Sabre-tooth tigers and dire wolves were in trouble before they vanished

Along with the mammoth and the dire wolf, the sabre-tooth tiger was a casualty of the Quaternary Extinction, a die-off that happened between 50,000 and 10,000 years ago that seems to have affected big animals in particular.Exactly what caused the is still a matter of debate. (Two popular possibilities are a warming in the climate, and the arrival of humans.) A new paper by Hugo Schmökel, a veterinary surgeon at the Evidensia Academy, a veterinary college in Sweden, and his colleagues, suggests that, for both the sabre-tooth tiger and the dire wolf, inbreeding played a part.