Cypriot pygmy hippopotamus Temporal range: Pleistocene to Early Holocene, | |
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Composite mounted skeleton of H. minor | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Artiodactyla |
Family: | Hippopotamidae |
Genus: | Hippopotamus |
Species: | †H. minor |
Binomial name | |
†Hippopotamus minor | |
Synonyms | |
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The Cypriot pygmy hippopotamus (Hippopotamus minor or Phanourios minor) is an extinct species of dwarf hippopotamus that inhabited the island of Cyprus from the Pleistocene until the early Holocene. One the smallest known hippopotamus species, it was comparable in size to the living pygmy hippopotamus though it was more closely related to the common hippopotamus, with its small body size a result of insular dwarfism. It represented one of only two large terrestrial mammals on Cyprus alongside the Cyprus dwarf elephant. The species became extinct around 12,000 years ago following the arrival of humans on Cyprus, and potential evidence of human hunting has been found at the Aetokremnos rockshelter on the southern coast of the island.
Bones of fossil mammals have been known on Cyprus since at least the 15th century, when Cypriot historian Leontios Machairas reported that bones exposed in the Kyrenia/Pentadactylos mountains in the northern part of Cyprus were believed by locals to be the bones of Maronite Christians who had fled to the island, which they regarded as saints. An account from a later historian, Benedetto Bordone published in 1528, reporting on a similar deposit in the Kyrenia mountains, recounted that locals ground the bones into powder to make a potion they thought could cure many diseases. In 1698, the Dutch traveller Cornelis de Bruijn, remarking on another Kyrenia mountains bone deposit, made several images of bones he found, which he thought were deposited by the Biblical great flood. The remains in one of these images, which he identified as human, is now retrospectively identified as remains of the Cypriot pygmy hippopotamus. [2]
The earliest scientific description of the species was given by French paleontologist Anselme Gaëtan Desmarest in 1822, who gave the current name Hippopotamus minor. The species Hippopotamus minutus named shortly after by Georges Cuvier in 1824 is now regarded as a junior synonym. [3] Both authors were unaware of the origin of the specimens which were in the collections of a French museum in Paris, with Desmarest and Cuvier both suggesting that the specimens originated from southern France. Additional remains of the species were collected from Cyprus by British paleontologist Dorothea Bate in 1901, which led Charles Immanuel Forsyth Major to recognise material in the Paris collection as also originating from Cyprus. [4] The species is now known from over 20 localities across the island. [5] In 1972, the species was placed in the new genus Phanourios by Paul Yves Sondaar and Gijsbert Jan Boekschoten after Saint Phanourios which local Cypriots associated with its bones. [6] However this placement has been questioned due to the fact that it is widely agreed that the species descends from a species of the genus Hippopotamus, and other authors have continued to use the combination Hippopotamus minor. [7] [8]
A partial mitochondrial genome obtained from H. minor suggests that its closest living relative is the common hippopotamus (Hippopotamus amphibius), with an estimated genetic divergence between 1.36 to 1.58 million years ago. [7] The ancestor of the Cypriot pygmy hippopotamus is uncertain, but is likely either H. amphibius [7] or the extinct species Hippopotamus antiquus . [9] The timing of the colonisation is uncertain, though the earliest fossils date to around 219-185,000 years ago, during the late Middle Pleistocene. [7] Due to Cyprus never having been connected to the mainland, its ancestors must have arrived via crossing the Mediterranean, perhaps as the result of a rare cataclysmic flooding event. [10] Its small body size is due to insular dwarfism, a common phenomenon on islands. [7]
The Cypriot pygmy hippopotamus is the smallest known hippopotamus species, along with the roughly same-sized living African pygmy hippopotamus (Choeropsis liberiensis). The Cypriot pygmy hippopotamus is estimated to have had a body mass of around 130 kilograms (290 lb), [7] a height of 70 cm (2.3 ft) and a length of 125 cm (4.1 ft), [2] an over 90% reduction in size from its mainland ancestor. [8] The cranial cavity containing the brain is proportionally significantly larger relative to skull size than in H. amphibius. [11] Compared to H. amphibius, the muzzle region of the skull is much shorter, resmbling the condition found in the African pygmy hippopotamus. [8] Unlike other species of the genus Hippopotamus, the upper fourth premolar has been lost, possibly as a result of the skull shortening. [8] The teeth of H. minor are more brachydont (less high crowned) than those of H. amphibius, suggesting that H. minor probably occupied a browsing niche, in contrast to the grazing predominant diet of modern Hippopotamus amphibius, though its diet is likely to have varied in correspondence to glacial cycle-induced climatic changes. [12] Analysis of the limb and hand bones suggests that it was more terrestrial than its living relatives, having a unique form of locomotion distinct from modern hippopotamuses that allowed it to move efficiently on the mountainous and rocky terrain of Cyprus, with changes including the shortening of the distal (closest to foot) part of the legs, and increased robustness of the limb bones, as well as increased rigidity and stability of some of the limb joints. [13] [9] It probably habitually moved slowly, moreso than living hippopotamuses, [13] and was probably incapable of running quickly. [2]
During the Late Pleistocene, the Cypriot pygmy hippopotamus, along with the similarly sized Cyprus dwarf elephant, were the only large mammals native to the islands, and one of only four native terrestrial mammal species, alongside the still living Cypriot mouse and the extinct genet species Genetta plesictoides, [14] and had no natural predators. [15] Remains of the dwarf hippopotamus are abundant at localities where it is found, considerably moreso than the dwarf elephant. [5]
The youngest remains of the species date to the end of the Pleistocene, around 13-12,000 years ago, around the same time as the youngest remains of the dwarf elephant species. These dates roughly coincide with the oldest evidence of human habitation of Cyprus. [16] Over 200,000 bones of H. minor, representing over 500 individuals, are associated with human artifacts at the Aetokremnos rockshelter on the southern coast of Cyprus, dating to approximately 13-12,000 years Before Present, representing among the youngest records of the species, which is suggested by some authors to provide evidence that the Cypriot pygmy hippopotamus was hunted and driven to extinction by the early human residents of Cyprus. [17] [18] [19] [20] However, these suggestions have been contested, in part due to a lack of cut marks on the bones that would definitively indicate butchery, with an alternative proposal that bones at Aetokremnos accumulated naturally over hundreds of years, with the human occupation of the site after the bones were initially deposited. [16] [21]
A 2024 study estimated that at the time of human arrival, the population of dwarf hippopotamus on Cyprus was around 14,300 individuals. The study suggested that harvesting over 650 dwarf hippos per year would have put the species at risk of extinction, with extinction becoming nearly certain with over 1000 individuals harvested per year (realistically accomplishable with a human population of only a few thousand people likely present on Cyprus during this time). This likely would have resulted in a relatively rapid extinction following the colonisation at Cyprus, with the auther estimating a latest possible extinction date (taking into account the Signor-Lipps effect) of around 12,000-11,000 years ago. [22]
The hippopotamus (; pl.: hippopotamuses; also shortened to hippo, further qualified as the common hippopotamus, Nile hippopotamus, or river hippopotamus, is a large semiaquatic mammal native to sub-Saharan Africa. It is one of only two extant species in the family Hippopotamidae, the other being the pygmy hippopotamus. Its name comes from the ancient Greek for "river horse".
Hippopotamidae is a family of stout, naked-skinned, and semiaquatic artiodactyl mammals, possessing three-chambered stomachs and walking on four toes on each foot. While they resemble pigs physiologically, their closest living relatives are the cetaceans. They are sometimes referred to as hippopotamids.
The pygmy hippopotamus or pygmy hippo is a small hippopotamid which is native to the forests and swamps of West Africa, primarily in Liberia, with small populations in Sierra Leone, Guinea, and Ivory Coast. It has been extirpated from Nigeria.
Aetokremnos is a rock shelter near Limassol on the southern coast of Cyprus. It is widely considered to host some of the oldest evidence of human habitation of Cyprus, dating to around 12,000 years ago. It is situated on a steep cliff site c. 40 m (131.23 ft) above the Mediterranean sea. The name means "Cliff of the eagles" in Greek. Around 40 m2 (430.56 sq ft) have been excavated and out of the four layers documented, the third is sterile.
Palaeoloxodon is an extinct genus of elephant. The genus originated in Africa during the Early Pleistocene, and expanded into Eurasia at the beginning of the Middle Pleistocene. The genus contains the largest known species of elephants, over 4 metres (13 ft) tall at the shoulders and over 13 tonnes (29,000 lb) in weight, representing among the largest land mammals ever, including the African Palaeoloxodon recki, the European straight-tusked elephant and the South Asian Palaeoloxodon namadicus. P. namadicus has been suggested to be the largest known land mammal by some authors based on extrapolation from fragmentary remains, though these estimates are highly speculative. In contrast, the genus also contains many species of dwarf elephants that evolved via insular dwarfism on islands in the Mediterranean, some like Palaeoloxodon falconeri less than 1 metre (3.3 ft) in shoulder height as fully grown adults, making them the smallest elephants known. The genus has a long and complex taxonomic history, and at various times, it has been considered to belong to Loxodonta or Elephas, but today is usually considered a valid and separate genus in its own right.
Dwarf elephants are prehistoric members of the order Proboscidea which, through the process of allopatric speciation on islands, evolved much smaller body sizes in comparison with their immediate ancestors. Dwarf elephants are an example of insular dwarfism, the phenomenon whereby large terrestrial vertebrates that colonize islands evolve dwarf forms, a phenomenon attributed to adaptation to resource-poor environments and lack of predation and competition.
Hippopotamus is a genus of artiodactyl mammals consisting of one extant species, Hippopotamus amphibius, the river hippopotamus, and several extinct species from both recent and prehistoric times. It belongs to the family Hippopotamidae, which also includes the pygmy hippopotamus and a number of extinct genera.
Palaeoloxodon falconeri is an extinct species of dwarf elephant from the Middle Pleistocene of Sicily and Malta. It is amongst the smallest of all dwarf elephants at under 1 metre (3.3 ft) in height. A member of the genus Palaeoloxodon, it derived from a population of the mainland European straight-tusked elephant.
The Cypriot mouse is a species of mouse endemic to Cyprus. Its primary habitat seems to be the vineyards and fields of the Troödos Mountains region.
Whippomorpha or Cetancodonta is a group of artiodactyls that contains all living cetaceans and hippopotamuses. All whippomorphs are descendants of the last common ancestor of Hippopotamus amphibius and Tursiops truncatus. This makes it a crown group. Whippomorpha is a suborder within the order Artiodactyla. The placement of Whippomorpha within Artiodactyla is a matter of some contention, as hippopotamuses were previously considered to be more closely related to Suidae (pigs) and Tayassuidae (peccaries). Most contemporary scientific phylogenetic and morphological research studies link hippopotamuses with cetaceans, and genetic evidence has overwhelmingly supported an evolutionary relationship between Hippopotamidae and Cetacea. Modern whippomorphs all share a number of behavioural and physiological traits; such as a dense layer of subcutaneous fat and largely hairless bodies. They exhibit amphibious and aquatic behaviors and possess similar auditory structures.
Hippopotamus antiquus is an extinct species of the genus Hippopotamus that ranged across Europe during the Early and Middle Pleistocene. It was considerably larger than the living hippopotamus.
Hippopotamus pentlandi is an extinct species of hippopotamus from Sicily, known from the late Middle Pleistocene to early Late Pleistocene. It is the largest of the insular dwarf hippos known from the Pleistocene of the Mediterranean, "at most 20% smaller than the mainland forms", with an estimated body mass of approximately 1100 kg. It is suggested that it arrived in Sicily between 250,000 and 150,000 years ago, probably descending from the modern hippopotamus, with an origin from Hippopotamus antiquus being less likely. In comparison to those species, the muzzle was shorter, the occipital and nasal regions were more developed, the mastoid process was enlarged, and the dental row was shortened, and the condyle of the mandible is low. In comparison to H. amphibius, the orbits are also elevated. It was present in Sicily until at least the latest Middle Pleistocene around 120 kya, and was probably extinct by the beginning of Marine Isotope Stage 4. Contemporaneous species include the dwarf elephant Palaeoloxodon mnaidriensis, the aurochs, red deer, steppe bison, fallow deer, wild boar, brown bear, wolves, red foxes, cave hyena and cave lions. Its diet was likely grazing dominated, similar to that of modern H. amphibius. It is probably ancestral to Hippopotamus melitensis from Malta, which is substantially smaller than H. pentlandi.
Lemerle's dwarf hippopotamus is an extinct species of Malagasy hippopotamus.
Several species of Malagasy hippopotamus lived on the island of Madagascar but are now believed to be extinct. The animals were very similar to the extant hippopotamus and pygmy hippopotamus. The fossil record suggests that at least one species of hippopotamus lived until about 1,000 years ago and other evidence suggests that the species may have survived until much more recently. The taxonomy of these animals is not resolved and not widely studied.
Palaeoloxodon cypriotes is an extinct species of dwarf elephant that inhabited the island of Cyprus during the Late Pleistocene. A probable descendant of the large straight-tusked elephant of mainland Europe and West Asia, the species is among the smallest known dwarf elephants, with fully grown individuals having an estimated shoulder height of only 1 metre (3.3 ft). It represented only one of two large animal species on the island alongside the Cypriot pygmy hippopotamus. The species became extinct around 12,000 years ago, around the time humans first colonised Cyprus, and potential evidence of human hunting has been found.
Hippopotamus creutzburgi, the Cretan dwarf hippopotamus, is an extinct species of hippopotamus from the island of Crete. It lived on the island from the Early Pleistocene to early Middle Pleistocene, and probably descended from Hippopotamus antiquus. It was considerably smaller than H. antiquus, weighing approximately 400 kilograms (880 lb), an example of insular dwarfism. It was one of only two large herbivores on the island during its existence, alongside the dwarf mammoth Mammuthus creticus, with large predators being absent, the only other species of mammal present on the island being the giant rat Kritimys. It is known from abundant remains collected from the Katharo basin in the eastern uplands of Crete, approximately 1,100–1,200 metres (3,600–3,900 ft) above sea level, as well as much rarer remains found in coastal caves. Analysis of its limbs suggests that it was more adapted to terrestrial locomotion than living hippopotamus, primarily walking on its hooves rather than its footpads as in living hippopotamus, and capable of traversing the rugged terrain of Crete. Analysis of its teeth suggests that it had a grazing diet, similar to modern Hippopotamus amphibius. The previous suggestion that the species can be divided into two subspecies is not supported by modern research.
Palaeoloxodon mnaidriensis is an extinct species of dwarf elephant belonging to the genus Palaeoloxodon, native to the Siculo-Maltese archipelago during the late Middle Pleistocene and Late Pleistocene. It is derived from the European mainland straight-tusked elephant.
Hippopotamus laloumena is an extinct species of hippopotamus from Pleistocene and Holocene Madagascar, making it the oldest of Malagasy hippopotamus. H. laloumena was much larger than other Malagasy hippopotamus, but was still somewhat smaller than the common hippopotamus. However, little is known about the species because it was identified with only a lower jaw and limb bones. It was described in 1990 by French palaeontologists M. Faure and Guerin, the fossils recovered from a site near Mananjary on the east coast of Madagascar. The species name derives from Malagasy laloumena "hippopotamus".
Mammuthus creticus, or the Cretan dwarf mammoth, is an extinct species of dwarf mammoth endemic to Crete during the Early Pleistocene to early Middle Pleistocene.
Kritimys, also known as the Cretan giant rat is an extinct genus of murid rodent that was endemic to the island of Crete during the Early and Middle Pleistocene. There are two known species, K. kiridus from the Early-Mid Pleistocene, and its descendant K. catreus from the Middle Pleistocene. It is suggested to be closely related to and probably derived from Praomys. As with most island rodents, Kritimys was larger than its mainland relatives, with its size increasing over time, with K. catreus estimated to weigh 518 grams (1.142 lb), around 6.7 times the weight of its mainland ancestor, an example of island gigantism. The temporal range of the genus is considered to define the regional Kritimys biozone, during which time there were only two other species of mammal native to the island, a species of dwarf mammoth, Mammuthus creticus and the dwarf hippopotamus Hippopotamus creutzburgi. It became extinct during the late Middle Pleistocene, following the arrival of the Mus bateae-minotaurus lineage to the island, exhibiting a decrease in size shortly before its extinction.