Turtles return to the beaches where they hatched to lay their own eggs years later.

The longer version

Magnetic cues help guide the return, since the field varies in strength and inclination from place to place, giving a rough coordinate that sharpens as an animal closes on the right coastline. Chemistry supplies the final detail: young remember characteristics of their home water during the first frantic swim outward.

Females haul ashore at night, excavate a chamber with the hind limbs and cover the clutch before crawling back. Sand temperature during incubation decides sex in many species. Hatchlings scramble toward the brighter seaward horizon, then swim steadily away from land. Currents carry the young across ocean basins, and floating weed offers cover and food.

Where this entry sits

Oceans and Sea Life looks at the salt water that covers most of the planet, from crashing waves and tides to the darkest deep-sea trenches. Expect notes on coral, fish, whales, sharks, jellyfish, shells, and the strange creatures that live far below the surface. The full list sits on the Oceans and Sea Life page, where every entry is listed in order.