A FARMS report notes that the Book of Mormon mentions horses, yet these animals seem not to have been known to native Americans who greeted the Spaniards upon their arrival in the New World in the sixteenth century. Moreover, archaeological evidence for the presence of the horse in the pre-Columbian Americas is presently scant and inconclusive. How can this be explained? Careful consideration of this question begins with an examination of what the Book of Mormon says and does not say about horses.
Horses are mentioned only once in the land northward during the Jaredite period--that is, during the prosperous reign of King Emer around 2500 B.C. and before the great drought sometime in the third millennium B.C. (see Ether 9:19, 30-35). Since horses are not mentioned again in the Jaredite record, it is possible that they became extinct in the region north of the narrow neck of land following that time.
However, small herds of animals in a limited region sometimes leave no archaeological remains. Even if horses had been abundantly used and had been a vital element in the culture of Book of Mormon people (a claim never made by Book of Mormon writers), one cannot assume that evidence for this would be plentiful or obvious from the current archaeological record.
"It is probable," writes Jacques Soustelle, an authority on the Olmec, "that the Olmecs kept dogs and turkeys, animals domesticated in very early times on the American continent, but the destruction of any sort of bone remains, both human and animal, by the dampness and the acidity of the soil keeps us from being certain of this." We also know that the Norsemen probably introduced horses, cows, sheep, goats, and pigs into Eastern North America during the eleventh century A.D., yet these animals did not spread throughout the continent, or at least they have left no archaeological remains. The horse was the basis of the wealth and military power of the Huns of central Asia (fourth and fifth centuries A.D.). Nonetheless, according to S. Bokonyi, a leading authority on the zoological record for central Asia, "We know very little of the Huns' horses. It is interesting that not a single usable horse bone has been found in the territory of the whole empire of the Huns. This is all the more deplorable as contemporary sources mention these horses with high appreciation." [FARMS Research Report, "Horses in the Book of Mormon," [http://farms.byu.edu/web/reports/horses.asp]] [See the commentary on Alma 18:9]