(CNN) — Only a scattering of light penetrates the deep water, more than 300 feet beneath the ocean surface off the coast of Guam. It’s like twilight to the human eye, even in the middle of the day.

GUAM — Only a scattering of light penetrates the deep water, more than 300 feet beneath the ocean surface off the coast of Guam. It's like twilight to the human eye, even in the middle of the day.

This zone contains a vast amount of marine life, potentially over 90% of all ocean life, and supports important commercial and recreational fisheries. Creatures in the twilight zone help mitigate ...

Dive into the depths of the ocean to discover seven rare deep-sea creatures so strange and elusive, you won't believe they exist.

The deep sea is cold, dark and under immense pressure. Yet life has found a way to prevail there, in the form of some of Earth's strangest creatures. Since deep-sea critters have adapted to near ...

Deep-sea mining is threatening vital marine life in the ocean’s “twilight zone,” reveals new research. The findings raise "urgent concerns" about long-lasting effects if large-scale commercial mining ...