Out of South America
Genetic analysis shows that mountain lions originated in South America about 6.5 million years ago, when the species shared a last common ancestor with African cheetahs and jaguarundi. Just as human genetic variation is richest in Africa, where Homo sapiens has lived longest, the genetic diversity of South American mountain lions is exceptionally rich.
Shown above is a genetic family tree of mountain lions. From this type of work researchers have learned that mountain lions in North America, though historically spread across the entire continent, were descended from a single tiny population. Those founding cats immigrated from Central America about 10,000 years ago after a wave of mass extinctions saw 80 percent of North America's large vertebrates die out, including its original mountain lions.
Image: Culver et al., Journal of Heredity