Speculations, conjecture, most likely, it is believed, artistic renderings of what might have been, is that provable fact?
An excerpt from an article.
[The eohippus is an extinct prehistoric animal that is known as the “dawn horse.” It lived in the early Eocene era, about 50 million years ago. It probably looked like a miniature, spotted, cloven horse and was bigger than a fox. It was probably the size of a small dog, with a small thin tail. It lived in swamp-like forests, hid from predators in the shadows, and lived off the leaves of bushes and short trees. As time went by, eohippus changed. But for 20 million years, it didn’t change that much, evolutionarily speaking. Flash forward in time to a moment slightly before ours. There now exist paleobiologists. For many decades, they considered
Eohippus to be the linear ancestor of
Equus, the modern day horse.
For many decades, scientists considered Eohippus the ancestor of the modern-day horse.
Then new science replaces old science, and this idea changes. New science explains that the evolution of the horse is non-linear, like a many-branched tree.
Equus happens to be the only branch of the horse now in existence.
Eohippus is still considered an ancestor of
Equus, but in a less linear way. For some reason, scientists seem to know more about the evolutionary lineage of the horse than any other animal.
Extinct equids. True to scale.
Also, there is now the idea that
Equus is not the goal, or the crowning jewel, of a naturally-selected lineage.
As part of this many-branched tree, the indigenous horse died out in North America about 12,000 years ago. The Spanish brought domestic horses to the New world at the end of the 1400s. Therefore, if you encounter wild horses in the United States, they are feral.]
eohippus labs: Who we are, how we started, and where we think we might be going | Jacket2
They are still "horses" just like a wolf and a chiwawa are still "dogs".