Thoroughbred horses live in pastures and grassy lands, forming herds and eating during the summer months. They are physically large mammals with long tails that live longer when fed by humans, and are known to stand while sleeping as they are born to race. The document provides information on thoroughbred horses' habitat, behaviors, physical adaptations, and fun facts, citing resources from Pebblego, eHow, Britannica, and Bing Images.