At depths where sunlight has never reached and pressure could crush a submarine like a soda can, life was long thought to exist only in the form of tiny microbes—until now.
A secret ecosystem in the abyss
The hadal zone—found more than 20,000 feet below the ocean’s surface—is among the most remote and mysterious regions on Earth. Beyond that depth, where darkness is absolute and conditions seem utterly hostile, scientists assumed only microscopic life could survive.
But the Kuril–Kamchatka Trench, one of the planet’s deepest points at 34,587 feet, has just rewritten that belief.
In 2024, a team of Chinese researchers piloted a submersible to the trench floor. What they found shocked them: not just bacteria, but thriving colonies of tube worms nearly a foot long, along with mollusks, crustaceans, and even sea cucumbers.
Scientists had accepted that microbes could eke out a living in such places, but larger creatures? That seemed impossible—until this dive proved otherwise.
Although scientists knew that microbes could thrive at these depths, they struggled to imagine that larger species could survive there. © Peng et al., Nature, 2025
Survival without sunlight
So how do these animals make it in such crushing darkness? Their secret is chemosynthesis.
Unlike most life on Earth, which relies on sunlight and photosynthesis, these deep-sea residents get their energy from chemical compounds like methane and carbon dioxide that seep out of cracks in the ocean floor.
The expedition found multiple zones, each home to its own distinct community of organisms—a patchwork of life in an otherwise desolate world.
The researchers discovered several types of areas that are home to different types of organisms. © NPG Press, Institute of Deep-sea Science and Engineering, CAS
The team’s findings, published in Nature, suggest similar ecosystems may be hiding in other trenches far deeper than we once thought life could exist.
The stakes for the deep sea
The discovery also puts a spotlight on deep-sea mining, an industry many nations—including China and the United States—are eager to expand in search of rare minerals.
Scientists warn that disrupting these fragile ecosystems, which we’ve only just begun to understand, could wipe them out before we even know what we’ve lost.
It’s a reminder that some of Earth’s greatest mysteries aren’t waiting for us in space—they’re lying silent, far below the waves.
Angèle Ingrand
Science journalist
Fascinated by nature and zoology since childhood, this journalist chose to share her passion through journalism after completing her biology studies. Now in her third year at the journalism school in Cannes, she works at Futura, where she is dedicated to making science accessible and raising public awareness of environmental issues.
