allowed in a bull's stretch, 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.^[5] Image File history File links Size of this preview: 800 × 533 pixelsFull resolution (3250 × 2167 pixel, file size: 1. ... Image File history File links Size of this preview: 800 × 533 pixelsFull resolution (3250 × 2167 pixel, file size: 1. ...

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.^[37]

Reproduction

Female hippos reach sexual maturity at 5 to 6 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.^[38] Males reach maturity at around 7.5 years. This article does not cite any references or sources. ... The endocrine system is an integrated system of small organs that involve the release of extracellular signaling molecules known as hormones. ...

A study of hippopotamus reproductive behavior in Uganda showed that peak conceptions occurred during the end of the wet season in the summer, and peak births occurred toward the beginning of the wet season in late winter. This is because of the female's oestrous 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.^[5] After becoming pregnant, a female hippopotamus will typically not begin ovulation again for 17 months.^[38] Estrus (also spelled œstrus) or heat in female mammals is the period of greatest female sexual responsiveness usually coinciding with ovulation. ... Schematic diagram of a sperm cell, showing the (1) acrosome, (2) cell membrane, (3) nucleus, (4) mitochondria, and (5) flagellum (tail) A sperm cell, or spermatozoon ( spermatozoa) (in Greek: sperm = semen and zoon = alive), is the haploid cell that is the male gamete. ...

Hippos can be rather dangerous to humans, as this sign from Kruger National Park notes.

Mating occurs in the water with the female submerged for most of the encounter, 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 breath. A mother typically gives birth to only one hippo, although twins occur at an unknown ratio. 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.^[5] Image File history File links Size of this preview: 359 × 599 pixelsFull resolution (471 × 786 pixel, file size: 320 KB, MIME type: image/jpeg) (All user names refer to commons. ... Image File history File links Size of this preview: 359 × 599 pixelsFull resolution (471 × 786 pixel, file size: 320 KB, MIME type: image/jpeg) (All user names refer to commons. ... Kruger National Park is the largest game reserve in South Africa. ... Families Dugongidae Trichechidae Hydrochichus (extinct) For information about the Gothic metal band, see Sirenia (band) The Sirenia are fully aquatic, herbivorous mammals that inhabit rivers, estuaries and coastal marine waters. ... For other uses, see Manatee (disambiguation). ... Binomial name (Müller, 1776) Natural range of . ... A breastfeeding infant Breastfeeding is the practice of a woman feeding an infant (or sometimes a toddler or a young child) with milk produced from her mammary glands, usually directly from the nipples. ...

Hippos are considered K-strategists, meaning that they favor quality over quantity in their reproduction. K-selection is the norm for large animals that produce few young at each birth.^[5][39] In ecology, K-selection (note : upper case K) relates to the selection of traits (in organisms) that allow success in stable or predictable environments. ...

Aggression

Hippopotami are very violent tempered animals. Adult hippos are hostile toward crocodiles, which often live in the same pools and rivers as hippos. This is especially so when hippo calves are around. Hippos have been known to be very aggressive towards humans, and it is often claimed that hippos are the deadliest animal in Africa; however, according to Smithsonian Magazine, while the animal is very dangerous, reliable statistics for this are unavailable.^[28] For other uses, see Crocodile (disambiguation). ... Smithsonian is a monthly magazine published by the Smithsonian Institution of the United States in Washington, DC External link Smithsonian webpage Categories: Smithsonian Institution | United States magazines | Stub ...

To mark territory, hippos spin their tails while defecating to distribute their excrement over the greatest possible