The horse has had a significant effect on history, from its earliest start, when it was eaten, through the Middle Ages, where it had a remarkable effect on the Agricultural Revolution. Horses have been used as beasts of burden, companion animals, war creatures, and rapid transportation.
Equidae (the horse family) like that of various other mammals first materialized at the start of the Eocene era about 57 million years ago. Earth was a significantly different environment at that time. The weather was much warmer; the topography was primarily wooded, with meager wide-open grasslands and prairies. Animals were living at the Arctic Circle. Europe and North America were a good deal closer together physically. Because of the extinction of the dinosaurs and other animals 65 million years ago, several biological voids were formed, among them recesses for medium-to-large-sized herbivores.
The ancestors of the modern horse walked only on the tip of the third toe and both side toes. Skeletal remains display wear on the back of both sides of the metacarpal and metatarsal bones, which are the leftovers of the second and the fourth toe. Modern horses keep the splint bones; some consider them useless attachments, however, they do perform an important function in supporting the carpal joints (front knees) and even the tarsal joints (hocks).
Over a great deal of time, the teeth of the horse experienced major changes. The original teeth were short, "bumpy" molars that steadily altered into long (as much as 3.9”), coarsely cubical molars endowed with flat grinding surfaces.
Along with the evolution of the teeth, the lengthening of the front part of the head is obvious; the rearward set eye sockets, as well as the short neck of the ancestors lengthened over time, along with equal protraction of the legs; and lastly, the size of the body grew as well.
The ancestors of the modern horse are:
Eohippus (dawn horses) existed 57 million years ago but are now extinct They galloped in the woods in North America and Eurasia, were small horses (about 10 – 20” tall, weighing 9 - 25 lbs.), with slender legs, having four-toed forefeet and three-toed hind feet, browsing herbivores who dwelled in herds on the prairies.
Mesohippus existed 30 - 40 million years ago, lived in the woodlands of North America, was small in size, 4 feet long and 75 pounds, had three-toed front feet, and ate plants.
Merychippus existed 10-17 million years ago on the plains of North America; was large, about 6 feet tall and weighed 1,000 pounds; resembled modern horses, but was somewhat larger; had vestigial side toes on the front and hind feet that did not contact the ground, so was able to run similarly to how a horse would; and was an herbivore. They were also distinguished by the broadly set eyes positioned high on top of its long, horse-like skull.
Pliohippus existed around 12 million years ago; was very similar in appearance to the modern horse, but it had two hardly evident long extra toes on both sides of the hoof; long and slim limbs that reveal a quick-footed steppe animal; was approximately six feet high, and weighed one thousand pounds; and ate plants. Its habitat was the plains of North America, specifically Nebraska and the Dakotas.
Equus caballus (modern horse) was introduced to North America in the 1500s when Christopher Columbus brought them here on ships from Spain on his second voyage to the new world. It is a wild horse and is known as the Mustang. They have strong legs; have hard hooves (one toe per foot) to tolerate many different types of ground conditions; and when you see them they look dirty and mangy from roaming the terrain. They range from 698 – 992 pounds, are herbivores, and generally stay together in groups/herds for protection.
The horse came to be dominated quite some time after he ox and ass and yet later than the onager and the reindeer or,...