Surgeon aims to diagnose deformities of extinct saber-toothed cats

La Brea Tar Pits

STICKY SITUATION  At the La Brea Tar Pits in today’s Los Angeles, mastodons, dire wolves, saber-toothed cats and thousands of other creatures — prey and predators — were trapped and later excavated.

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Robert Klapper has examined scores of damaged and diseased human knees, hips and shoulders.