KOMODO NATIONAL PARK, Indonesia — The Komodo dragon, a 10-foot lizard native only to a scattering of islands in Indonesia, flicked its forked tongue. Two boys were standing nearby, the perfect size for dragon snacks.

A local guide shrugged at their unease and urged them closer to the reptile.

Komodo dragons resemble dinosaurs that missed their cue for extinction. Capable of smelling blood from miles away, they eat water buffaloes, deer and one another. Their saliva is laced with venom. Females are unsentimental enough to devour their own freshly hatched offspring.

Fatal attacks on humans are exceedingly rare, though they do happen. But the oversize lizard lounging near the two young tourists had just gorged on chicken and goat, and was lolling in the kind of digestive stupor Americans might experience after Thanksgiving.