Modern horses are believed to be descendants of those introduced by Spanish settlers in North America during the 16th century. Horses naively roamed North America until approximately 10,000 years ago, when they became extinct. The cause of this extinction is unknown, although climate change and hunting are probable factors.
Eohippus, or the "dawn horse," is believed to be one of the first ancestors of horses. It is characterized by its diminutive stature and toes that each end in a hoof-like structure. The Eohippus has origins that date back over 1 million years ago. Modern horses, in comparison, have one hoofed toe on each foot and vestigial toes that resemble bumps along the lower leg.Learn More
Adult horses lie down during REM sleep, and sometimes they also lie down during the day to rest or sun bathe. Young foals commonly sleep lying down. Horses only lie down for short periods because they are adapted to sleep on their feet and awake quickly to flee predators.Full Answer >
The average life span of a domestic horse ranges between 20 and 30 years, though that depends heavily on the conditions in which the horse is raised and the breed of the horse. A horse does not reach full maturity until age 5.Full Answer >
Horses typically sleep standing up, though they do lie down during REM sleep. They stay upright even when unconscious due to ligaments and tendons within their legs that lock into place when their hips rotate slightly during rest. This system of ligaments and tendons is called the stay apparatus.Full Answer >
According the Bureau of Land Management, feral horses can be found in Arizona, Nevada, Wyoming, Montana and North Carolina. Modern horses are descended from species that originated in Eastern Europe, Asia and Mongolia, and wild specimens still live in these regions.Full Answer >