A new study finds microplastics in nearly every organ of stranded sea turtles, including their reproductive systems.

Jellyfish are among the most fascinating creatures in the world. Without brains, hearts, eyes, or bones, they somehow manage to survive and thrive in the ocean, arguably the harshest environment ...

This story appears in the October 2018 issue of National Geographic magazine. Moon jellies, which are found in shallow bays around the world, look like small, not entirely friendly ghosts.

What most of us would recognise as a jellyfish - the otherworldly, gelatinous aquatic animals renowned for their sting-filled tentacles - is actually just the final stage of these animals' life cycle.

Jellyfish are known for drifting to and fro at the whim of ocean currents—but not all species are so passive. The millions of golden jellyfish that pack Palau’s Jellyfish Lake spend much of ...