With over 200 individuals of western horse recovered from Rancho La Brea, paleontologists have determined that this species had a strong resemblance to the modern East African zebra and the extinct South African quagga even though it wasn't closely related. Scientific studies on the western horse suggest that the species underwent a small, yet significant reduction in body size near the end of the last Ice Age. This change in body size may be the result of changing conditions in both climate and vegetation.