
What animals live at the bottom of the Mariana Trench?
It’s almost 11km down to the deepest point on the Earth’s surface so surely nothing can survive at that depth… surely?
Asked by: Claire Marshall, Reading
When Don Walsh and Jacques Piccard made the first expedition to the bottom in 1960, they reported seeing a flatfish but they didn’t take photographs, and other marine biologists now think this was probably a sea cucumber.
No other survey has found fish deeper than 8,145m and the Mariana Trench reaches down to almost 11km. But there are shrimp-like amphipods the size of rabbits living there, and strange saucer-sized animals, called Xenophyophores. These look like coral but are actually a single cell with multiple nuclei, that feeds like an amoeba, by engulfing small particles of ocean debris.
Read more:
- Are all the world’s oceans at the same level?
- How long would a pebble take to reach the bottom of the Mariana Trench?
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Authors

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
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