HOME

TheInfoList



OR:

The wild horse (''Equus ferus'') is a
species In biology, a species is the basic unit of 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 individuals of the appropriate s ...
of the
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''Equus'', which includes as
subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
the modern
domesticated Domestication is a sustained multi-generational relationship in which humans assume a significant degree of control over the reproduction and care of another group of organisms to secure a more predictable supply of resources from that group. A ...
horse The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million y ...
(''Equus ferus caballus'') as well as the
endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...
Przewalski's horse Przewalski's horse (, , (Пржевальский ), ) (''Equus ferus przewalskii'' or ''Equus przewalskii''), also called the takhi, Mongolian wild horse or Dzungarian horse, is a rare and endangered horse originally native to the steppes of Ce ...
(''Equus ferus przewalskii''). The European wild horse known as the
tarpan The term tarpan (''Equus ferus ferus'') refers to free-ranging horses of the Russian steppe from the 18th to the 20th century. It is generally unknown whether those horses represented genuine wild horses, feral domestic horses or hybrids. The las ...
that went extinct in the late 1800s has previously been classified as a subspecies of wild horse (''Equus ferus ferus''), but more recent studies have cast doubt on whether those horses were truly wild or if they actually were
feral horse A feral horse is a free-roaming horse of domesticated stock. As such, a feral horse is not a wild animal in the sense of an animal without domesticated ancestors. However, some populations of feral horses are managed as wildlife, and these ...
s or hybrids.Tadeusz Jezierski, Zbigniew Jaworski: ''Das Polnische Konik. Die Neue Brehm-Bücherei Bd. 658'', Westarp Wissenschaften, Hohenwarsleben 2008, Przewalski's horse had reached the brink of
extinction Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
but was reintroduced successfully into the wild. The tarpan became extinct in the 19th century but is theorized to have been present on the
steppe In physical geography, a steppe () is an ecoregion characterized by grassland plains without trees apart from those near rivers and lakes. Steppe biomes may include: * the montane grasslands and shrublands biome * the temperate grasslands, ...
s of
Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...
at the time of domestication. However, other subspecies of ''Equus ferus'' may have existed and could have been the stock from which domesticated horses are descended. Since the extinction of the tarpan, attempts have been made to reconstruct its
phenotype In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological proper ...
using domestic horses, resulting in
horse breeds This article is a list of horse and pony breeds with articles on Wikipedia, and also includes terms for types of horse that are not necessarily standardized breeds but are often labeled as breeds. While there is no scientifically accepted defini ...
such as the
Heck horse The Heck horse is a horse breed that is claimed to resemble the tarpan (''Equus ferus ferus''), an extinct equine. The breed was created by the German zoologist brothers Heinz Heck and Lutz Heck in an attempt to breed back the tarpan. Al ...
. However, the genetic makeup and
foundation bloodstock Foundation bloodstock or foundation stock refers to animals that are the progenitors, or foundation, of a breed or of a given bloodline within such. Many modern breeds can be traced to specific, named foundation animals, but a group of animals m ...
of those breeds is substantially derived from domesticated horses, so these breeds possess domesticated traits. The term "wild horse" is also used
colloquially Colloquialism (), also called colloquial language, everyday language or general parlance, is the style (sociolinguistics), linguistic style used for casual (informal) communication. It is the most common functional style of speech, the idiom norm ...
in reference to free-roaming herds of
feral horse A feral horse is a free-roaming horse of domesticated stock. As such, a feral horse is not a wild animal in the sense of an animal without domesticated ancestors. However, some populations of feral horses are managed as wildlife, and these ...
s, for example the
mustang The mustang is a free-roaming horse of the Western United States, descended from horses brought to the Americas by the Spanish. Mustangs are often referred to as wild horses, but because they are descended from once-domesticated animals, they ...
in the United States, and the
brumby A brumby is a free-roaming feral horse in Australia. Although found in many areas around the country, the best-known brumbies are found in the Australian Alps region. Today, most of them are found in the Northern Territory, with the second ...
in Australia. These feral horses are untamed members of the domestic horse subspecies (''Equus ferus caballus''), not to be confused with the truly "wild" horse subspecies extant into modern times.


Distribution

Evidence supports ''E. ferus'' as having evolved in
North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
about 1.1 - 1.2
million years ago The abbreviation Myr, "million years", is a unit of a quantity of (i.e. ) years, or 31.556926 teraseconds. Usage Myr (million years) is in common use in fields such as Earth science and cosmology. Myr is also used with Mya (million years ago). ...
. Around 800,000 - 900,000 years ago, ''E. ferus'' migrated west to
Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...
via the
Bering Land Bridge Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72 degrees north latitude in the Chukchi Sea; and on the south by the tip of ...
, and south to
South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
via the
Isthmus of Panama The Isthmus of Panama ( es, Istmo de Panamá), also historically known as the Isthmus of Darien (), is the narrow strip of land that lies between the Caribbean Sea and the Pacific Ocean, linking North and South America. It contains the country ...
as part of the
Great American Interchange The Great American Biotic Interchange (commonly abbreviated as GABI), also known as the Great American Interchange and the Great American Faunal Interchange, was an important late Cenozoic paleozoogeographic biotic interchange event in which lan ...
. By the mid-late
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 was fina ...
, it had an extremely large range across the Americas, Eurasia, and North Africa, across which it was abundant. There have been several fossil horse taxa from throughout this range, such as ''
Equus lambei ''Equus lambei'', commonly known as the Yukon horse or Yukon wild horse, is an extinct species of the genus '' Equus''. ''Equus lambei'' ranged across North America until approximately 10,000 years ago. Based on recent examinations of the m ...
'' and ''
Amerhippus ''Amerhippus'' is an extinct South American horse of uncertain taxonomic identity. It is sometimes classified as a subgenus of the genus '' Equus'', containing several extinct species of horses that lived in South America, or a single, morphologi ...
'', that were formerly considered distinct species, but genetic and morphological analysis supports them as being
conspecific 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 organ ...
with ''E. ferus''. By the latest Pleistocene or early
Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togethe ...
, American populations had disappeared as part of the
Quaternary extinction event The Quaternary period (from 2.588 ± 0.005 million years ago to the present) has seen the extinctions of numerous predominantly megafaunal species, which have resulted in a collapse in faunal density and diversity and the extinction of key ecolog ...
, leaving only the
Old World The "Old World" is a term for Afro-Eurasia that originated in Europe , after Europeans became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia, which were previously thought of by the ...
populations. It remained widespread there and was ultimately also
domesticated Domestication is a sustained multi-generational relationship in which humans assume a significant degree of control over the reproduction and care of another group of organisms to secure a more predictable supply of resources from that group. A ...
around 3600 B.C., but wild populations continued to decline. The last completely wild populations of the
tarpan The term tarpan (''Equus ferus ferus'') refers to free-ranging horses of the Russian steppe from the 18th to the 20th century. It is generally unknown whether those horses represented genuine wild horses, feral domestic horses or hybrids. The las ...
went extinct in
Eastern Europe Eastern Europe is a subregion of the Europe, European continent. As a largely ambiguous term, it has a wide range of geopolitical, geographical, ethnic, cultural, and socio-economic connotations. The vast majority of the region is covered by Russ ...
and the southern parts of
Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...
around the late 19th century, and the
Przewalski's horse Przewalski's horse (, , (Пржевальский ), ) (''Equus ferus przewalskii'' or ''Equus przewalskii''), also called the takhi, Mongolian wild horse or Dzungarian horse, is a rare and endangered horse originally native to the steppes of Ce ...
of
Central Asia Central Asia, also known as Middle Asia, is a subregion, region of Asia that stretches from the Caspian Sea in the west to western China and Mongolia in the east, and from Afghanistan and Iran in the south to Russia in the north. It includes t ...
became
extinct in the wild A species that is extinct in the wild (EW) is one that has been categorized by the International Union for Conservation of Nature as known only by living members kept in captivity or as a naturalized population outside its historic range due ...
in 1969. However, over the past few centuries
feral horse A feral horse is a free-roaming horse of domesticated stock. As such, a feral horse is not a wild animal in the sense of an animal without domesticated ancestors. However, some populations of feral horses are managed as wildlife, and these ...
s have been introduced to all continents except
Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...
, and Przewalski's horses have been
reintroduced Species reintroduction is the deliberate release of a species into the wild, from captivity or other areas where the organism is capable of survival. The goal of species reintroduction is to establish a healthy, genetically diverse, self-sustainin ...
to their former habitats in Mongolia.


Ecology

In general, wild horses are
grazer Grazer may refer to: *grazer, an animal that grazes *Grazer, a native or inhabitant of Graz *GRAZER, the shoegaze band GRAZER Astronomy * Earth Grazer, Earth-grazing fireball that enters the Earth's atmosphere and leaves again * Mercury grazer, ...
s that prefer to inhabit open areas, such as
steppes In physical geography, a steppe () is an ecoregion characterized by grassland plains without trees apart from those near rivers and lakes. Steppe biomes may include: * the montane grasslands and shrublands biome * the temperate grasslands, ...
and
grassland A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
s. They may have seasonal food preferences, as seen in the Przewalski's subspecies. Horses may fall prey to native predators where they live, such as
wolves The wolf (''Canis lupus''; plural, : wolves), also known as the gray wolf or grey wolf, is a large Canis, canine native to Eurasia and North America. More than thirty subspecies of Canis lupus, subspecies of ''Canis lupus'' have been reco ...
,
cougar The cougar (''Puma concolor'') is a large Felidae, cat native to the Americas. Its Species distribution, range spans from the Canadian Yukon to the southern Andes in South America and is the most widespread of any large wild terrestrial mamm ...
s, and
spotted hyena The spotted hyena (''Crocuta crocuta''), also known as the laughing hyena, is a hyena species, currently classed as the sole extant member of the genus ''Crocuta'', native to sub-Saharan Africa. It is listed as being of least concern by the IUC ...
s.


Subspecies and their history

''E. ferus'' has had several subspecies, only three of which have survived into modern times: *The
domestic horse The horse (''Equus ferus caballus'') is a Domestication, domesticated, odd-toed ungulate, one-toed, ungulate, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two Extant taxon, extant subspecies of wild horse, ''Equus fer ...
(''Equus ferus caballus''). *The Eurasian wild horse (''Equus ferus ferus''); originally considered synonymous with the tarpan, though recent research has cast doubt on this. The tarpan was once native to Europe and
western Asia Western Asia, West Asia, or Southwest Asia, is the westernmost subregion of the larger geographical region of Asia, as defined by some academics, UN bodies and other institutions. It is almost entirely a part of the Middle East, and includes Ana ...
before it became effectively extinct in the late 19th century. The last specimen died in 1909 whilst in captivity in an estate in
Poltava Governorate The Poltava Governorate (russian: Полтавская губерния, Poltavskaya guberniya; ua, Полтавська Губернія, translit=Poltavska huberniia) or Poltavshchyna was a Governorate (Russia), gubernia (also called a provin ...
,
Russian Empire The Russian Empire was an empire and the final period of the Russian monarchy from 1721 to 1917, ruling across large parts of Eurasia. It succeeded the Tsardom of Russia following the Treaty of Nystad, which ended the Great Northern War. ...
. *
Przewalski's horse Przewalski's horse (, , (Пржевальский ), ) (''Equus ferus przewalskii'' or ''Equus przewalskii''), also called the takhi, Mongolian wild horse or Dzungarian horse, is a rare and endangered horse originally native to the steppes of Ce ...
(''Equus ferus przewalskii''); also known as the Mongolian wild horse or takhi, it is native to
Central Asia Central Asia, also known as Middle Asia, is a subregion, region of Asia that stretches from the Caspian Sea in the west to western China and Mongolia in the east, and from Afghanistan and Iran in the south to Russia in the north. It includes t ...
and the
Gobi Desert The Gobi Desert (Chinese: 戈壁 (沙漠), Mongolian: Говь (ᠭᠣᠪᠢ)) () is a large desert or brushland region in East Asia, and is the sixth largest desert in the world. Geography The Gobi measures from southwest to northeast an ...
. The latter two are the only never-domesticated "wild" groups that survived into historic times. However, other subspecies of ''Equus ferus'' may have existed.Colin Groves, 1986, "The taxonomy, distribution, and adaptations of recent Equids", In Richard H. Meadow and Hans-Peter Uerpmann, eds., ''Equids in the Ancient World, volume I,'' pp. 11-65, Wiesbaden: Ludwig Reichert Verlag. In the
Late Pleistocene The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth division of ...
epoch, there were several other subspecies of ''E.ferus'' which have all since gone
extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
. The exact categorization of ''Equus remains into species or subspecies is a complex matter and the subject of ongoing work.


Evolutionary history and taxonomy

The horse family
Equidae Equidae (sometimes known as the horse family) is the taxonomic family of horses and related animals, including the extant horses, asses, and zebras, and many other species known only from fossils. All extant species are in the genus '' Equus'', ...
and the genus ''Equus'' evolved in North America during the
Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Beringia Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72 degrees north latitude in the Chukchi Sea; and on the south by the tip ...
into the
Eastern Hemisphere The Eastern Hemisphere is the half of the planet Earth which is east of the prime meridian (which crosses Greenwich, London, United Kingdom) and west of the antimeridian (which crosses the Pacific Ocean and relatively little land from pole to pol ...
. Studies using
ancient DNA Ancient DNA (aDNA) is DNA isolated from ancient specimens. Due to degradation processes (including cross-linking, deamination and fragmentation) ancient DNA is more degraded in comparison with contemporary genetic material. Even under the bes ...
, as well as DNA of recent individuals, suggest the presence of two equine species in Late Pleistocene North America, a caballine species, suggested to be conspecific with the wild horse, and '' Haringtonhippus francisci'', the "New World stilt-legged horse"; the latter has been
taxonomically In biology, taxonomy () is the scientific study of naming, defining ( circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxa (singular: taxon) and these groups are given ...
assigned to various names, and appears to be outside the grouping containing all extant equines. In South America there appear to have been several species of equine, ''Equus'' (''
Amerhippus ''Amerhippus'' is an extinct South American horse of uncertain taxonomic identity. It is sometimes classified as a subgenus of the genus '' Equus'', containing several extinct species of horses that lived in South America, or a single, morphologi ...
'') ''neogeus,'' which had previously thought to represent 5 taxa due to morphological variability, and several species of ''
Hippidion ''Hippidion'' (meaning ''little horse'') is an extinct genus of equine that lived in South America from the Late Pliocene to the end of the Late Pleistocene ( Lujanian), between two million and 11,000 years ago. They were one of two lineages of e ...
,'' which also lie outside the group containing all living horses. (It had previously been suggested to have been nested within ''Equus'' based on incomplete sequence data) Currently, three subspecies that lived during recorded human history are recognized. One subspecies is the widespread
domestic horse The horse (''Equus ferus caballus'') is a Domestication, domesticated, odd-toed ungulate, one-toed, ungulate, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two Extant taxon, extant subspecies of wild horse, ''Equus fer ...
(''Equus ferus caballus''), as well as two wild subspecies: the recently extinct European wild horse (''E. f. ferus'') and the endangered
Przewalski's horse Przewalski's horse (, , (Пржевальский ), ) (''Equus ferus przewalskii'' or ''Equus przewalskii''), also called the takhi, Mongolian wild horse or Dzungarian horse, is a rare and endangered horse originally native to the steppes of Ce ...
(''E. f. przewalskii''). Genetically, the pre-domestication horse, ''E. f. ferus'', and the domesticated horse, ''E. f. caballus'', form a single homogeneous group (
clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...
) and are genetically indistinguishable from each other. The genetic variation within this clade shows only a limited regional variation, with the notable exception of Przewalski's horse. Przewalski's horse has several unique genetic differences that distinguish it from the other subspecies, including 66 instead of 64
chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...
s, unique
Y-chromosome The Y chromosome is one of two sex chromosomes (allosomes) in therian mammals, including humans, and many other animals. The other is the X chromosome. Y is normally the sex-determining chromosome in many species, since it is the presence or abs ...
gene
haplotype A haplotype ( haploid genotype) is a group of alleles in an organism that are inherited together from a single parent. Many organisms contain genetic material ( DNA) which is inherited from two parents. Normally these organisms have their DNA or ...
s, and unique
mtDNA Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial DNA ...
haplotypes. Besides genetic differences,
osteological Osteology () is the scientific study of bones, practised by osteologists. A subdiscipline of anatomy, anthropology, and paleontology, osteology is the detailed study of the structure of bones, skeletal elements, teeth, microbone morphology, func ...
evidence from across the Eurasian wild horse range, based on cranial and metacarpal differences, indicates the presence of only two subspecies in postglacial times, the tarpan and Przewalski's horse.


Scientific naming of the species

At present, the domesticated and wild horses are considered a single species, with the valid scientific name for the horse species being ''Equus ferus.'' The wild tarpan subspecies is ''E. f. ferus'', Przewalski's horse is ''E. f. przewalskii'', and the domesticated horse is ''E. f. caballus''. The rules for the scientific naming of animal species are determined in the
International Code of Zoological Nomenclature The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its publisher, the ...
, which stipulates that the oldest available valid scientific name is used to name the species. Previously, when taxonomists considered domesticated and wild horse two subspecies of the same species, the valid scientific name was ''Equus caballus'' Linnaeus 1758, with the subspecies labeled ''E. c. caballus'' (domesticated horse), ''E. c. ferus'' Boddaert, 1785 (tarpan) and ''E. c. przewalskii'' Poliakov, 1881 (Przewalski's horse). However, in 2003, the
International Commission on Zoological Nomenclature The International Commission on Zoological Nomenclature (ICZN) is an organization dedicated to "achieving stability and sense in the scientific naming of animals". Founded in 1895, it currently comprises 26 commissioners from 20 countries. Orga ...
decided that the scientific names of the wild species have priority over the scientific names of domesticated species, therefore mandating the use of ''Equus ferus'' for the horse, independent of the position of the domesticated horse.


Przewalski's horse

Przewalski's horse Przewalski's horse (, , (Пржевальский ), ) (''Equus ferus przewalskii'' or ''Equus przewalskii''), also called the takhi, Mongolian wild horse or Dzungarian horse, is a rare and endangered horse originally native to the steppes of Ce ...
occupied the eastern
Eurasian Steppe The Eurasian Steppe, also simply called the Great Steppe or the steppes, is the vast steppe ecoregion of Eurasia in the temperate grasslands, savannas and shrublands biome. It stretches through Hungary, Bulgaria, Romania, Moldova and Transnistri ...
s, perhaps from the
Urals The Ural Mountains ( ; rus, Ура́льские го́ры, r=Uralskiye gory, p=ʊˈralʲskʲɪjə ˈɡorɨ; ba, Урал тауҙары) or simply the Urals, are a mountain range that runs approximately from north to south through European ...
to
Mongolia Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...
, although the ancient border between tarpan and Przewalski's distributions has not been clearly defined. Przewalski's horse was limited to
Dzungaria Dzungaria (; from the Mongolian language, Mongolian words , meaning 'left hand') is a geographical subregion in Northwest China that corresponds to the northern half of Xinjiang. It is thus also known as Beijiang, which means "Northern Xinjiang" ...
and western
Mongolia Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...
in the same period, and became
extinct in the wild A species that is extinct in the wild (EW) is one that has been categorized by the International Union for Conservation of Nature as known only by living members kept in captivity or as a naturalized population outside its historic range due ...
during the 1960s, but was reintroduced in the late 1980s to two preserves in
Mongolia Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...
. Although researchers such as
Marija Gimbutas Marija Gimbutas ( lt, Marija Gimbutienė, ; January 23, 1921 – February 2, 1994) was a Lithuanian archaeologist and anthropologist known for her research into the Neolithic and Bronze Age cultures of " Old Europe" and for her Kurgan hypothesis, ...
theorized that the horses of the
Chalcolithic The Copper Age, also called the Chalcolithic (; from grc-gre, χαλκός ''khalkós'', "copper" and  ''líthos'', "stone") or (A)eneolithic (from Latin '' aeneus'' "of copper"), is an archaeological period characterized by regular ...
period were Przewalski's, more recent genetic studies indicate that Przewalski's horse is not an ancestor to modern domesticated horses. In 2018, a DNA study revealed that the horses belonging to the
Botai culture The Botai culture is an archaeological culture (c. 3700–3100 BC) of prehistoric northern Central Asia. It was named after the settlement of Botai in today's northern Kazakhstan. The Botai culture has two other large sites: Krasnyi ...
were Przewalski's horses, raising the question of whether these animals were an isolated population, if extant Przewalski horses today represent feral descendants, or if the domestication attempt at Botai failed. A 2021 study argued that the Botai horses were most likely not domesticated, thus the question remains unresolved.William Timothy Treal Taylor and Christina Isabelle Barrón‑Ortiz: ''Rethinking the evidence for early horse domestication at Botai.'' Scientific Reports 11, 2021, S. 7440, doi:10.1038/s41598-021-86832-9 Przewalski's horse is still found today, though it is an
endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...
and for a time was considered extinct in the wild. Roughly 2000 Przewalski's horses are in
zoo A zoo (short for zoological garden; also called an animal park or menagerie) is a facility in which animals are kept within enclosures for public exhibition and often bred for conservation purposes. The term ''zoological garden'' refers to zoo ...
s around the world. A small breeding population has been reintroduced in Mongolia. As of 2005, a cooperative venture between the
Zoological Society of London The Zoological Society of London (ZSL) is a charity devoted to the worldwide conservation of animals and their habitats. It was founded in 1826. Since 1828, it has maintained the London Zoo, and since 1931 Whipsnade Park. History On 29 ...
and Mongolian scientists has resulted in a population of 248 animals in the wild. Przewalski's horse has some biological differences from the domestic
horse The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million y ...
; unlike
domesticated Domestication is a sustained multi-generational relationship in which humans assume a significant degree of control over the reproduction and care of another group of organisms to secure a more predictable supply of resources from that group. A ...
horses and the tarpan, which both have 64
chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...
s, Przewalski's horse has 66 chromosomes due to a
Robertsonian translocation Robertsonian translocation (ROB) is a chromosomal abnormality wherein a certain type of a chromosome becomes attached to another. It is the most common form of chromosomal translocation in humans, affecting 1 out of every 1,000 babies born. It doe ...
. However, the offspring of Przewalski and domestic horses are fertile, possessing 65 chromosomes.


Feral horses

Horses that live in an untamed state but have ancestors that have been
domesticated Domestication is a sustained multi-generational relationship in which humans assume a significant degree of control over the reproduction and care of another group of organisms to secure a more predictable supply of resources from that group. A ...
are called "feral horses". For instance, when the Spanish reintroduced the horse to the Americas, beginning in the late 15th century, some horses escaped, forming
feral A feral () animal or plant is one that lives in the wild but is descended from domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems and has, in some ...
herds; the best-known being the
mustang The mustang is a free-roaming horse of the Western United States, descended from horses brought to the Americas by the Spanish. Mustangs are often referred to as wild horses, but because they are descended from once-domesticated animals, they ...
. Similarly, the
brumby A brumby is a free-roaming feral horse in Australia. Although found in many areas around the country, the best-known brumbies are found in the Australian Alps region. Today, most of them are found in the Northern Territory, with the second ...
descended from horses strayed or let loose in Australia by English settlers. Isolated populations of
feral horse A feral horse is a free-roaming horse of domesticated stock. As such, a feral horse is not a wild animal in the sense of an animal without domesticated ancestors. However, some populations of feral horses are managed as wildlife, and these ...
s occur in a number of places, including
Bosnia Bosnia and Herzegovina ( sh, / , ), abbreviated BiH () or B&H, sometimes called Bosnia–Herzegovina and often known informally as Bosnia, is a country at the crossroads of south and southeast Europe, located in the Balkans. Bosnia and He ...
,
Croatia , image_flag = Flag of Croatia.svg , image_coat = Coat of arms of Croatia.svg , anthem = "Lijepa naša domovino"("Our Beautiful Homeland") , image_map = , map_caption = , capit ...
,
New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
,
Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...
,
Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the ...
and a number of
barrier island Barrier islands are coastal landforms and a type of Dune, dune system that are exceptionally flat or lumpy areas of sand that form by wave and tidal action parallel to the mainland coast. They usually occur in chains, consisting of anything fro ...
s along the Atlantic coast of North America from
Sable Island Sable Island (french: île de Sable, literally "island of sand") is a small Canadian island situated southeast of Halifax, Nova Scotia, and about southeast of the closest point of mainland Nova Scotia in the North Atlantic Ocean. The island i ...
off
Nova Scotia Nova Scotia ( ; ; ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. Nova Scotia is Latin for "New Scotland". Most of the population are native Eng ...
, to
Cumberland Island Cumberland Island, in the southeastern United States, is the largest of the Sea Islands of Georgia. The long-staple Sea Island cotton was first grown here by a local family, the Millers, who helped Eli Whitney develop the cotton gin. With its ...
, off the coast of
Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...
. Even though these are often referred to as "wild" horses, they are not truly "wild" if wildness is defined as having no domesticated ancestors. In 1995, British and French explorers encountered a new population of horses in the Riwoche Valley of
Tibet Tibet (; ''Böd''; ) is a region in East Asia, covering much of the Tibetan Plateau and spanning about . It is the traditional homeland of the Tibetan people. Also resident on the plateau are some other ethnic groups such as Monpa people, ...
, unknown to the rest of the world, but apparently used by the local
Kham Kham (; ) is one of the three traditional Tibetan regions, the others being Amdo in the northeast, and Ü-Tsang in central Tibet. The original residents of Kham are called Khampas (), and were governed locally by chieftains and monasteries. Kham ...
ba people. It was speculated that the
Riwoche horse The Riwoche horse is a dun-colored, pony-sized horse indigenous to northeastern Tibet. It came to international attention in 1995, at which time its primitive appearance and small size led to speculation that it might be an evolutionary link ...
might be a
relict A relict is a surviving remnant of a natural phenomenon. Biology A relict (or relic) is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas. Geology and geomorphology In geology, a r ...
population of wild horses, but testing did not reveal genetic differences with domesticated horses, which is in line with news reports indicating that they are used as pack and riding animals by the local villagers. These horses only stand tall and are said to resemble the images known as "horse no 2" depicted in cave paintings alongside images of Przewalski's horse.


See also

*
Horse behavior Horse behavior is best understood from the view that horses are prey animals with a well-developed fight-or-flight response. Their first reaction to a threat is often to flee, although sometimes they stand their ground and defend themselves or ...
*
Domestication of the horse A number of hypotheses exist on many of the key issues regarding the domestication of the horse. Although horses appeared in Paleolithic cave art as early as 30,000 BCE, these were wild horses and were probably hunted for meat. How and when hors ...


References


Citations


Bibliography

* Equid Specialist Group 1996. Equus ferus. In: IUCN 2006. 2006 IUCN Red List of Threatened Species. . Downloaded on 22 May 2006 fro

* Moelman, P.D. 2002. Equids. Zebras, Asses and Horses. Status Survey and Conservation Action Plan. IUCN/SSC Equid Specialist Group. IUCN, Gland, Switzerland. * {{DEFAULTSORT:Wild Horse Equus (genus) Mammals described in 1785 Types of horse