Saber-tooths rule the Pleistocene Era but the arrival of the new cats, early snow leopards, cheetahs and jaguars, mark a turning point in the evolutionary track.

The era of the sabretooth is over and the biggest big cats ever, the lion and the tiger, become the kings of their respective habitats.

Changes the planet has undergone affects big cats, from the almost complete disappearance of American wildlife to the rise of man; threats to big cats' survival.