Why do crocodiles often keep their eyes and nostrils above water?

Crocodilians have a body plan suited to stealth hunting: eyes, nostrils, and ears are positioned high on the head, while the rest of the body can remain submerged. This allows them to observe and breathe with minimal exposure. It is especially effective when they lie nearly motionless in rivers, swamps, and estuaries, waiting for prey to approach. The arrangement also helps them stay concealed from both prey and rivals. This is a classic adaptation for an ambush predator.