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The hippopotamus ( ; ''Hippopotamus amphibius''), also called the hippo, common hippopotamus or river hippopotamus, is a large, mostly
herbivorous A herbivore is an animal Animals (also called Metazoa) are multicellular A multicellular organism is an organism In biology, an organism () is any organic, life, living system that functions as an individual entity. All ...
, semiaquatic mammal and
ungulate Ungulates ( ) are members of the diverse clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyly, monophyletic – that is, composed of a common ancestor and all its lineage (evoluti ...
native to
sub-Saharan Africa Sub-Saharan Africa (commonly called Black Africa) is, geographically, the area of the continent of Africa that lies south of the Sahara. According to the United Nations, it consists of all list of sovereign states and dependent territories i ...

sub-Saharan Africa
. It is one of only two
extant Extant is the opposite of the word extinct Extinction is the termination of a kind of organism In biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Bio ...
species In biology, a species is the basic unit of biological classification, classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individu ...

species
in the
family In human society A society is a Social group, group of individuals involved in persistent Social relation, social interaction, or a large social group sharing the same spatial or social territory, typically subject to the same Politic ...

family
Hippopotamidae :''This is the article on the family Hippopotamidae; for the main article on hippos, see Hippopotamus The hippopotamus ( ; ''Hippopotamus amphibius''), also called the hippo, common hippopotamus or river hippopotamus, is a large, mostly her ...

Hippopotamidae
, the other being the
pygmy hippopotamus The pygmy hippopotamus (''Choeropsis liberiensis'') is a small hippopotamid which is native to the forests and swamps of West Africa West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa ...

pygmy hippopotamus
(''Choeropsis liberiensis'' or ''Hexaprotodon liberiensis''). The name comes from the
ancient Greek Ancient Greek includes the forms of the Greek language Greek ( el, label=Modern Greek Modern Greek (, , or , ''Kiní Neoellinikí Glóssa''), generally referred to by speakers simply as Greek (, ), refers collectively to the diale ...
for "river horse" (). After the
elephant Elephants are the largest existing land animals. Three living species In biology, a species is the basic unit of biological classification, classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A specie ...

elephant
and
rhinoceros A rhinoceros (, , ), commonly abbreviated to rhino, is a member of any of the five extant Extant is the opposite of the word extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. T ...

rhinoceros
, the hippopotamus is the third- largest type of land mammal and is the heaviest extant
artiodactyl The even-toed ungulates (Artiodactyla , ) are ungulate Ungulates ( ) are members of the diverse clade A clade (; from grc, , ''klados'', "branch"), also known as a monophyletic group or natural group, is a group of organisms that are mo ...
(in the traditional, non-cladistic sense of the term, excluding cetaceans). Despite their physical resemblance to
pig The pig (''Sus domesticus''), often called swine, hog, or domestic pig when distinguishing from other members of the genus '' Sus'', is an omnivorous An omnivore () is an animal that has the ability to eat and survive on both plant and ani ...

pig
s and other terrestrial even-toed
ungulate Ungulates ( ) are members of the diverse clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyly, monophyletic – that is, composed of a common ancestor and all its lineage (evoluti ...
s, the closest living relatives of the Hippopotamidae are
cetacea Cetaceans (from la, cetus Cetus () is a constellation, sometimes called 'the whale' in English. The Cetus (mythology), Cetus was a sea monster in Greek mythology which both Perseus and Heracles needed to slay. Cetus is in the region of the ...

cetacea
ns (
whale Whales are a widely distributed and diverse group of fully aquatic Aquatic means relating to water Water (chemical formula H2O) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is ...

whale
s,
dolphin Dolphin is the common name of aquatic mammal Aquatic and semiaquatic mammals are a diverse group of mammal Mammals (from Latin language, Latin , 'breast') are a group of vertebrate animals constituting the class (biology), class Mam ...

dolphin
s,
porpoise Porpoises are a group of fully aquatic marine mammals, similar in appearance to a dolphin Dolphin is the common name of aquatic mammal Aquatic and semiaquatic mammals are a diverse group of mammal Mammals (from Latin language, ...

porpoise
s, etc.), from which they diverged about 55 million years ago. Hippos are recognisable by their barrel-shaped torsos, wide-opening mouths revealing large
canine Canine may refer to: Zoology * dog-like mammals (i.e. members of the canid subfamily Caninae) ** ''Canis'', a genus including dogs, wolves, coyotes, and jackals ** Dog, the domestic dog * Canine tooth, in mammalian oral anatomy Other uses * Canin ...
tusks, nearly hairless bodies, columnar legs and large size; adults average for males and for females. Despite its stocky shape and short legs, it is capable of running over short distances. Hippos inhabit rivers, lakes, and
mangrove A mangrove is a shrub A shrub (often called a bush) is a small- to medium-sized perennial A perennial plant or simply perennial is a plant Plants are predominantly photosynthetic eukaryotes of the Kingdom (biology), kingdom Pl ...

mangrove
swamps, where territorial males preside over a stretch of river and groups of five to thirty females and young hippos. During the day, they remain cool by staying in the water or mud; reproduction and birth both occur in water. They emerge at dusk to graze on grasses. While hippos rest near each other in the water, grazing is a solitary activity and hippos are not
territorial A territory is an administrative division Administrative division, administrative unitArticle 3(1). , country subdivision, administrative region, subnational entity, first-level subdivision, as well as many similar terms, are generic names f ...
on land. The hippo is among the most dangerous animals in the world due to its highly aggressive and unpredictable nature. They are threatened by habitat loss and poaching for their meat and
ivory Ivory is a hard, white material from the tusk Tusks are elongated, continuously growing front teeth A tooth (plural teeth) is a hard, calcification, calcified structure found in the jaws (or mouths) of many vertebrates and used to Mastica ...
canine teeth.


Etymology

The
Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken in the area around Rome, known as Latium. Through the power of the Roman Republic, it became ...

Latin
word ''hippopotamus'' is derived from the ancient
Greek#REDIRECT Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the Hellenic Republic, is a country located in Southeast Europe. Its population is approximately 10.7 million as of ...
, ''hippopótamos'', from , ''híppos'', "horse", and , ''potamós'', "river", meaning "horse of the river". In English, the
plural The plural (sometimes abbreviated An abbreviation (from Latin ''brevis'', meaning ''short'') is a shortened form of a word or phrase, by any method. It may consist of a group of letters, or words taken from the full version of the word or ph ...
is "hippopotamuses", but "hippopotami" is also used.


Taxonomy and origins


Classification

Hippopotamus is the
type genus In biological taxonomy the type genus is the genus Genus /ˈdʒiː.nəs/ (plural genera /ˈdʒen.ər.ə/) is a taxonomic rank In biological classification In biology, taxonomy () is the scientific study of naming, defining (Circumsc ...
of the family
Hippopotamidae :''This is the article on the family Hippopotamidae; for the main article on hippos, see Hippopotamus The hippopotamus ( ; ''Hippopotamus amphibius''), also called the hippo, common hippopotamus or river hippopotamus, is a large, mostly her ...

Hippopotamidae
. The
pygmy hippopotamus The pygmy hippopotamus (''Choeropsis liberiensis'') is a small hippopotamid which is native to the forests and swamps of West Africa West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa ...

pygmy hippopotamus
belongs to a different genus in Hippopotamidae, either ''
Choeropsis The pygmy hippopotamus (''Choeropsis liberiensis'') is a small hippopotamid which is native to the forests and swamps of West Africa West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa ...

Choeropsis
'' or ''
Hexaprotodon ''Hexaprotodon'' is a genus of Hippopotamidae that was often applied to the pygmy hippopotamus before its reclassification into the genus ''Choeropsis''. The name ''Hexaprotodon'' means "six front teeth" as some of the fossil forms have three pai ...
.'' Hippopotamidae are sometimes known as hippopotamids. Sometimes, the subfamily Hippopotaminae is used. Further, some taxonomists group hippos and
anthracotheres Anthracotheriidae is a paraphyletic family of extinct, hippopotamus-like artiodactyl ungulates related to hippopotamuses and Cetacea, whales. The oldest genus, ''Elomeryx'', first appeared during the middle Eocene in Asia. They thrived in Africa ...
in the superfamily Anthracotheroidea. Hippopotamidae are classified along with other
even-toed ungulates The even-toed ungulates (Artiodactyla , ) are ungulate Ungulates ( ) are members of the diverse clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyly, monophyletic – that is, ...
in the
order Order, ORDER or Orders may refer to: * Orderliness Orderliness is a quality that is characterized by a person’s interest in keeping their surroundings and themselves well organized, and is associated with other qualities such as cleanliness a ...
Artiodactyla The even-toed ungulates (Artiodactyla , ) are ungulate Ungulates ( ) are members of the diverse Ungulata which primarily consists of large mammals with . These include s such as s, es, and s; and s such as , s, s, s, , , and es. s such as , ...

Artiodactyla
. Other artiodactyls include
camels A camel is an even-toed ungulate in the genus ''Camelus'' that bears distinctive fatty deposits known as "humps" on its back. Camels have long been domesticated and, as livestock, they provide food (camel milk, milk and meat) and textiles (fibe ...

camels
,
cattle Cattle, taurine cattle, Eurasian cattle, or European cattle (''Bos taurus'' or ''Bos primigenius taurus'') are large domestication, domesticated Cloven hoof, cloven-hooved herbivores. They are a prominent modern member of the subfamily Bovinae ...

cattle
,
deer Deer or true deer are hoof A hoof ( or ), plural hooves ( or ) or hoofs , is the tip of a toe Toes are the digits (fingers) of the foot of a tetrapod. Animal Animals (also called Metazoa) are multicellular eukaryotic organis ...

deer
and
pigs The pig (''Sus domesticus''), often called swine, hog, or domestic pig when distinguishing from other members of the genus ''Sus (genus), Sus'', is an Omnivore, omnivorous, Domestication, domesticated even-toed ungulate, even-toed hoofed mamm ...

pigs
, although hippos are not closely related to these groups. Five subspecies of hippos have been described based on morphological differences in their skulls and geographical differences: *Great northern hippopotamus or Nile hippopotamus ''H. a. amphibius'' – (the nominate subspecies) which stretched from
Egypt Egypt ( ar, مِصر, Miṣr), officially the Arab Republic of Egypt, is a transcontinental country This is a list of countries located on more than one continent A continent is one of several large landmasses. Generally identi ...

Egypt
, where they are now extinct, south up the
Nile River The Nile, , Bohairic , lg, Kiira , Nobiin Nobiin, or Mahas, is a Northern Nubian languages, Nubian language of the Nilo-Saharan languages, Nilo-Saharan language family. "Nobiin" is the genitive case, genitive form of ''Nòòbíí'' ("Nub ...
to
Tanzania Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa East Africa or Eastern Africa is the eastern subregion of the Africa Africa is the world's second-larges ...

Tanzania
and
Mozambique Mozambique (), officially the Republic of Mozambique ( pt, Moçambique or , ; ny, Mozambiki; sw, Msumbiji; ts, Muzambhiki), is a country located in Southeastern Africa bordered by the Indian Ocean The Indian Ocean is the third-lar ...

Mozambique
*East African hippopotamus ''H. a. kiboko'' – in
Kenya ) , national_anthem = "Ee Mungu Nguvu Yetu "Ee Mungu Nguvu Yetu" (, ) is the national anthem of Kenya. History "Ee Mungu Nguvu Yetu"'s lyrics were originally written in Swahili language, Kiswahili, the national language of Kenya ...

Kenya
in the
African Great Lakes The African Great Lakes ( sw, Maziwa Makuu) are a series of lake A lake is an area filled with water, localized in a Depression (geology), basin, surrounded by land, and set apart from any river or other outlet that serves to feed or drai ...

African Great Lakes
region, and in
Somalia Somalia,, Osmanya script: 𐒈𐒝𐒑𐒛𐒐𐒘𐒕𐒖; ar, الصومال, aṣ-Ṣūmāl officially the Federal Republic of SomaliaThe ''Federal Republic of Somalia'' is the country's name per Article 1 of thProvisional Constitutio ...

Somalia
in the
Horn of Africa The Horn of Africa (HoA), also known as the Somali Peninsula, is a large peninsula of East Africa.Robert Stock, ''Africa South of the Sahara, Second Edition: A Geographical Interpretation'', (The Guilford Press; 2004), p. 26 Located on the ea ...

Horn of Africa
. Broader nasals and more hollowed interorbital region *Cape hippopotamus or South African hippopotamus ''H. a. capensis'' – from Zambia to
South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. With over 60 million people, it is the world's 23rd-most populous nation and covers an area of . South Africa has three capital citie ...

South Africa
, most flattened skull of the subspecies *West African hippopotamus or Tchad hippopotamus ''H. a. tschadensis'' – throughout Western Africa to, as the name suggests,
Chad Chad (; ar, تشاد , ; french: Tchad, ), officially known as the Republic of Chad ( ar, جمهورية تْشَاد, link=no '; ), is a landlocked A landlocked country is a country that does not have territory connected to an oce ...

Chad
, slightly shorter and wider face, with prominent orbits *Angola hippopotamus ''H. a. constrictus'' – in
Angola , national_anthem = "Angola Avante "Angola Avante" (, ) is the national anthem A national anthem is a song that officially symbolizes a country A country is a distinct territory, territorial body or political entity. It is often r ...

Angola
, the southern
Democratic Republic of Congo The Democratic Republic of the Congo ( french: République démocratique du Congo (RDC) ), also known as Congo-Kinshasa, DR Congo, the DRC, the DROC, or the Congo, and formerly Zaire Zaire (, ), officially the Republic of Zaire (frenc ...

Democratic Republic of Congo
and
Namibia Namibia (, ), officially the Republic of Namibia, is a country in Southern Africa Southern Africa is the south South is one of the cardinal directions or compass points. South is the opposite of north and is perpendicular to the east a ...

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 nonrepresentative samples. Genetic analyses have tested the existence of three of these putative subspecies. A study examining
mitochondrial DNA Mitochondrial DNA (mtDNA or mDNA) is the DNA Deoxyribonucleic acid (; DNA) is a molecule File:Pentacene on Ni(111) STM.jpg, A scanning tunneling microscopy image of pentacene molecules, which consist of linear chains of five car ...

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'' has been tested.


Evolution

Until 1909,
naturalists Natural history is a domain of inquiry involving organisms, including animals, fungus, fungi, and plants, in their natural environment, leaning more towards observational than experimental methods of study. A person who studies natural history ...

naturalists
grouped hippos with pigs, based on molar patterns. Several lines of evidence, first from blood proteins, then from
molecular systematics Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominately in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...
and
DNA Deoxyribonucleic acid (; DNA) is a molecule A scanning tunneling microscopy image of pentacene molecules, which consist of linear chains of five carbon rings. A molecule is an electrically Electricity is the set of physical ...

DNA
and the
fossil record A fossil (from Classical Latin: , literally 'obtained by digging') is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, Seashell, shells, exoskeletons, stone imprints of a ...
, show that their closest living relatives are
cetacean Cetaceans (from la, cetus Cetus () is a constellation, sometimes called 'the whale' in English. The Cetus (mythology), Cetus was a sea monster in Greek mythology which both Perseus and Heracles needed to slay. Cetus is in the region of the ...
s (
whale Whales are a widely distributed and diverse group of fully aquatic Aquatic means relating to water Water (chemical formula H2O) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is ...

whale
s,
dolphin Dolphin is the common name of aquatic mammal Aquatic and semiaquatic mammals are a diverse group of mammal Mammals (from Latin language, Latin , 'breast') are a group of vertebrate animals constituting the class (biology), class Mam ...

dolphin
s, and
porpoise Porpoises are a group of fully aquatic marine mammals, similar in appearance to a dolphin Dolphin is the common name of aquatic mammal Aquatic and semiaquatic mammals are a diverse group of mammal Mammals (from Latin language, ...

porpoise
s). The common ancestor of hippos and whales branched off from
Ruminantia Ruminantia is a taxon In biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemical processes, Molecular biology, molecular interactions, Physiology, ...

Ruminantia
and the rest of the even-toed ungulates; 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 semiaquatic ancestor that branched off from other artiodactyls around . This hypothesised ancestral group likely split into two branches around . One branch would evolve into cetaceans, possibly beginning about , with the protowhale ''
Pakicetus ''Pakicetus'' is an extinct genus Genus /ˈdʒiː.nəs/ (plural genera /ˈdʒen.ər.ə/) is a taxonomic rank In biological classification In biology, taxonomy () is the scientific study of naming, defining (Circumscription (taxonom ...
'' and other early whale ancestors collectively known as
Archaeoceti Archaeoceti ("ancient whales"), or Zeuglodontes in older literature, is a paraphyletic In taxonomy Taxonomy (general) is the practice and science of classification of things or concepts, including the principles that underlie such classif ...
, which eventually underwent
aquatic adaptation Several groups of tetrapods Tetrapods (; ) are four-limbed animals constituting the superclass Tetrapoda (). It includes extant Extant is the opposite of the word extinct Extinction is the termination of a kind of organism or of a group ...
into the completely aquatic
cetacea Cetaceans (from la, cetus Cetus () is a constellation, sometimes called 'the whale' in English. The Cetus (mythology), Cetus was a sea monster in Greek mythology which both Perseus and Heracles needed to slay. Cetus is in the region of the ...

cetacea
ns. The other branch became the
anthracotheres Anthracotheriidae is a paraphyletic family of extinct, hippopotamus-like artiodactyl ungulates related to hippopotamuses and Cetacea, whales. The oldest genus, ''Elomeryx'', first appeared during the middle Eocene in Asia. They thrived in Africa ...
, a large family of four-legged beasts, the earliest of which in the late
Eocene The Eocene ( ) Epoch is a geological epoch In chronology 222px, Joseph Scaliger's ''De emendatione temporum'' (1583) began the modern science of chronology Chronology (from Latin Latin (, or , ) is a classical language belonging to the ...
would have resembled skinny hippos with comparatively small and narrow heads. All branches of the anthracotheres, except that which evolved into
Hippopotamidae :''This is the article on the family Hippopotamidae; for the main article on hippos, see Hippopotamus The hippopotamus ( ; ''Hippopotamus amphibius''), also called the hippo, common hippopotamus or river hippopotamus, is a large, mostly her ...

Hippopotamidae
, became extinct during the
Pliocene The Pliocene ( ; also Pleiocene) epoch (geology), Epoch is the epoch in the geologic timescale that extends from 5.333 million to 2.58 A rough evolutionary lineage can be traced from Eocene and
Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define ...
species: ''
Anthracotherium ''Anthracotherium'' ("Coal Beast") was a genus of extinct Even-toed ungulate, artiodactyl ungulate mammals, characterized by having 44 teeth, with five semi-crescentic cusps on the crowns of the upper molars. The genus ranged from the middle Eocen ...
'' and ''
Elomeryx ''Elomeryx'' is an extinct genus of artiodactyl ungulate, and is among the earliest known anthracotheres. The genus was extremely widespread, first being found in Asia in the middle Eocene, in Europe during the latest Eocene, and having spread to ...
'' to the
Miocene The Miocene ( ) is the first geological epoch In geochronology, an epoch is a subdivision of the geologic timescale that is longer than an age (geology), age but shorter than a period (geology), period. The current epoch is the Holocene Epoch of ...
species ''
Merycopotamus ''Merycopotamus'' is an extinct genus of Asian anthracothere that appeared during the Middle Miocene, and died out in the Late Pliocene. At the height of the genus' influence, species ranged throughout southern Asia. With the extinction of the ...
'' and ''
Libycosaurus ''Libycosaurus'' ("Lizard Lizards (suborder In biological classification, the order ( la, wikt:ordo#Latin, ordo) is # a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. The well-known rank ...
'' and the very latest anthracotheres in the
Pliocene The Pliocene ( ; also Pleiocene) epoch (geology), Epoch is the epoch in the geologic timescale that extends from 5.333 million to 2.58 These groups lived in Eurasia and the discovery of ''Epirigenys'' in East Africa, which was likely in a
sister group In phylogenetics In biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemical processes, Molecular biology, molecular interactions, Physiology, physi ...
to Hippopotamidae, suggests that hippo ancestors entered Africa around 35 mya and were the earliest large mammals to colonise the continent. The oldest known hippopotamid is the genus ''
Kenyapotamus ''Kenyapotamus'' is a possible ancestor of living Hippopotamidae, hippopotamuses that lived roughly 16 million to 8 million years ago during the Miocene epoch. Its name reflects that its fossils were first found in modern-day Kenya. Although li ...
'', which lived in Africa from 16 to . While hippopotamid species spread across Asia and Europe, no hippos have ever been discovered in the Americas, although various anthracothere genera emigrated into North America during the early
Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define ...
. From 7.5 to , an ancestor to the modern hippo, ''
Archaeopotamus ''Archaeopotamus'' is an extinct genus of Hippopotamidae that lived between 7.5 and 2.58 million years ago in Africa and the Middle East. The genus was described in 2005 to encompass species of hippos that were previously grouped in ''Hexaprotodo ...
'', lived in Africa and the Middle East. While the fossil record of hippos is still poorly understood, the two modern genera, ''Hippopotamus'' and ''
Choeropsis The pygmy hippopotamus (''Choeropsis liberiensis'') is a small hippopotamid which is native to the forests and swamps of West Africa West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa ...

Choeropsis
'' (sometimes ''
Hexaprotodon ''Hexaprotodon'' is a genus of Hippopotamidae that was often applied to the pygmy hippopotamus before its reclassification into the genus ''Choeropsis''. The name ''Hexaprotodon'' means "six front teeth" as some of the fossil forms have three pai ...
''), may have diverged as far back as . Taxonomists disagree whether or not the modern
pygmy hippopotamus The pygmy hippopotamus (''Choeropsis liberiensis'') is a small hippopotamid which is native to the forests and swamps of West Africa West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa ...

pygmy hippopotamus
is a member of ''Hexaprotodon''—an apparently
paraphyletic In taxonomy Taxonomy (general) is the practice and science of classification of things or concepts, including the principles that underlie such classification. The term may also refer to a specific classification scheme. Originally used only ...

paraphyletic
genus, also embracing many extinct Asian hippopotamuses, that is more closely related to ''Hippopotamus''—or of ''Choeropsis'', an older and
basal Basal or basilar is a term meaning ''base'', ''bottom'', or ''minimum''. Science * Basal (anatomy), an anatomical term of location for features associated with the base of an organism or structure * Basal (medicine), a minimal level that is neces ...
genus.


Extinct species

Three species of
Malagasy hippopotamus Several species of Malagasy hippopotamus (also known as Malagasy dwarf hippopotamus, Malagasy pygmy hippopotamus or Madagascan instead of Malagasy) lived on the island of Madagascar but are now believed to be extinct. The animals were very similar ...

Malagasy hippopotamus
became extinct during the
Holocene The Holocene ( ) is the current geological epoch In geochronology, an epoch is a subdivision of the geologic timescale that is longer than an age (geology), age but shorter than a period (geology), period. The current epoch is the Holocene E ...
on
Madagascar Madagascar (; mg, Madagasikara), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), and previously known as the Malagasy Republic The Malagasy Republic ( mg, Repoblika Mal ...

Madagascar
, one of them within the past 1,000 years. The Malagasy hippos were smaller than the modern hippo, likely through the process of
insular dwarfism Insular dwarfism, a form of phyletic dwarfism Phyletic dwarfism is the decrease in average size of animals of a species. There are a few circumstances that often lead to species doing this. Lack of Predation, predators of smaller creatures can a ...
. Fossil evidence indicates many Malagasy hippos were hunted by humans, a likely factor in their eventual extinction. Isolated members of Malagasy hippos may have survived in remote pockets; in 1976, villagers described a living animal called the ''kilopilopitsofy'', which may have been a Malagasy hippo. Three species of hippopotamus, the European hippopotamus (''
Hippopotamus antiquus ''Hippopotamus antiquus'', sometimes called the European hippopotamus, was a species of Hippopotamus (genus), hippopotamus that ranged across Europe, becoming extinct some time before the last glacial period at the end of the Pleistocene epoch. Som ...
''), ''
Hippopotamus major ''Hippopotamus major'' or the giant European hippo is an extinct species of hippopotamus found in Pleistocene fossil sites in Europe and Great Britain. ''Hippopotamus major'' was one of the largest and northernmost hippopotamus species that ever li ...

Hippopotamus major
'' and ''
Hippopotamus gorgops ''Hippopotamus gorgops'' is an extinct species of hippopotamus. It first appeared in Africa during the late Pliocene, and eventually migrated into Europe during the early Pleistocene (where its fossils were first discovered). It became extinct du ...

Hippopotamus gorgops
'', ranged throughout continental Europe and the British Isles. All three species became extinct before the last glaciation. Ancestors of European hippos found their way to many islands of the
Mediterranean Sea The Mediterranean Sea is a connected to the , surrounded by the and almost completely enclosed by land: on the north by and and , on the south by , and on the east by the . The Sea has played a central role in the . Although the Mediterrane ...
during the
Pleistocene The Pleistocene ( , often referred to as the ''Ice Age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the earth’s most recent period of repeated glaciations. Before a change finally ...
. The Pleistocene also saw a number of dwarf species evolve on several Mediterranean islands, including
Crete Crete ( el, Κρήτη, translit=, Modern Modern may refer to: History *Modern history Human history, also known as world history, is the description of humanity's past. It is informed by archaeology Archaeology or archeology ...

Crete
(''
Hippopotamus creutzburgi ''Hippopotamus creutzburgi'', the Cretan dwarf hippopotamus, is an extinct species of hippopotamus The hippopotamus ( ; ''Hippopotamus amphibius''), also called the hippo, common hippopotamus or river hippopotamus, is a large, mostly herbi ...
''),
Cyprus Cyprus ; tr, Kıbrıs (), officially called the Republic of Cyprus,, , lit: Republic of Cyprus is an island country An island country or an island nation is a country A country is a distinct territory, territorial body or poli ...

Cyprus
(the
Cyprus dwarf hippopotamus The Cyprus dwarf hippopotamus or Cypriot pygmy hippopotamus (''Hippopotamus minor'') is an extinct species of hippopotamus The hippopotamus ( ; ''Hippopotamus amphibius''), also called the hippo, common hippopotamus or river hippopotamus, ...
, ''Hippopotamus minor''),
Malta Malta ( , , ), officially known as the Republic of Malta ( mt, Repubblika ta' Malta ) and formerly Melita, is a Southern European island country consisting of an archipelago in the Mediterranean Sea. It lies south of Italy, east of Tunisi ...

Malta
(''
Hippopotamus melitensis ''Hippopotamus melitensis'' is an extinct Hippopotamidae, hippopotamus from Malta. It arrived after the Messinian salinity crisisHunt, Christopher O., Schembri, Patrick J.Quaternary Environments and Biogeography of the Maltese Islands page 31, a ...
''), and
Sicily (man) it, Siciliana (woman) , population_note = , population_blank1_title = , population_blank1 = , demographics_type1 = Ethnicity , demographics1_footnotes = , demographi ...

Sicily
(''
Hippopotamus pentlandi ''Hippopotamus pentlandi'' is an extinct Hippopotamidae, hippopotamus from Sicily. It arrived during the Pleistocene, in the Messinian salinity crisis. It is the largest of the insular dwarf hippos known from the Pleistocene of the Mediterranean ...

Hippopotamus pentlandi
''). Of these, the Cyprus dwarf hippo survived until the end of the Pleistocene or early Holocene. Evidence from an archaeological site,
Aetokremnos Aetokremnos is a rock shelter near Limassol Limassol (; el, Λεμεσός, Lemesós ; tr, Limasol or ) is a city on the southern coast of Cyprus and capital of the Limassol District, district with the same name. Limassol is the second largest ur ...
, continues to cause debate on whether or not the species was encountered, and was driven to extinction, by man. Across Eurasia, the hippopotamus became extinct between 50,000-16,000 years ago.


Characteristics and adaptations

Hippos are among the largest living land mammals, being only smaller than
elephant Elephants are the largest existing land animals. Three living species In biology, a species is the basic unit of biological classification, classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A specie ...

elephant
s and some
rhinoceros A rhinoceros (, , ), commonly abbreviated to rhino, is a member of any of the five extant Extant is the opposite of the word extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. T ...

rhinoceros
es. Among the extant African
megafauna In terrestrial zoology Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the Animal, animal kingdom, including the anatomy, structure, embryology, e ...

megafauna
, behind the two African elephant species, they average smaller than the
white rhinoceros The white rhinoceros or square-lipped rhinoceros (''Ceratotherium simum'') is the largest extant species of rhinoceros. It has a wide mouth used for grazing (behaviour), grazing and is the most social of all rhino species. The white rhinoceros c ...

white rhinoceros
but are larger by body mass than the
black rhinoceros The black rhinoceros or hook-lipped rhinoceros (''Diceros bicornis'') is a species of rhinoceros A rhinoceros (, , ), commonly abbreviated to rhino, is a member of any of the five extant Extant is the opposite of the word extinct. It may ...
and the
giraffe The giraffe is a tall African mammal Mammals (from Latin Latin (, or , ) is a classical language A classical language is a language A language is a structured system of communication Communication (from Latin ''c ...

giraffe
. Hippos measure long, including a tail of about in length and tall at the shoulder. Mean adult weight is around and for males and females respectively, very large males can reach and exceptional males weighing , and (in captivity) have been reported. Male hippos appear to continue growing throughout their lives while females reach maximum weight at around age 25. Hippos have barrel-shaped bodies with short legs and long muzzles. Their skeletal structures are graviportal, adapted to carrying their enormous weight, and their
specific gravity Relative density, or specific gravity, is the ratio In mathematics, a ratio indicates how many times one number contains another. For example, if there are eight oranges and six lemons in a bowl of fruit, then the ratio of oranges to lemon ...
allows them to sink and move along the bottom of a river. Hippopotamuses have small legs (relative to other
megafauna In terrestrial zoology Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the Animal, animal kingdom, including the anatomy, structure, embryology, e ...

megafauna
) because the water in which they live reduces the weight burden. Though they are bulky animals, hippos can gallop at on land but normally trot. They are incapable of jumping but do climb up steep banks. Despite being semiaquatic and having webbed feet, an adult hippo is not a particularly good swimmer nor can it float. It is rarely found in deep water; when it is, the animal moves by porpoise-like leaps from the bottom. Adult hippos move at speeds up to in water; typically resurfacing to breathe every three to five minutes. The young have to breathe every two to three minutes. The process of surfacing and breathing is unconscious: a hippo sleeping underwater will rise and breathe without waking up. A hippo closes its nostrils when it goes beneath the surface of the water. The eyes, ears, and nostrils of hippos are placed high on the roof of their skulls. This allows these organs to remain above the surface while the rest of the body submerges. The testes of the males descend only partially and a scrotum is not present. In addition, the penis retracts into the body when not . The genitals of the female hippos are unusual in that the vagina is ridged and two large
diverticula In medicine or biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemical processes, Molecular biology, molecular interactions, Physiology, physiolog ...
protrude from the
vulval vestibule The vulval vestibule (or vulvar vestibule or vestibule of vagina) is a part of the vulva The vulva (plural: vulvas or vulvae; derived from Latin for wrapper or covering) consists of the external female sex organs. The vulva includes the mo ...

vulval vestibule
. The function of these is unknown. The hippo's jaw is powered by a large
masseter In human anatomy, the masseter is one of the muscles of mastication There are four classical muscles of mastication. During mastication, three muscles of mastication (''musculi masticatorii'') are responsible for adduction of the jaw, and one ( ...

masseter
and a well-developed
digastric The digastric muscle (also digastricus) (named ''digastric'' as it has two 'bellies') is a small muscle Muscle is a soft tissue found in most animals. Muscle cells contain protein Proteins are large biomolecules or macromolecules that a ...
; the latter loops up behind the former to the
hyoid The hyoid bone (lingual bone or tongue-bone) () is a horseshoe A horseshoe is a fabricated product, normally made of metal A metal (from Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ε ...
. The jaw hinge is located far back enough to allow the animal to open its mouth at almost 180°. A moderate folding of the
orbicularis oris muscle In human anatomy The human body is the structure of a human being Humans (''Homo sapiens'') are the most abundant and widespread species In biology, a species is the basic unit of biological classification, classification and a ...
allows the hippo to achieve such a gape without tearing any tissue. The bite
force In physics, a force is an influence that can change the motion (physics), motion of an Physical object, object. A force can cause an object with mass to change its velocity (e.g. moving from a Newton's first law, state of rest), i.e., to acce ...

force
of an adult female hippo has been measured as . Hippo teeth sharpen themselves as they grind together. The lower
canines Canine may refer to: Zoology * dog-like mammals (i.e. members of the canid subfamily Caninae) ** ''Canis'', a genus including dogs, wolves, coyotes, and jackals ** Dog, the domestic dog * Canine tooth, in mammalian oral anatomy Other uses * Cani ...
and lower
incisor Incisors (from Latin ''incidere'', "to cut") are the front teeth A tooth (plural teeth) is a hard, calcified Calcification is the accumulation of calcium salts in a Tissue (biology), body tissue. It normally occurs in the formation of bone ...
s are enlarged, especially in males, and grow continuously. The incisors can reach , while the canines reach up to . The canines and incisors are used for combat and play no role in feeding. Hippos rely on their broad horny lips to grasp and pull grasses which are then ground by the
molars The molars or molar teeth are large, flat teeth A tooth (plural teeth) is a hard, calcified Calcification is the accumulation of calcium salts in a Tissue (biology), body tissue. It normally occurs in the formation of bone, but calcium ...
. The hippo is considered to be a
pseudoruminant Pseudoruminant is a classification of animals based on their digestive tract differing from the ruminant Ruminants (suborder Ruminantia) are large ungulate, hoofed herbivorous grazing or browsing mammals that are able to acquire nutrients from p ...
; it has a complex three-chambered stomach but does not "chew
cud Cud is a portion of food that returns from a ruminant Ruminants (suborder Ruminantia) are large ungulate, hoofed herbivorous grazing or browsing mammals that are able to acquire nutrients from plant-based food by Enteric fermentation, fermenti ...
". Unlike most other semiaquatic animals, hippos have very little hair. The skin is thick, providing it great protection against
conspecifics Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organis ...
and predators. By contrast, its
subcutaneous fat The subcutaneous tissue (), also called the hypodermis, hypoderm (), subcutis, superficial fascia, is the lowermost layer of the integumentary system The integumentary system is the set of organs forming the outermost layer of an animal's bod ...
layer is thin. The animals' upper parts are purplish-grey to blue-black, while the under parts and areas around the eyes and ears can be brownish-pink. Their skin secretes a natural
sunscreen Sunscreen, also known as sunblock or suntan lotion, is a photoprotective topical A topical medication is a medication A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug use ...
substance which is red-coloured. The secretion is sometimes referred to as "blood sweat", but is neither blood nor sweat. This secretion is initially colourless and turns red-orange within minutes, eventually becoming brown. Two distinct
pigment A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compound , CH4; is among the simplest organic compou ...
s have been identified in the secretions, one red () and one orange (norhipposudoric acid). The two pigments are highly acidic compounds. They inhibit the growth of disease-causing bacteria, and their light absorption peaks in the
ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation In physics Physics is the natural science that studies matter, its Elementary particle, fundamental constituents, its Motion (physics), motion and behavior through Spacetime, ...

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 synthesise the pigments from precursors such as the
amino acid Amino acids are organic compound In , organic compounds are generally any s that contain - . Due to carbon's ability to (form chains with other carbon s), millions of organic compounds are known. The study of the properties, reactions, a ...

amino acid
tyrosine -Tyrosine or tyrosine (symbol Tyr or Y) or 4-hydroxyphenylalanine is one of the 20 standard amino acid Amino acids are organic compound , CH4; is among the simplest organic compounds. In chemistry, organic compounds are generally any chemi ...

tyrosine
. Nevertheless, this natural sunscreen cannot prevent the animal's skin from cracking if it stays out of water too long. The secretion does help regulate the body temperature of the hippo and acts as an antibiotic. A hippo's lifespan is typically 40–50 years. Donna the Hippo was one of the oldest living hippos in captivity. She lived at the
Mesker Park Zoo The Mesker Park Zoo and Botanic Garden is a zoo that opened in 1928 in Evansville, Indiana, United States. It is located in Mesker Park on Evansville's northwest side and is run by the City of Evansville. The Mesker Park Zoo and Botanic Garden ...
in
Evansville, Indiana Evansville is a city in and the county seat A county seat is an administrative centerAn administrative centre is a seat of regional administration or local government Local government is a generic term for the lowest tiers of public adminis ...
, in the US until her death in 2012 at the age of 61. The oldest hippo recorded was called Bertha; she had lived in the
Manila Zoo The Manila Zoo, formally known as the Manila Zoological and Botanical Garden, is a zoo located in Malate, Manila, Malate, Manila, Philippines that opened on July 25, 1959. History The Manila Zoological and Botanical Garden first opened to the ...
in the Philippines since it first opened in 1959. When she died in 2017, her age was estimated to be 65.


Distribution and status

''Hippopotamus amphibius'' was widespread in
North Africa North Africa or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in th ...

North Africa
and
Europe Europe is a continent A continent is any of several large landmass A landmass, or land mass, is a large region In geography Geography (from Greek: , ''geographia'', literally "earth description") is a field of scienc ...

Europe
during the
Eemian The Eemian (also called the last interglacial, Sangamonian Stage, Ipswichian, Mikulin, Kaydaky, penultimate,NOAA - Penultimate Interglacial Period http://www.ncdc.noaa.gov/global-warming/penultimate-interglacial-period Valdivia or Riss-Würm) wa ...
and late Pleistocene until about 30,000 years ago. Archaeological evidence exists of its presence in the
Levant The Levant () is an term referring to a large area in the region of . In its narrowest sense, it is equivalent to the , which included present-day , , , , and most of southwest of the middle . In its widest historical sense, the Levant ...

Levant
, dating to less than 3,000 years ago. The species was common in
Egypt Egypt ( ar, مِصر, Miṣr), officially the Arab Republic of Egypt, is a transcontinental country This is a list of countries located on more than one continent A continent is one of several large landmasses. Generally identi ...

Egypt
's
Nile The Nile, , Bohairic , lg, Kiira , Nobiin Nobiin, or Mahas, is a Northern Nubian languages, Nubian language of the Nilo-Saharan languages, Nilo-Saharan language family. "Nobiin" is the genitive case, genitive form of ''Nòòbíí'' ("Nub ...

Nile
region during
antiquity Antiquity or Antiquities may refer to Historical objects or periods Artifacts *Antiquities Antiquities are objects from antiquity Antiquity or Antiquities may refer to Historical objects or periods Artifacts * Antiquities, objects or arti ...
, but has since been extirpated.
Pliny the Elder #REDIRECT Pliny the Elder #REDIRECT Pliny the Elder#REDIRECT Pliny the Elder Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, a naturalist Natural history is a domain of inquiry involving organisms, includi ...

Pliny the Elder
writes that, in his time, the best location in Egypt for capturing this animal was in the Saite nome;
English translation
the animal could still be found along the
Damietta Damietta ( ar, دمياط ', ; cop, ⲧⲁⲙⲓⲁϯ, Tamiati) is a harbor, port city and the capital of the Damietta Governorate in Egypt, a former Diocese, bishopric and present multiple Catholic titular see. It is located at the Damietta ...

Damietta
branch after the Arab Conquest in 639. Reports of the slaughter of the last hippo in
Natal Province The Province of Natal ( af, Natalprovinsie), commonly called Natal, was a province A province is almost always an administrative division Administrative division, administrative unitArticle 3(1). , country subdivision, administrative reg ...
were made at the end of the 19th century. Hippos are still found in the rivers and lakes of the northern
Democratic Republic of the Congo The Democratic Republic of the Congo ( french: République démocratique du Congo (RDC) ), also known as Congo-Kinshasa, DR Congo, the DRC, the DROC, or the Congo, and formerly Zaire Zaire (, ), officially the Republic of Zaire (frenc ...

Democratic Republic of the Congo
,
Uganda Uganda (Ugandan Languages: Yuganda), officially the Republic of Uganda ( sw, Jamhuri ya Uganda), is a landlocked A landlocked country is a country that does not have territory connected to an ocean or whose coastlines lie on endorheic ba ...

Uganda
,
Tanzania Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa East Africa or Eastern Africa is the eastern subregion of the Africa Africa is the world's second-larges ...

Tanzania
and
Kenya ) , national_anthem = "Ee Mungu Nguvu Yetu "Ee Mungu Nguvu Yetu" (, ) is the national anthem of Kenya. History "Ee Mungu Nguvu Yetu"'s lyrics were originally written in Swahili language, Kiswahili, the national language of Kenya ...

Kenya
, north through to
Ethiopia Ethiopia, officially the Federal Democratic Republic of Ethiopia, is a landlocked country A landlocked country is a country A country is a distinct territory, territorial body or political entity. It is often referred to as the ...

Ethiopia
,
Somalia Somalia,, Osmanya script: 𐒈𐒝𐒑𐒛𐒐𐒘𐒕𐒖; ar, الصومال, aṣ-Ṣūmāl officially the Federal Republic of SomaliaThe ''Federal Republic of Somalia'' is the country's name per Article 1 of thProvisional Constitutio ...

Somalia
and
Sudan Sudan ( or ; ar, السودان, as-Sūdān), officially the Republic of the Sudan ( ar, جمهورية السودان, link=no, Jumhūriyyat as-Sūdān), is a country in Northeast Africa. It borders the countries of Central African Republ ...

Sudan
, west to
The Gambia The Gambia (), officially the Republic of The Gambia, is a country in West Africa. It is the smallest country within mainland AfricaHoare, Ben. (2002) ''The Kingfisher A-Z Encyclopedia'', Kingfisher Publications. p. 11. . and is surrounded by ...
, and south to
South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. With over 60 million people, it is the world's 23rd-most populous nation and covers an area of . South Africa has three capital citie ...

South Africa
. Genetic evidence suggests that common hippos in Africa experienced a marked population expansion during or after the
Pleistocene The Pleistocene ( , often referred to as the ''Ice Age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the earth’s most recent period of repeated glaciations. Before a change finally ...
, 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. Hippos are also subject to unregulated hunting and
poaching Poaching has been defined as the illegal hunting Hunting is the practice of seeking, pursuing and capturing or killing wildlife Wildlife traditionally refers to undomesticated animal Animals (also called Metazoa) are ...
. In May 2006, the hippo was identified as a
vulnerable species A vulnerable species is a species In biology, a species is the basic unit of biological classification, classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group o ...
on the
IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species (also known as the IUCN Red List or Red Data Book), founded in 1964, is the world's most comprehensive inventory of the global Conservation movement, conser ...
drawn up by the
International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization An international organization (also known as an international institut ...
(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.
Zambia Zambia (), officially the Republic of Zambia ( Bemba:'' Icalo ca Zambia''; Tonga Tonga (, ), officially named the Kingdom of Tonga ( to, Puleʻanga Fakatuʻi ʻo Tonga), is a Polynesia Polynesia (, ; from grc, πολύς "many" ...

Zambia
(40,000) and Tanzania (20,000–30,000) possess the largest populations. The hippo population declined most dramatically in the Democratic Republic of the Congo. By 2005, the population in
Virunga National Park Virunga National Park is a national park in the Albertine Rift Valley in the eastern part of the Democratic Republic of the Congo. It was created in 1925 and is among the first protected areas in Africa. In elevation, it ranges from in the Semlik ...
had dropped to 800 or 900 from around 29,000 in the mid-1970s. The decline is attributed to the disruptions caused by the
Second Congo War The second (symbol: s, abbreviation: sec) is the base unit of time Time is the indefinite continued sequence, progress of existence and event (philosophy), events that occur in an apparently irreversible process, irreversible succession fr ...
. The poachers are believed to be
Mai-Mai The term Mai-Mai or Mayi-Mayi refers to any kind of community-based militia group active in the Democratic Republic of the Congo The Democratic Republic of the Congo ( french: République démocratique du Congo (RDC) ), also known as Cong ...
rebels, poorly paid Congolese soldiers, and local militia groups. Reasons for poaching include the belief that hippos are harmful to society, as well as financial gain. However, as of 2016, the Virunga hippo population appears to have increased, possibly due to greater enforcement and cooperation between fishermen and park authorities. The sale of hippo meat is illegal, but black-market sales are difficult for Virunga National Park officers to track. Hippo meat is considered a delicacy in some areas of central Africa and the teeth have become a valued substitute for elephant ivory.


Invasive potential

In the late 1980s,
Pablo Escobar Pablo Emilio Escobar Gaviria (; ; 1 December 19492 December 1993) was a Colombian drug lord and narcoterrorist who was the founder and sole leader of the Medellín Cartel. Dubbed "the King of Cocaine," Escobar is the wealthiest criminal in h ...
kept four hippos in a private menagerie at his residence in , east of
Medellín Medellín ( or ), officially the Municipality of Medellín ( es, Municipio de Medellín), is the second-largest city in Colombia Colombia ( , ; ), officially the Republic of Colombia, is a transcontinental country This is a list of ...

Medellín
,
Colombia Colombia ( , ; ), officially the Republic of Colombia, is a transcontinental country This is a list of countries located on more than one continent A continent is one of several large landmasses. Generally identified by conv ...

Colombia
, after buying them in
New Orleans New Orleans (,New Orleans
. They were deemed too difficult to seize and move after Escobar's death in 1993, 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 The Magdalena River ( es, Río Magdalena, ; less commonly ) is the main river of Colombia, flowing northward about through the western half of the country. It takes its name from the biblical figure Mary Magdalene. It is navigable through much of ...
. In 2009, two adults and one calf left their herd and, after attacking humans and killing cattle, one of the adults (called "Pepe") was killed by hunters under authorisation of the local authorities. When a photo of the dead hippo became public, it caused considerable controversy among animal rights groups both within the country and abroad, and further plans of culling ceased. Alternative methods have been considered, but they are unproven, or difficult and expensive. A wild male hippo was caught, castrated and released again, but it cost about US$50,000. As of 2020, there were no plans by the local government on managing the population, but further studies on their effect on the habitat have been initiated. Because of the fast-growing population, conservationists have recommended that a management plan needs to be rapidly developed. Scientists say these hippos are breeding voraciously and are an increasing menace so they must be
culled In biology, culling is the process of segregating organisms from a group according to desired or undesired characteristics. In animal breeding, it is the process of removing or segregating animals from a breeding stock based on specific trai ...
. In the U.S.,
Representative Representative may refer to: Politics *Representative democracy Representative democracy, also known as indirect democracy, is a type of democracy where elected persons represent Represent may refer to: * Represent (Compton's Most Wanted alb ...
Robert F. Broussard of Louisiana introduced the "American Hippo Bill" in 1910 to authorise the importation and release of hippopotamus into the bayous of Louisiana. Broussard argued that the hippos would eat the invasive
water hyacinth ''Pontederia crassipes'' - commonly known as common water hyacinth, (and also known as the "terror of Bengal"; generally in Bengali it is often called 'kochuripana') - is an aquatic plant native to the Amazon basin The Amazon Basin i ...

water hyacinth
that was clogging the rivers and also produce meat to help solve the American meat crisis. The chief collaborators and proponents of Broussard's bill were Major
Frederick Russell Burnham Frederick Russell Burnham DSO DSO may refer to: Organisations * Defence Science Organisation, now known as DSO National Laboratories, Singapore * Defense Sciences Office, part of the US Defense Advanced Research Projects Agency * Directorate o ...
and Captain Fritz Duquesne. Former President
Theodore Roosevelt Theodore Roosevelt Jr. ( ; October 27, 1858 – January 6, 1919), often referred to as Teddy or his initials T. R., was an American politician, statesman, conservationist, naturalist, historian, and writer who served as the 26th president o ...

Theodore Roosevelt
backed the plan, as did the U.S. Department of Agriculture, ''
The Washington Post ''The Washington Post'' (also known as the ''Post'' and, informally, ''WaPo'') is an American daily newspaper A newspaper is a Periodical literature, periodical publication containing written News, information about current events and is ...

The Washington Post
'', and ''
The New York Times ''The New York Times'' is an American daily newspaper based in New York City with a worldwide readership. Founded in 1851, the ''Times'' has since won List of Pulitzer Prizes awarded to The New York Times, 132 Pulitzer Prizes, the most of a ...

The New York Times
'', which praised hippo meat as "lake cow bacon". The "American Hippo Bill" fell just short of being passed.


Behaviour and ecology

Hippos differ from all other large land mammals, being of semiaquatic habits, and spending their days in lakes and rivers. They can be found in both savannah and forest areas. Proper habitat requires enough water to submerge in and grass nearby. Larger densities of the animals inhabit quiet waters with mostly firm, smooth sloping beaches. Male hippos may be found in very small numbers in
rapid Rapids are sections of a river where the river bed has a relatively steep gradient In vector calculus Vector calculus, or vector analysis, is concerned with differentiation Differentiation may refer to: Business * Differentiation (ec ...

rapid
waters in rocky gorges. Hippos mostly live in freshwater habitats, however populations in West Africa mostly inhabit
estuarine An estuary is a partially enclosed coastal body of brackish water Brackish water, also sometimes termed brack water, is water occurring in a natural environment having more salinity File:IAPSO Standard Seawater.jpg, upInternational Associatio ...
waters and may even be found at sea. Most of a hippo's life occurs in the water. They spend up to 16 hours a day in water as a way to stay cool, and travel inland at dusk, sometimes up to , to graze on short grasses, their main source of food. They spend four to five hours grazing and can consume of grass each night. Like most herbivores, hippos will consume a variety of plants if presented with them, but their diet in nature consists almost entirely of grass, with only minimal consumption of aquatic plants. Because of their size and their habit of taking the same paths to feed, hippos can have a significant impact on the land across which they walk, both by keeping the land clear of vegetation and depressing the ground. Over prolonged periods, hippos can divert the paths of swamps and channels. On occasion, hippos have been filmed eating
carrion Carrion (from Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken in the area around Rome, known as Latium. Through the power of the R ...

carrion
, usually near the water. There are other reports of meat-eating, and even
cannibalism Cannibalism is the act of consuming another individual of the same species as food Food is any substance consumed to provide Nutrient, nutritional support for an organism. Food is usually of plant, animal or Fungus, fungal origin, and con ...

cannibalism
and
predation Predation is a biological interaction In ecology Ecology (from el, οἶκος, "house" and el, -λογία, label=none, "study of") is the study of the relationships between living organisms, including humans, and their physical en ...

predation
. The stomach anatomy of a hippo is not suited to carnivory, and meat-eating is likely caused by aberrant behaviour or nutritional stress.


Social spacing

Studying the interaction of males and females has long been complicated because hippos are not
sexually dimorphic Sexual dimorphism is the condition where the sexes of the same species exhibit different characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. Differences may i ...
; thus females and young males are almost indistinguishable in the field. Although hippos lie close to each other, they do not seem to form social bonds except between mothers and daughters, and they are not social animals. The reason they huddle close together is unknown. Hippos are territorial only in water, where the dominant bull also known as a "beachmaster" presides over a small stretch of river, on average in length, and containing 10 females. The largest pods can contain over 100 hippos. Younger bachelors are allowed in a beachmaster's stretch, as long as they behave submissively toward him. The territories of hippos exist to establish mating rights. Within the pods, the hippos tend to segregate by sex. Bachelors lounge near other bachelors, females with other females, and the beachmaster is on his own. When hippos emerge from the water to graze, they do so individually. Hippos mark their territory by defecation. While depositing the faeces, hippos spin their tails to distribute their excrement over a greater area. "Yawning" serves as a threat display. When fighting, males use their incisors to block each other's attacks and their large canines to inflict injuries. When hippos become over-populated or a habitat is reduced, males sometimes attempt
infanticide Infanticide (or infant homicide) is the intentional killing of infants or offspring. Infanticide was a widespread practice throughout human history that was mainly used to dispose of unwanted children, its main purpose the prevention of resource ...

infanticide
, but this behaviour is not common under normal conditions. Incidents of hippo cannibalism have been documented, but this is believed to be the behaviour of distressed or sick hippos. Hippos appear to communicate vocally, through grunts and bellows, and they may practice , but the purpose of these vocalisations is currently unknown. Hippos have the unique ability to hold their heads partially above the water and send out a cry that travels through both water and air; individuals respond above and under water. Hippos will also express threat and alarm with exhalations.


Reproduction

Female hippos reach sexual maturity at five to six years and have a
gestation period 300px, A pregnant lioness. In mammals, pregnancy is the period of reproduction during which a female carries one or more live offspring from Implantation (human embryo), implantation in the uterus through gestation. It begins when a fertilisatio ...
of eight months. A study of
endocrine system The endocrine system is a messenger system comprising feedback loops of the hormone A hormone (from the Greek participle , "setting in motion") is any member of a class of signaling molecules in multicellular organisms, that are transported ...

endocrine system
s revealed that female hippos may begin puberty as early as three or four years. Males reach maturity at around 7.5 years. A study of hippo reproductive behaviour 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 The estrous cycle (, originally ) is the set of recurring physiological changes that are induced by s in most ian n s or non primates. Estrous cycles start after in females and are interrupted by anestrous phases, otherwise known as "rest" pha ...
; as with most large mammals, male hippo
spermatozoa A spermatozoon (pronounced , alternate spelling spermatozoön; plural spermatozoa; from grc, σπέρμα ("seed") and grc, ζῷον ("living being")) is a motile Motility is the ability of an organism In biology, an organism () ...

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 hippo will typically not begin ovulation again for 17 months. Mating occurs in the water, with the female submerged for most of the encounter, her head emerging periodically to draw breath. Female hippos isolate themselves to give birth and return within 10–14 days. Calves are born underwater at a weight between and an average length of around , and must swim to the surface to take their first breaths. A mother typically gives birth to only one calf, although twins also occur. The young often rest on their mothers' backs when the water is too deep for them, and they swim under water to suckle. They suckle on land when the mother leaves the water. Mother hippos are very protective of their young and may keep others at a distance, including the beachmaster who is the father of the calf. However, calves are occasionally left in nurseries which are guarded by one or a few adults. Calves in nurseries engage in playfights.
Weaning Weaning is the process of gradually introducing an infant An infant (from the Latin word ''infans'', meaning 'unable to speak' or 'speechless') is the more formal or specialised synonym for the common term ''baby'', meaning the very y ...
starts between six and eight months after birth, and most calves are fully weaned after a year. Like many other large mammals, hippos are described as
K-strategists In ecology Ecology (from el, οἶκος, "house" and el, -λογία, label=none, "study of") is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms ...
, in this case typically producing just one large, well-developed infant every couple of years (rather than many small, poorly developed young several times per year as is common among small mammals such as rodents).


Interspecies interactions

Hippos coexist with a variety of large predators.
Nile crocodile The Nile crocodile (''Crocodylus niloticus'') is a large crocodilia Crocodilia (or Crocodylia, both ) is an order Order or ORDER or Orders may refer to: * Orderliness Orderliness is associated with other qualities such as cleanliness Cl ...

Nile crocodile
s,
lion The lion (''Panthera leo'') is a large cat The cat (''Felis catus'') is a domestic Domestic may refer to: In the home * Anything relating to the human home A home, or domicile, is a space used as a permanent or semi-perma ...

lion
s and
spotted hyena The spotted hyena (''Crocuta crocuta''), also known as the laughing hyena, is a hyena Hyenas, or hyaenas (from Ancient Greek , ), are feliformia, feliform carnivoran mammals of the family Hyaenidae . With only four extant species (each in t ...

spotted hyena
s are known to prey on young hippos. However, due to their aggression and size, adult hippos are not usually preyed upon by other animals. Cases where large lion prides have successfully preyed on adult hippos have been reported but it is generally rare. Lions occasionally prey on adults at
Gorongosa National Park Gorongosa National Park is at the southern end of the Great African Rift Valley File:East Africa Rift System GPS and stresses.png, Main rift faults, plates, plate boundaries, GPS plate velocities between adjacent blocks and minimum horizontal st ...
and calves are sometimes taken at Virunga.
Crocodile Crocodiles (family In , family (from la, familia) is a of people related either by (by recognized birth) or (by marriage or other relationship). The purpose of families is to maintain the well-being of its members and of society. I ...

Crocodile
s are frequent targets of hippo aggression, probably because they often inhabit the same
riparian A riparian zone or riparian area is the interface between land and a river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the gro ...
habitats; crocodiles may be either aggressively displaced or killed by hippos. In turn, beyond cases of killing the seldom unguarded hippo calf, very large Nile crocodiles have been verified to occasionally prey on "half-grown" hippos—and based only on anecdotal evidence-possibly also adult female hippos. Aggregations of crocodiles have also been seen to dispatch still-living male hippos that have been previously injured in mating battles with other males. As with fish and turtles on a coral reef, hippos occasionally visit cleaning stations and signal, by opening their mouths wide, their readiness for being cleaned of parasites by certain species of fishes. This is an example of mutualism, in which the hippo benefits from the cleaning while the fish receive food. Hippo defecation creates
allochthonous River ecosystem An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Ene ...
deposits of organic matter along the river beds. These deposits have an unclear ecological function. A 2015 study concluded that hippo dung provides nutrients from terrestrial material for fish and aquatic invertebrates, while a 2018 study found that their dung can be toxic to aquatic life in large quantities, due to absorption of dissolved oxygen in water bodies.


Hippos and humans

The earliest evidence of human interaction with hippos comes from butchery cut marks on hippo bones at
Bouri Formation The Bouri Formation is a sequence of sedimentary deposits that is the source of australopithecine and Homo (that is, hominin) fossils, Artifact (archaeology), artifacts, and bones of large mammals with cut marks from butchery with tools by early ...
dated around 160,000 years ago. Later rock paintings and engravings showing hippos being hunted have been found in the mountains of the central
Sahara The Sahara (, ; ar, الصحراء الكبرى, ', 'the Greatest Desert') is a desert on the African continent Africa is the world's second-largest and second-most populous continent A continent is any of several large landma ...

Sahara
dated 4,000–5,000 years ago near
Djanet Djanet ( ar, جانت) is an oasis In geography, an oasis (, plural oases, ) is a fertile land in a desert or semi-desert environment.
in the Tassili n'Ajjer Mountains. The
ancient Egypt Ancient Egypt was a civilization  A civilization (or civilisation) is a that is characterized by , , a form of government, and systems of communication (such as ). Civilizations are intimately associated with additional char ...

ancient Egypt
ians recognised the hippo as a ferocious denizen of the
Nile The Nile, , Bohairic , lg, Kiira , Nobiin Nobiin, or Mahas, is a Northern Nubian languages, Nubian language of the Nilo-Saharan languages, Nilo-Saharan language family. "Nobiin" is the genitive case, genitive form of ''Nòòbíí'' ("Nub ...

Nile
and representations on the tombs of nobles show that the animals were hunted. The hippo was also known to the
Greeks The Greeks or Hellenes (; el, Έλληνες, ''Éllines'' ) are an ethnic group An ethnic group or ethnicity is a grouping of people A people is any plurality of person A person (plural people or persons) is a being that has cer ...
and
Romans Roman or Romans most often refers to: *Rome , established_title = Founded , established_date = 753 BC , founder = King Romulus , image_map = Map of comune of Rome (metropolitan city of Capital Rome, region Laz ...
. The Greek historian
Herodotus Herodotus ( ; grc, Ἡρόδοτος, Hēródotos, ; BC) was an Classical Greece, ancient Greek writer, geographer, and historian born in the Greek city of Halicarnassus, part of the Achaemenid Empire, Persian Empire (now Bodrum, Turkey). He ...
described the hippo in '' The Histories'' (written ''
circa Circa (or c.) is a Latin word meaning "about" or "around". Circa or CIRCA may also refer to: * CIRCA (art platform), art platform based in London * Circa (band) Circa (stylized as ''CIRCA:'') is a progressive rock Supergroup (music), supergroup f ...
'' 440 BC) and the Roman naturalist
Pliny the Elder #REDIRECT Pliny the Elder #REDIRECT Pliny the Elder#REDIRECT Pliny the Elder Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, a naturalist Natural history is a domain of inquiry involving organisms, includi ...

Pliny the Elder
wrote about the hippo in his encyclopedia ''
Naturalis Historia The ''Natural History'' ( la, Naturalis Historia) is a work by Pliny the Elder #REDIRECT Pliny the Elder #REDIRECT Pliny the Elder#REDIRECT Pliny the Elder Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, ...
'' (written ''circa'' 77 AD). The
Yoruba people The Yoruba people () are a Sub-Saharan Africa Sub-Saharan Africa (commonly called Black Africa) is, geographically, the area of the continent of Africa that lies south of the Sahara. According to the United Nations, it consists of all lis ...
called the hippo ''erinmi'', which means "elephant of the water". According to
Robert Baden-Powell Lieutenant-general (United Kingdom), Lieutenant General Robert Stephenson Smyth Baden-Powell, 1st Baron Baden-Powell, ( ; 22 February 1857 – 8 January 1941), was a British Army officer, writer, founder and first Chief Scout (The Scout ...
,
Zulu Zulu may refer to: Zulu people * Zulu Kingdom or Zulu Empire, a former monarchy in what is now South Africa * Zulu language, a Bantu language spoken in southern Africa * Zulu people, an ethnic group of southern Africa Arts, entertainment, and med ...
warriors referred to hippos in war chants.


Attacks on humans

The hippo is considered to be extremely aggressive and has frequently been reported charging and attacking boats. Small boats can easily be capsized by hippos and passengers can be injured or killed by the animals or drown. In one 2014 case in Niger, a boat was capsized by a hippo and 13 people were killed. As hippos will often engage in raiding nearby crops if the opportunity arises, humans may also come in conflict with them on these occasions, with potential for fatalities on both sides.


In zoos

Hippos have long been popular zoo animals. The first record of hippos on captivity for display are dated to 3500 BC, in Hierakonpolis, Egypt. The first zoo hippo in modern history was Obaysch, who arrived at the
London Zoo London Zoo is the world's oldest scientific zoo A zoo (short for zoological garden; also called an animal park or menagerie) is a facility in which animal Animals (also called Metazoa) are multicellular eukaryotic organisms that form ...
on 25 May 1850, where he attracted up to 10,000 visitors a day and inspired a popular song, the "Hippopotamus Polka". Hippos generally breed well in captivity; birth rates are lower than in the wild, but this is attributed to zoos wanting to limit births, since hippos are relatively expensive 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 grass. In the 1980s, zoo exhibits increasingly reflected native habitats. For example, the Toledo Zoo Hippoquarium features a pool. In 1987, the Toledo Zoo saw the first underwater birth by a captive hippo. The exhibit was so popular, the hippos became the logo of the Toledo Zoo.


Cultural depictions

A red hippo represented the
Ancient Egyptian god Ancient Egyptian deities are the gods A deity or god is a supernatural The supernatural encompasses supposed phenomena or entities that are not subject to the . This term is attributed to , such as s, s, , and . It also includes claim ...
Set; the thigh is the "
phallic A phallus is a penis (especially when Erection, erect), an object that resembles a penis, or a mimesis, mimetic image of an erect penis. In art history a figure with an erect penis is described as ithyphallic. Any object that symbolically— ...
leg of Set", symbolising virility. Set's consort
Tawaret In Ancient Egyptian religion, Taweret (also spelled Taurt, Tuat, Tuart, Ta-weret, Tawaret, Twert and Taueret, and in Greek language, Greek, Θουέρις – Thouéris, Thoeris, Taouris and Toeris) is the protective ancient Egyptian deities, anc ...

Tawaret
was also seen as part hippo and was a goddess of protection in pregnancy and childbirth, because ancient Egyptians recognised the protective nature of a female hippo toward her young. The
Ijaw people Ijaw people are a mixture of people majorly a tribe in Bayelsa in South South region in Niger Delta Image:NigerDeltaStates.png, 375px, Map of Nigeria numerically showing states typically considered part of the Niger Delta region: 1. Abia State, ...
of the
Niger Delta The Niger Delta is the delta Delta commonly refers to: * Delta (letter) (Δ or δ), a letter of the Greek alphabet * River delta, a landform at the mouth of a river * D (NATO phonetic alphabet: "Delta"), the fourth letter of the modern English ...
wore masks of aquatic animals like the hippo when practicing their
water spirit A water spirit is a kind of supernatural being found in the folklore of many cultures: African Some water spirits in traditional African religion include: * Mami Wata is a transcultural Pantheon (gods), pantheon of water spirits and deities of ...
cults and hippo ivory was used in the
divination Divination (from Latin ''divinare'', 'to foresee, to foretell, to predict, to prophesy') is the attempt to gain insight into a question or situation by way of an occult The occult, in the broadest sense, is a category of supernatural ...

divination
rituals of the Yoruba. The
Behemoth Behemoth (; he, בהמות, ''behemot'') is a beast from the biblical Book of Job The Book of Job (; he, אִיּוֹב – ''ʾIyyōḇ'') is a book of the Hebrew Bible. It addresses the problem of theodicy, meaning why God permi ...

Behemoth
from the
Book of Job The Book of Job (; he, אִיּוֹב – ''ʾIyyōḇ'') is a book of the Hebrew Bible. It addresses the problem of theodicy, meaning why God permits evil in the world, through the experiences of the eponymous protagonist. Job (biblic ...
, 40:15–24 is thought to be based on a hippo. Hippos have been the subjects of various African folktales. According to a story, when the Creator assigned each animal its 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 that it can be inspected for fish bones. 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. Ever since Obaysch inspired the "Hippopotamus Polka", hippos have been popular animals in
Western culture Western culture, also known as Western civilization, Occidental culture, or Western society, is the heritage Heritage may refer to: History and society * In history History (from Greek , ''historia'', meaning "inquiry; knowledge acquired ...
for their rotund appearance that many consider comical. Stories of hippos such as Huberta, which became a celebrity in
South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. With over 60 million people, it is the world's 23rd-most populous nation and covers an area of . South Africa has three capital citie ...

South Africa
in the 1930s for trekking across the country; or the tale of Owen and Mzee, a hippo and tortoise which developed an intimate bond; have amused people who have bought hippo books, merchandise, and many stuffed hippo toys. 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. They 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 List of fictional pachyderms, popular cartoon characters, where their rotund frames are used for humorous effect. For example, the The Walt Disney Company, Disney film ''Fantasia (1940 film), Fantasia'' featured a ballerina hippo dancing to the opera ''La Gioconda (opera), La Gioconda'', Hanna-Barbera created Peter Potamus. and the ''Madagascar (franchise), Madagascar'' films feature a hippo named List of Madagascar (franchise) characters#Gloria, Gloria. The "Kinder Happy Hippo, Happy Hippos" characters were created in 1987 by the French designer André Roche to be hidden in the "Kinder Surprise egg" of the Italian chocolate company Ferrero SpA.


See also

* Armley Hippo


References


External links

* * * {{Authority control Hippopotamuses, Mammals of Africa Fauna of Sub-Saharan Africa Herbivorous mammals Vulnerable animals Vulnerable biota of Africa Mammals described in 1758 Articles containing video clips Taxa named by Carl Linnaeus Semiaquatic mammals