where does the term dark horse come from
Dark horse The term began as horse racing parlance for a race horse that is unknown to gamblers and thus difficult to place betting odds on.
Horses in the United States The horse evolved in the Americas, but became extinct between 8,000 and 12,000 years ago. When the Spanish arrived on the American mainland in the 16th century, they brought horses with them and re-established the animals on the continent.