Riwoche horse

File:Riwoqê County.png

Location of Riwoqê County within Tibet, where the horses were found.

Riwoche horse
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Perissodactyla
Family:	Equidae
Genus:	Equus
Species:	E. ferus caballus

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 between the prehistoric wild horse and the modern domestic horse. Subsequent analysis, however, demonstrated that it is genetically indistinguishable from modern horses.

Nomenclature

The horse was named by European explorers after its home region, Riwoqê County, in Kham, northeastern Tibet. Riwoche is pronounced "Ree-woe-chay" (IPA /ˈriːwoʊtʃeɪ/).

Discovery

The breed was first observed by non-Tibetans in October, 1995 in an isolated, 27 kilometres (17 mi) long valley reached only by crossing a 5,000 metres (16,000 ft) mountain pass, by a team of six explorers led by the French ethnologist Michel Peissel. While on an expedition to study another horse breed that Peissel had previously observed in 1993, the Nangchen horse, his team came upon a number of small horses in an isolated valley in the Riwoche region of Tibet.

Peissel told The New York Times, "They looked completely archaic, like the horses in prehistoric cave paintings. We thought it was just a freak, then we saw they were all alike." He added to Time magazine, "The beige coat, black and bristly mane and the stripes on its back legs and back are similar to [features of] the most ancient breeds we know. The angular shape of the body, and the head in particular, is like that of the horses found in the Stone Age cave paintings."

He told CNN's Peter Humi, "It took me two years to get permission to go to that area, and it will be very difficult to get permission to go back and export them. As you know, Tibet is occupied by the Chinese and they're not very keen on foreigners visiting these remote areas."

The horses were unknown to the rest of the world, but familiar to and used by the local Bon-po people. These pre-Buddhist farmers would catch the horses with a lasso when they wanted to ride them or pack them, then set the horses free until they were needed again.

Peissel and his crew obtained blood samples from the herd for DNA testing; the samples were given to Steven Harrison, a geneticist at the Royal Agricultural College in Cirencester, England. Before doing the tests, Harrison told Time, "It would be premature to say these horses are a new species. Without tests you cannot tell whether it's a population of wild horses that have evolved in isolation or a feral population that was once domesticated and has gone wild. The Chinese, of course, were great horsemen even before we had horses in Europe."

A British equine psychologist accompanying the expedition, Dr. Ignasi Casas, of the Royal Animal Health Trust at Newmarket, Suffolk, England, theorized that the Riwoche horse was a relict population of wild horses due to living in near-complete isolation from other breeds for a very long time. Pointing out that the breed's isolation preserved its characteristics, Casas said, "It looks very primitive and very tough. Horses in the adjacent areas are very different." One explanation for their archaic form, he said, is that the valley where they were found is closed off on both sides by very tall passes. "Horses would not roam through those passes easily because at that altitude there is no grass, no food to survive."

Other hypotheses suggested that it might be an evolutionary link between the prehistoric horse and the domesticated horse, but testing did not reveal genetic divergence from other horses, which was in line with news reports that the horses were domesticated, used as pack and riding animals by the local residents. Peissel noted the phenotypical resemblance of the Riwoche horse to the Przewalski's horse, but expressed a strong belief that the two are not closely related.

Casas said, "It's an exciting find because horses have bred and mixed and traveled all over the world, but this one so far seems unique."

Characteristics

Riwoche horses are pony sized, standing only 12 hands (48 inches, 122 cm) tall. They are dun in color, with angular bodies, upright manes and primitive markings including a dorsal stripe down their spine and striping on the back of their legs. These features are similar to those of some other modern horse breeds thought to have ancient roots. They also have small ears, rough coats, small jaws, straight, flat foreheads, and unique, narrow "duck-bill" nostrils.

Their unusual appearance led Peissel to speculate that they could be "living fossils." He noted that they strongly resembled horses in prehistoric cave art, a "number two" horse distinct from but often pictured alongside horses with a body type resembling the Przewalski's Horse.

Status

This taxon has not yet been assessed for the IUCN Red List.

Subsequent discoveries

On the same expedition, Peissel also observed other isolated and unique species of megafauna, including a rare white-lipped deer, as well as what is believed to be the source of the Mekong river. Near the upper Salween River, the caravan of six Europeans saw large forests, which did not appear on any maps, of enormous, untouched conifers, willows, birches and other trees. Peissel said, "It was very peculiar because this was a very bleak, icy and grassy high plateau and suddenly there were these forests in the middle of the tundra. They could be remnants of the ancient forests that once covered much of Tibet. Because access is so difficult and there are no bridges, the forests have survived the axes of the Chinese, who are logging Tibet intensively."

In popular culture

In an essay originally appearing on the website for the Nova television series episode The Beast of Loch Ness (aired January 12, 1999), Peter Tyson, an online producer for the program, discussed the "discoveries" of various animals, including okapis, elephant birds, Komodo dragons, Giant pandas and others, as well as the Riwoche horse.

See also

• List of megafauna discovered in modern times
• Nangchen horse
• Tibetan pony
• Mongolian horse
• Wild horse

References

• http://www.nytimes.com/1995/11/12/world/a-stone-age-horse-still-roams-a-tibetan-plateau.html?pagewanted=1