The Mariana Trench is deep. Very deep. I’d go so far as to say very, VERY deep. At its deepest point – Challenger Deep – the trench dips to 10.994 kilometers, or 6.831 miles. The weight that far underwater is simply crushing, and very little actually lives down there. Very little was actually increased by one recently, as a never before seen snailfish was observed near the bottom of the Mariana Trench. This fish smashed the previous record for deepest swimming fish by almost 500 meters, swimming at a depth of 8145 meters, a place where mostly crustaceans dare to tread.
This new fish was observed by the University of Aberdeen. They’d put out bait to try and attract sea life, but they never expected to see this small tissue-like creature swim past their camera. The expedition leaders described the cartoonish head of the fish and its incredibly delicate body. “You can see its liver through the side of the fish. It’s like tissue paper being dragged through the water.”
The bad part of this discovery – at least when it comes to the scientific aspect of it – is that they had no way to catch the fish. It cannot be scientifically categorized or even given a name until a specimen has been caught. That will have to wait for another trip down to the trench.
As for how fish can even survive that deep? Co-leader of the expedition – Alan Jamieson has some ideas:
Jamieson and colleagues believe there is a limit to how deep a fish can live, and this new record-holder is right at the edge. Below about 26,900 feet (8,200 meters), a fish’s body hypothetically can’t produce any more of a substance called an osmolyte, which helps their cells withstand the incredible pressures of the deep sea.
“The deeper you go, the higher the concentration of this substance,” Jamieson says. “When you get to 8,200 meters, there’s no way a theoretical fish can produce more.” If it were to go any deeper, the pressure would likely crush its cells, he says.
“If a fish can go deeper, it’s different from any other fish on the planet.”
Another view of this newly discovered fish: