In one of the most hostile environments on planet Earth, life perseveres. Immense pressure, frigid temperatures, and geysers of incredibly hot fluid define this seemingly-inhospitable environment at the bottom of the world’s deepest ocean trench. How do researchers study such an ecosystem, and what could possibly survive in a biosphere like that? While getting there is far from easy, the abundance of life is truly amazing.
Flooring Facts And Figures
The Mariana Trench is the deepest ocean trench and the lowest point on the surface of the Earth, 7,000 feet lower than Mount Everest would reach if you turned it on its head. The bottom of the trench is 36,000 feet below sea level, where the last rays of light faded entirely from view some 23,000 feet above. The water down in the Challenger Deep lingers near freezing all year-round.
In the Mariana Trench, the water is a brisk 34 degrees Fahrenheit, and the pressure of all that water is enough to crush a human being in an instant. The only sources of warmth are hydrothermal vents, which spew superheated water and minerals as the ocean meets the magma seeping up from the mantle below. These vents can reach temperatures of 750 degrees Fahrenheit, but the water cannot boil because of the incredible pressure.
Strange Creatures Of The Deep
Anything living down in the depths of the Mariana Trench must be able to withstand the extremes. Millions of years of evolution have led to the development of many strange-looking creatures that dwell in the inky blackness of the depths below the abyss. Among those creatures are fish, like the frilled shark and the deep sea hatchetfish, which make up some of the deep ocean’s frighteningly toothy predators. The frilled shark has a pale, eel-like body with a flexible skeleton and two rows of widely-spaced, needle-like teeth. While it is creepy-looking, it seems relatively normal when compared to the hatchetfish, whose body is much taller than it is wide. The incredible thing about the hatchetfish is its ability to produce its own glow, called bioluminescence, to match the amount of light filtering down from above, so that if viewed from below, it remains unseen.
Most of the creatures dwelling in the depths of the trench, however, are invertebrates. Tubeworms most famously make their homes alongside the boiling hot hydrothermal vents, feeding off of the mineral-rich liquid they spew. Another type of deep-sea worm that makes its home in the Mariana Trench is the zombie worm, which feeds off of animal detritus, including bones, by excreting acid that breaks down the food into easily-absorbable nutrients.
It’s Not All Bad
Not everything that lives at the bottom of the ocean is terrifying. Sea cucumbers are goofy little blobs that live on the ocean floor and eat plankton and whatever leftovers they can sweep up from the sand. Sea stars also make their home in the dark waters, feeling along the ground for anything good to eat. The fleshy, skeleton-less bodies of these little critters have no problem surviving in the chilly, high-pressure depths.
Finally, the cutest creatures you’ll find in the Challenger Deep is also one of the smallest. Members of the fantastic group of living things called extremophiles, tardigrades love the boiling-hot waters near hydrothermal vents. These little organisms often referred to as water bears can survive just about anywhere, including the vacuum of space. They are as resilient as they are adorable, and they don’t mind the weather down there one bit.