A group of horses is called a herd. Like the other members of the equid family, zebras and asses, horses form extended family groups in which individuals communicate with one another through vocalizations, mouth gestures and ear and tail movements.
All species of equids are originally native to the grasslands and deserts of Africa and Asia, though humans have transplanted them to many different terrains and climates around the world. Somewhat unsurprisingly, the domesticated horse, a descendant of the wild horse, is currently the most numerous of all equid species. Habitat destruction has endangered most of the wild equid species.