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.
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