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	Large tooth is Equus sp. and small one is nannippus sp.. Horses began their evolutionary cycle in North America and became extinct here about 10,000 to 12,000 years ago. Before they did though, some of them migrated to Eurasia. The Spaniards then reintroduced horses to the Americas in the early 1500s, bringing them full circle.
	If you look at the chewing surface of an Equus (modern large horse) and the smaller Nannippus, the small tooth has an isolated island -- or protocone -- at the top of the tooth's chewing surface. While the island is only marked on the upper molars, it is a way of separating a juvenile Equus from an adult Nannippus. The larger tooth does not have a complete island.
	Horse (Equus) astragalus or ankle bone.
	Horse (Equus) cannon bone and toe bones (dark) compared to a modern horse's toe bones (white).