Curly haired horses revisited

I came across more information while researching the sencond edition of my book, regarding these odd horses, which have also been found in Patagonia.

Patagonian curly-haired horse. Andrea Sede, Source

Gerardo Rodriguez who was born in Maquinchao, and studied to be a veterinarian and his partner Andrea Sede own Yeguada Rodriguez, a small ranch in Maquinchao in the middle of the Province of Rio Negro (map). The place is arid, and located on by National Route 23 that crosses northern Patagonia from east to west, linking the Atlantic coast at San Antonio Oeste with Bariloche on Lake Nahuel Huapi. It still has many unpaved stretches. It follows the ancient native trail (see the spot on my interactive map of Muster's 1870 journey) and the railway.

The place is at the foot of the basaltic Somuncurá plateau, with little water and continental climate with hot, dry summers, and cold winters.

In 2006 Gerardo while working as a veterinarian for the government conducted a survey of the local ranchers in Somuncurá and to his surprise, he saw a curly-haired horse, when he asked the locals they said that "the horses have curls all winter, and in the summer they go" adding that there many more in the past.

Gerardo obtained several of these animals wild horses and now breeds them (Source). The herd now has 40 horses. This is their facebook with many photographs of their horses.

Unique genetic mutation

He also managed to have their DNA tested by the Texas A&M University that found that they have a unique mutation that is not linked to the known KRT25 mutation that causes curly hair in horses. A study has "identified the KRT25:p.R89H variant as responsible for the dominant curly trait, but a second dominant locus may also be involved in the shape of hairs within North American Curly horses." Yet, as it clearly states, other genetic sites may also cause curly hair. It is probably one of these "unknown" mutations that is present in the Maquinchao curlies.

Another paper cites literature and confirms another gene in curly hair, SP6: " KRT25 and SP6 were associated with curly coat in Bashkir Curly Horses and Missouri Foxtrotters by Thomer et al. A variant (KRT25:p.R89H) in the KRT25 gene was found to be responsible for the curly phenotype in North-American and French horses." But these two modified genes are not present in the Patagonian horses.

For the North American curly haired horses, the trait is caused by the KRT25 gene. If a horse is homozygous for it, it will have coarse hair, no mane or tail.

Homozygous means it carries two copies of the same allele, one from each parent. Heterozygous means it only carries one copy of the allele (see image above). If the "b" allele causes curly hair, a "bb" horse is homozygous for it, and a "Bb" or "bB" horse will be heterozygous.

In the case of heterozygous horses they are curly and have a mane and tail, but the hairs can be pulled out easily.

The mutation causesthe hair follicle to be curved, and as the hair grows, it curves.

The other mutation SP6 is also found in North America in a line detected in a horse called Curly Jim. These horses have curly hair and also an abundant mane and tail. This gene alters the shape of the follicle making it oval, which promotes the formation of curls.

If a horse has both genes KRT25, being epistatic, supresses the SPG variant, overriding it.

Interestingly the Lakota (or Dakota) people say that these horses existed in the days before the Europeans arrived in America. A statement by Claire Henderson published in 1991, tells that the Dakota/Lakota native people firmly believe that the aboriginal North American horse did not become extinct after the last Ice Age, and that it was part of their pre-contact culture:

"According to Elders, the aboriginal pony had the following characteristics: It was small, about 13 hands, it had a “strait” back necessitating a different saddle from that used on European horses, wider nostrils, larger lungs so that its endurance was proverbial. One breed had a long mane, and shaggy (curly) hair, while another had a “singed mane.”"

See: The Aboriginal North American Horse, Statement of Claire Henderson, History Dept. Batiment de Koninck, Laval University, Quebec, Canada. Feb. 1991. Online.

Regarding the Dakota people, Lieut. Col. Garrick Mallery Boston published an article in the USGS Bulletin (v.iii, no. 1) back in 1877, discussing the Calendar of the Dakota Nation. The entry for 1803 reads "They stole some curly horses from the Crows Some of these horses are still seen on the plains the hair growing in closely curling tufts resembling in texture the negro's woolly pile It is not however supposed that Frémont's celebrated woolly horse was of this breed The symbol is a horse with black marks for the tufts Crows are known to have been early in the possession of horses".

We have already mentioned Fremont's curly haired horse in a previous post (this horse was discovered in 1849). Read the online article from 1849.

Origin of the Patagonian curlies

Where did they come from. According to Gerardo (Source) there are three options:

1. They are from the original horses and mares brought by Pedro de Mendoza with his expedition to found a city (Buenos Aires) on the Rio de la Plata in 1536. The expedition failed due to the hostile natives, the lack of willingness to cultivate the land and the fact that an expedition sent up the Paraná River found that the Guarani natives in what is now Paraguay were friendlier and the weather better. So they abandoned the town in 1541 and heaed for Asunció. They burned the remains of Buenos Aires, and left some mares and stallions behind. These multiplied quickly on the vast grasslands of the Pampas and when the Spaniards returned in 1580 to found the town for a second time, they found tens of thousands of wild horses. Some of these horses evolved a curly hair mutation when they reached northern Patagonia.
2. They came from the expedition of the Franciscan Bishop Hernando de Trejo (I am quoting the Source, but disagree with this information as Trejo never visited Patagonia), who "in an expedition conducted into the South of Argentina between the end of the 16th century and the beginning of the 17th century introduced specimens of this race."
3. The horses came from the north, via the Strait of Bering and were originally from the Russian region of Bashkiria.
4. The last option is outlandish: "let's not ignore the story that tells about the role played by the horses used by the Knights Templar in their long journey transporting the Holy Grail escaping from Europe where they were being persecuted, as mentioned in the company's website". (I commented about these knights in a 2010 post).

We know that they existed in Argentina. Ricardo Hogg, (1941) in an article (Sobre vacas ñatas y otros temas camperos) reported that the curly horse was rare but not unknown in the Pampas region of Argentina however, by then "the curly haired horse, variety almost extinct".

The International Curly Horse Organization mentions them too (see here), the article says that they have not yet been able to identify the gene that causes this "curly winter coat in these Patagonian curly horses."

It also adds that the DNA tests gave surprising results. The horses weree not related to the Andalusian or Lusitano horses of Southern Spain (Mendoza's expedition sailed from Cadiz, and would have brought horses from the Andalucia region). Instead, they are closer to horses from northwestern Spain, from Galicia: " they were related to the smaller Celtic type horses located in Northern Iberian Peninsula. The Patagonian curly horses were genetically close to the Mexican Galiceno horse, which is thought to be a descendent of Northern Spain’s Celtic type horses brought to the Yucatan by Cortez during his conquest of the Aztec nation. The Galiceno horse is a much smaller horse than the Patagonian curly horses standing between 12 to 13.2 hands. There are less than 100 Galiceno horses in the States and Mexico. Other relationships were established by the dendrogram. Patagonian curly horses have a close association with ancestors of the Galiceno horse, which are the Portuguese Garrano and the Spanish Galician and Asturcon."

The following "tree" is included in the above mentioned article

Why would the Patagonian and the Mexican Galiceno horses be closer on the phylogenetic tree? By the way, they are also close to the Mallorquin and Menorquin breeds from the Baleares Islands.

However, Pedro Lozano, in his Historia de la conquista del Paraguay, Rio de la Plata y Tucuman written in the mid 1700s, (see p. 272 below) clearly states that Mendoza's expedition "brought from Andalucia to these provinces" no refernce to horses from Galicia or other parts of Spain.

It is clear that the horses in Patagonia have Spanish horse genes, but, could they have admixed with native pre-Hispanic horses that somehow survived in Patagonia after the megafaunal dying?

---

Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2025 by Austin Whittall ©