This rich diversity decreased until only a few species, such as Camelops hesternus, remained in North America, before going extinct entirely around 11,000 years ago.[1] By the end of the Pleistocene, with the extinction of Paracamelus and Titanotylopus, Camelops was the only true camel remaining in North America and possibly both Americas. Camelops's extinction was part of a larger North American extinction in which native horses, mastodons, and other camelids also died out. Possible causal factors for this megafaunal extinction include global climate change and hunting pressure from human beings.