Monday, September 9, 2019

On the ambling gait of horses


About 20 to 30 breeds of modern horses carry what is referred to as a "gatekeeper" gene which produces gaited pacers, or amblers—a trait highly prized during the Middle Ages. The jennet and palfrey were considered prized amblers, noted for their smooth rides. Good for traveling long distances.
 
Medieval ambling palfrey. Folio 8r of an Apocalypse. British Museum—Wiki

If you've ever ridden a horse any distance at spanking diagonal-legged trot, it's a jarring staccato of a ride that's murder on the spine and the innards. The smooth ambling, or pacing gait, where one foot never leaves the ground, overstepping, and/or front and back legs moving, not diagonally, but laterally as one unit on each side, like the four-beat walk, but much faster—softens the blow, so to speak. 

Ambling is like having a horse with good shocks and extra speed gears. Think four on the floor, plus two or three extra overdrive gears in car terms. Most horses have three or four gaits: the four-beat walk, the two-beat jog and the faster trot (some horses are unclear on the idea of jog, other can't grok the idea of canter), the three-beat rocking horse canter, and the faster gallop where all four feet leave the ground. Amblers have one or two more gaits similar to a lateral trot. 

Amblers will rarely canter or gallop. Their gallop gear is wonky. Helgar, the Icelandic pony we rode, would begrudgingly gallop, and he preferred trotting to tölting. It was like riding a jackhammer on a knifeblade. But when he tölted, it was like riding on clouds. 

Not all amblers will naturally amble—some need tune-ups. But you can't train a non-ambling horse to amble. Amblers make up for a lack of a working galloping gear (in Icelandic terms), by tölting, or when they really burn rubber with the faster lugskeið or flying paces which is full blast tölting at 30 mph. That's almost as fast as a thoroughbred racehorse. But Icelandic ponies are not the only gaited horses, there are many old or isolated breeds that retain this archaic gene. Where did it come from?

(See Edward Muybridge's photo animated gif of a flying pacer).

During the Middle Ages, there was no such thing as the idea of a modern “breed” though hominids have been cross-breeding plants and animals for eons; selective inbreeding for specific dominant genetic traits is a modern concept. In the past, body “type” was used as a genetic breeding criteria. The Old English word breed comes from bredan which means to "bring young to birth." Not terribly enlightening or specific. The definition of the word breed has changed considerably since the Middle Ages.

During the agricultural revolution of the 18th c., farmer Robert Bakewell of Leicestershire, England, methodically bred superior sheep (Lincoln Longwool), Dishley Longhorn cattle (double the weight of other cattle), and strong workhorses (the Black Cart horse, ancestor of the Shire), by inbreeding livestock for specific traits via artificial selection vs. letting nature take its course, to strengthen and enhance certain traits. His animal husbandry experiments influenced the thinking of Charles Darwin in Origin of Species.

The Celtic horse/pony, with ancient Celtiberian origins, was a probable ancestral carrier of the ambling gene; still present in the surviving indigenous wild horses of Iberia, the Sorraia (a scrawny Guadalquivir marsh horse dubbed Marismeño by Columbus), and other rare breeds including the Garrano, Gallego, Asturcón, Pottok and Losino. (I use the word Iberia loosely vs. Spain and Portugal as the Iberian horses, whose shared ambling DNA traits predate the foundation of those political entities.)

These Iberian wild horses were also the probable ambling ancestors of all the New World gaited horse breeds including the Florida CrackerMissouri fox trotter (the ambling gait was called the fox trot), Saddlebred, StandardbredTennessee Walking Horse, and the Puerto Rican Paso Fino—and the myriad related Latin American ambling breeds. 

In the British Isles, the ambling gene was carried by the extinct Irish hobby, (foundation bloodline of the Connemara pony and the thoroughbred); the DartmoorExmoorFellHighland, and Shetland (but not the Fjord horse), all carry the ambling gene. 

During the early 19th c. like the beleaguered Kerry Bog pony, the tiny Faroe Island pony, a distinct breed related to the Shetland, and the Icelandic pony, was extensively exported to the UK, used as troglodyte pit ponies to haul coal—never to see the light again. The need for pit ponies was so great that almost none were left in the Faroes. 

The term, Irish hobby/hoby has an interesting linguistic lineage, hobin/obann in early Irish, or hobynis in early Scots (the preferred ride of Robert the Bruce), came from the French haubini and morphed into hobbeye; which is cognate with palfrey (Latin, paraveredus, a courier horse, from the Gaulish vorēdos. The German Zelter, or ambler is cognate with Icelandic, tölt.)

And one amang, an Iyrysch man, (he's referring to a hobelar)
Uppone his hoby swyftly ran... John Barbour, The Brus, 1375

Sweyn Forkbeard on a dappled palfrey.  Life of King Edward the Confessor, 13th c. Wiki

Oddly, two indigenous horse breeds in Northwest India—those weird-cross-eared horses of Marwari or Malani from the Jodhpur region of Rajasthan, and the Kathiawari, a desert war horse of the Gujarat, both have genetic ties to the Mongolian horse (not a pacer), and they are also gaited. Which considerably widens the origin of the ambling gene pool. Northern India, Iberia, Ireland, Iceland.

The native Northern European horses, including the Dartmoor and Exmoor ponies along with the Kerry Bog pony (all have a genetic link to Mongolian horses) are considered to be among the most ancient of breeds, possibly even Neolithic breeds, dating back to the Pleistocene era, along with the Sorraia and Garrano of Iberia, and all carry that gatekeeper gene. Convergent evolution? I think not.

Sadly most nations nearly slaughtered their ancient horse breeds, considering them superfluous and obsolete—especially after WWI, once the combustion engine was developed. Many countries actively slaughtered those horses carrying this rare ancient gene, for dogfood, or for eating the very grass their valuable blooded livestock needed. Those persecuted feral horses that escaped to the fens and bogs of Europe managed to survive, keeping the rare genetic pool alive, but just barely. Once a population gets too low, a genetic bottleneck occurs—which means lost gene variations.

Now here's the mystery: the recessive gatekeeper ambling gene DMRT3 is NOT present in most modern horse breeds, including the venerable Norwegian Fjord Horse breed (which throws a huge spanner into the notion that Icelandic horses and the nearly extinct Faroe ponies (related to the Icelandic horse) are solely descended from fjord horses. (I cannot fathom a chonky fjord draft horse tölting, let alone, traveling to Iceland on a tiny wooden Viking ship).

Pict on an ambling pony, with his carnyxBullien Stone, 9th c. Wiki

And yes, you read that right, the Irish Celts inhabited the Faroe Islands as well as Iceland long before the Vikings—and the only reason why the Icelandic pony is called a horse, is that there's no word for pony in Icelandic. Besides, all those island horses were diminutive. Think of Shetlands.


Nor is the recessive pacing gene present in the ancient Przewalski’s horse species. So where did it come from? Mongol horses? Tarpans? Who's on First? Since the ancestor of horses were once a New World species... nah.

The Mongol horse, an archaic breed and foundation stock for all Asian horses, including the Outer Mongolian Tuvan horse, has the most genetic variability of any horse, vs. the extreme bottlenecked Przewalski's horse, a distinctly separate species with extra chromosomes, saved from extinction because of ten horses found in European zoos. (The Botai horse of Kazakhstan may have been a Przewalski's horse, or a hybrid, but it's the earliest reference we have to domestication of the horse— if you consider eating them a form of domestication.)

It is surmised that some wild Mongol horses still exist alongside their more domesticated kin. They are all considered feral or semi-feral, somewhat like the American mustang. But, not all Mongol horses are one homogenous breed; there is the desert horse with big feet, the agile mountain horse, and the Steppe horse—which is used for racing. Has anyone looked at the other Mongol horses for that primitive ambling gene? 

There is some conjecture that the ambling gene might have been inherited from the Eurasian Tarpan, thought to be the original wild horse, Equus ferus ferus. There were two subspecies of tarpan, the forest, and the steppe horse. The Eurasian forest tarpan was the probable ancestor of the European horse of the Pleistocene era, made famous by the paintings on the cave walls of Las Caux, and Altamira. 

Herodotus described pale (dun?) wild steppe horses in what is now the Ukraine in the 5th c. BC. Sadly, the last tarpan, a diminutive grullo with a full falling mane (not a standing mohawk like the Przewalski's horse), and primitive markings, including a dorsal stripe and shoulder stripes, died in a Russian zoo in 1909. The last wild tarpans had been extirpated between 1875 and 1890. And "the last free-ranging mare was accidentally killed during an attempt at capture." (Wiki)
The name "tarpan" or "tarpani" derives from a Turkic language name meaning "wild horse". The Tatars and the Cossacks distinguished the wild horse from the feral horse; the latter was called Takja or Muzin. ... Most studies have been based on two preserved specimens but research has not positively linked the tarpan to Pleistocene or Holocene-era animals.—Wiki
Primitive wild horses still roamed free in Europe and Russia until the 16th century. There were captive wild horses in Russian and Polish zoos ca. 1750s, that were "small and strong, with robust limbs, a large thick head," small eyes, pinned ears, a shaggy dun, or mouse-colored coats with a light belly (primitive pangaré markings), "short dark manes and tails, and a beard." Their whinny was more like a donkey bray. And "They were also absolutely untameable." (Wiki) And no, they weren't wild asses, the European wild ass went extinct during the Pleistocene. 

It seems that the tarpan and Przewalski's horse shared the untameable gene, along with the equally vicious Syrian onager of the Middle East. (Untameable is the main difference between wild and domestic animals—and why zebras can't be domesticated).

So, it's possible the forest tarpan may have carried that ambling gene, but at this point, it's all pure conjecture.

According to Wiki:
In 2012, a DNAstudy found that horses from several gaited and harness racing breeds carried a mutation on the gene DMRT3, which controls the spinal neurological circuits related to limb movement and motion. In 2014, that mutation was found to originate in a single ancestor to all gaited horses....Ambling was described as early as the Hittite writings of Kikkuli. (Kikkuli was a Hurrian charioteer and "master horse trainer of the land of Mitanni.")

Unfortunately the Wiki article does not expand upon that single ancestor to all gaited horses.* But Kikkuli, that master horse trainer, who recorded the presence of amblers on his training regime treatise inscribed on cuneiform tablets. 

Kunga draft hybrids, 'Standard of Ur' mosaic, 3rd m BC, British Museum

While everyone else in the Middle East were using hybrid kunga asses to pull cumbersome war carts, the Hittite charioteers with their superior (Kabarda or Circassian?) war horses, quickly supplanted the kungas, and forged an empire that included Turkey, Syria, Lebanon and Northern Iraq. 

The ousted kunga asses were a hybrid between the large Syrian onagers (among the fastest of land mammals—at 40mph, they could easily outrun horses) that were bred with more tractable donkeys. (The hybrid kungas predated the horse-donkey hybrid mule by 1500 years. Imagine what could've happened to warfare advantage if horses and onagers had been crossed). 

So the perhaps the ambling gene arose somewhere in the Middle East. Back to the homeland of the Tarpan. The last known Syrian onager was shot in 1927 in Jordan, and the last captive onager died in a Vienna zoo that same year.

And here's an aside: it seems that ambling, a trait duly noted by the Hittites, would go a long way in ameliorating the origin of those odd amblers of northwestern India. From the Middle East to Iberia is an easy enough connection to understand, but to the bogs of Ireland? I guess we will never know the gene's origin, or why certain isolated horse populations retained the gene, despite the meteoric rise of the modern horse. But we're glad they did.

The oldest known horse sculpture found in the Vogelherd cave, Germany, was carved ca. 32,000 years ago. —Wiki

Note bene: I wrote this orphaned stub of a fragment originally in 2019, but never fully fleshed it out until June, 2023. But I am reposting it on the same date as the Kiger Horse post, as that was the genesis. The Google rabbit hole was big, very big.  I've probably written myself into too many tight corners with this one.

Genetic diversity within and between British and Irish breeds: The maternal and paternal history of native ponies

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