 Although it is known that the Sorraia developed in the southern part of the Iberian peninsula , the breed was isolated and unknown to science until the 20th century . Despite the lack of documentation , attempts have been made to reconstruct its history . <unk> parietal art images in the region depict <unk> with a distinct likeness to the Sorraia , with similar zebra @-@ like markings . 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 . Spanish conquistadors took Iberian horses , some of whom closely resembled the modern @-@ day Sorraia , to the Americas in their conquests , probably as pack animals . <unk> between the Sorraia and several North and South American breeds are shown in the dun and <unk> coloring and various physical characteristics . This evidence suggests that the Sorraia , their ancestors , or other horses with similar features , may have had a long history in the Iberian region and a role in the creation of American breeds . 
