The Sorraia is a rare breed of horse indigenous to the portion of the Iberian Peninsula, in the Sorraia River basin, in Portugal. The Sorraia is known for its primitive features, including a convex profile and dun coloring with primitive markings. Concerning its origins, a theory has been advanced by some authors that the Sorraia is a descendant of primitive horses belonging to the naturally occurring wild fauna of Southern Iberia. Studies are currently ongoing to discover the relationship between the Sorraia and various wild horse types, as well as its relationship with other breeds from the Iberian Peninsula and Northern Africa.
Members of the breed are small, but hardy and well-adapted to harsh conditions. They were captured and used by native farmers for centuries, and a remnant population of these nearly extinct horses was discovered by a Portuguese zoologist in the early 20th century. Today, the Sorraia has become the focus of preservation efforts, with European scientists leading the way and enthusiasts from several countries forming projects and establishing herds to assist in the re-establishment of this breed from its current endangered status.
Characteristics
thumb|The characteristic convex facial profile
The Sorraia breed stands between high, although some individuals are as small as The head tends to be large, the profile convex, and the ears long. The neck is slender and long, the withers high, and the croup slightly sloping. The legs are strong, with long pasterns and well-proportioned hooves. These horses have good endurance and are easy keepers, thriving on relatively little fodder. They have a reputation for being independent of temperament, but tractable.
thumb|right|[[Foal with primitive markings and "hair stroke"]]
On adult horses, the lay of the hair can create the appearance of stars and flags on the neck and chest. Also due to the lay of the hair, newborn foals can appear to have stripes all over, reminiscent of zebra stripes. The breed standard refers to this as "hair stroke".
Sorraia are generally dun or a dun variation called grullo. Dun coloring includes primitive markings such as a black dorsal stripe, black tipped ears, horizontal striping on the legs and a dark muzzle area. The dark muzzle area is in contrast to some other dun-colored horse breeds, who have light-colored muzzle areas and underbellies, possibly due to the presence of pangare genetics. Sorraia horses have bi-colored manes and tails with lighter colored hairs that fringe the outside of the longer growing black hair. Purebred Sorraia occasionally have white markings, although they are rare and undesired by the breed's studbook. d'Andrade hypothesized that the Sorraia would be the ancestor of the Southern Iberian breeds. Morphologically, scientists place the Sorraia as closely related to the Gallego and the Asturcon, but genetic studies using mitochondrial DNA show that the Sorraia forms a cluster that is largely separated from most Iberian breeds. Some evidence links this cluster with Konik and domestic Mongolian horses. Genetic evidence
Multiple authors have suggested that the Sorraia might be a descendant of the Tarpan based on shared morphological features, principally the typical color of its coat. Other authors simply state that the Sorraia has "evident primitive characteristics", although they do not refer to a specific ancestor. Such conflicting results can arise when a population passes through a genetic bottleneck, and evidence suggests that the Sorraia, among other rare breeds, has recently passed through a bottleneck, Analysis of mtDNA has been performed on Mustangs in the western United States that show similar mtDNA patterns between some Mustangs and the Sorraia breed. At the time of d'Andrade's initial meeting the breed, the horses were ill-regarded by native farmers, although they were considered hardy native fauna that lived off of the uncultivated lands and salt marshes in the local river valleys. For centuries, peasant farmers of the area would occasionally capture the horses and use them for agricultural work, including threshing grain and herding bulls.
In the 1920s and 1930s, as mechanization became more prevalent, both wild and domesticated breeding stock diminished to almost nothing, and d'Andrade, along with his son Fernando, encouraged the conservation of the breed. These horses were kept in a habitat similar to their native one. with a small population in Germany.
American preservation efforts
thumb|right|A [[Kiger Mustang mare of Sorraia phenotype used as a foundation broodmare on Manitoulin Island in Ontario]]
Two Sorraia stallions were imported to the United States in the early 21st century. In 2006, another Sorraia stallion was imported to Canada where a Sorraia Mustang Preserve has been established on Manitoulin Island in Ontario.
Naming
Dr. Ruy d'Andrade gave the breed their name of "Sorraia". but the Sorraia and the Marismeño have evolved into two different breeds over time. Today, the name Marismeño refers to a population of semiferal horses living in Doñana National Park in Spain.