Unchanged for 200 million years because evolution couldn't improve the design, the saltwater crocodile is a 2,200-pound ambush predator with the strongest bite ever measured in the animal kingdom. Its death roll can dismember prey in seconds, and it can lurk motionless for hours before exploding from the water at terrifying speed. Dinosaurs went extinct; this thing didn't.

The undisputed king of the African savanna, the lion commands respect with a bone-crushing bite force and claws that can shred steel-drum lids. Hunting in coordinated prides, a male lion's 550-pound frame and thunderous roar can be heard from five miles away. Few animals dare challenge this apex predator on its home turf.