Life In The Mariana Trench: Learn About The Marvellous Marine Mammals

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Life in the Mariana Trench facts include that the Mariana Trench is shaped like a horseshoe.

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According to studies, the Mariana Trench is believed to be the deepest part of the oceans on the planet.

It's a geological formation so large, vast, and majestic that it dwarfs Mount Everest in size. Unlike Everest, though, it is practically imperceptible to the naked eye and will remain thus for the rest of time.

While some huge animals such as sea cucumber and shrimp can be found at the ocean's deepest depths, bacteria are by far the most prevalent. Life in the deep water is far from easy, from the cold to the never-ending darkness and the incredible pressure. Some animals, like the dragonfish, produce their own light to attract prey, mates, or both. Others, such as the hatchet fish, have evolved massive eyes in order to catch as much of the rare light that reaches that depth as possible.

Some species simply try to avoid being seen, which usually involves turning translucent or red in order to absorb any blue light that has made its way down into the deep sea. Normally, these creatures produce calcium carbonate shells, but in the Mariana Trench's depths, where compression is 1,000 times greater than at the surface of the water, calcium carbonate dissolves. This means that the organisms will have to make a shell out of proteins, organic polymers, and sand.

Fish and other crustaceans, known as amphipods, can also be discovered in the murky depths, the largest of which resemble enormous albino woodlice and can be found at the very bottom of the Challenger Deep.

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How was the trench formed?

The trench was formed when two tectonic plates, the tectonic plate, and the Mariana plate, collided. The deepest part of the Mariana Trench was formed inside the subduction zone when two massive slabs of ocean crust collided. Only a single piece of oceanic crust fell into the Earth's mantle, the layer beneath the crust, by pushing and tugging underneath one another.

A deep trench arose above the bend in the sinking crust where the two pieces of crust joined. The Pacific Ocean crust bent beneath the Philippine crust in this case. The Pacific crust, also known as a tectonic plate, is around 180 million years old. In comparison to the Pacific plate, the Philippine plate is younger and smaller.

The cold, solid crust slid back into the mantle and was destroyed at the subduction zones. The trench, despite its depth, is not the location closest to the Earth's center. The radius at the poles is about 16 mi (25.75 km) shorter than the radius at the equator because the globe bulges at the equator.

As a result, portions of the seafloor beneath the Arctic Ocean are closer to the center of the Earth than the Challenger Deep. The water pressure on the trench floor is more than 8 tons per sq in (1124.91 kg per sq m). This is 1,000 times the pressure at sea level, or the equivalent of 50 jumbo aircraft heaped on top of one person.

As part of the Marianas Trench Marine National Monument, founded by President George W. Bush in 2009, a major section of the Mariana Trench is now a US-protected zone. The US Fish and Wildlife Service has granted permission for research in the monument, including in the Sirena Deep. The Federated States of Micronesia has granted permission to conduct research in the Challenger Deep.

Life In The Trench

The animals that live in the Mariana Trench's deepest depths are subjected to immense, extreme pressure and are always in the dark. Recent scientific research has proven that even in the most extreme conditions, there is a surprising amount of diversity in life.

Some microorganisms use substances like methane or sulfur, while others devour marine life at the bottom of the food chain. Xenophyophores, amphipods, and small sea cucumbers (holothurians) are the three most abundant organisms found at the Mariana Trench's bottom, according to Gallo. To reach the Challenger Deep, dead plankton must sink thousands of feet from the surface. As the deep valley is so far from the nearest landmass, food kinds are limited inside the Mariana Trench.

Amphipods are scavengers that look like shrimp and are typically found in deep-sea trenches. The holothurians are a strange, translucent sea cucumber that may be a new species. These are among the deepest holothurians yet discovered, and they are plentiful. The single-celled xenophyophores look like giant amoebas and feed by encircling and absorbing their prey.

Mud from the trench was transported to labs on dry land in special canisters and meticulously maintained in settings that replicate the crushing cold and pressure. In muck taken from the Challenger Deep, scientists discovered over 200 distinct bacteria. The hydrogen and methane generated by chemical interactions between saltwater and rocks are consumed by these clumps of bacteria. Microbial mats were also discovered at the Sirena Deep, which is located east of the Challenger Deep, during Cameron's 2012 expedition.

The animals in the Mariana Trench swim deeper than any other fish and take advantage of the lack of competition by eating up the abundant invertebrate prey found in the trench, according to the author of one study. Scientists discovered specimens of an odd organism known as the Mariana snailfish, which dwells at a depth of roughly 26,200 ft (7985.76 m), in 2017. The snailfish's little, pink body with few scales appears incapable of surviving in such harsh conditions, but this fish is full of surprises, according to recent research. A somewhat helpless-looking fish, it is not only at home here, but also one of the region's top predators.

The animal appears to be the dominant species in this habitat

Inside The Mariana Trench

The Mariana trench is a 1,580 mi long (2,542.76 km long) undersea rift in the Earth's crust, more than five times the length of the Grand Canyon. The narrow trench, on the other hand, is only 43 mi (69.2 km) broad on average.

The deepest point of the trench was initially identified during the Challenger expedition in 1875, which reported a maximum depth of roughly 26,850 ft (8,183.88 m) near the canyon's southern end using draglines. Compared to the Calypso Deep, the deepest point in the Mediterranean Sea, which is 17,280 ft (5266.94 m) deep, the Mariana Trench is much deeper and as shown by modern studies, it is actually 36,201 ft (11,034.07 m) deep in some parts.

The Mariana Islands are formed by a chain of volcanoes that rise above the ocean waves and reflect the Mariana Trench's crescent-shaped arc. Many bizarre submarine volcanoes are strewn around the islands.

An underwater canyon off the Philippines' eastern coast is so deep that you could fit Mount Everest within, with more than 9,800 ft (2987.04 m) to spare. It's easy to imagine the Mariana Trench, which is in constant, perpetual darkness and under tremendous pressure, as one of the most inhospitable locations on Earth. Despite this, life manages not only to survive but thrive, establishing its own distinct habitat.

The Mariana Trench is home to the world's deepest known locations, vents spewing liquid sulfur and carbon dioxide, active mud volcanoes, and marine life adapted to high pressure that is 1,000 times greater than at sea level. Given the lack of light at the surface, the next query is what these species eat. Bacteria can survive at these depths by eating methane and liquid sulfur released by the crust, and certain creatures will eat these as well.

Many, though, will rely on 'marine snow', or little particles of detritus that float down from the top of the ocean floor. A whale fall is the most severe example of this, and it is a huge boon for all deep-water species. The Mariana Trench consists of the deepest living fish that swim at a depth of 26,715 ft (8,142.73 m) below the surface.

The once undiscovered species of snailfish is ghostly white and has large wing-like fins and an eel-like tail. The species was captured many times by cameras sent down to the depths of the Mariana Trench. However, experts believe that this is the maximum depth at which fish may survive, implying that the trench's absolute depths are not hospitable enough to support fish due to the physiology of vertebrates. According to marine biologists, the existence of fish life under such extreme conditions is nearly inconceivable. According to the NOAA Office of Ocean Exploration, sea cucumbers are not alone on the seafloor.

Pollution In The Deep

Regrettably, the deep sea serves as a possible sink for dumped toxins and trash. According to a recent study performed by Newcastle University, human-made chemical substances that were prohibited in the '70s are still lurking in the ocean's deepest parts.

Researchers observed unusually high levels of persistent organic pollutants (POPs) in the fatty tissues of amphipods (shrimp-like crustaceans) collected from the Mariana and Kermadec trenches. In the journal, Nature Ecology & Evolution, it is mentioned that these chemicals included polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), which are extensively employed as electrical insulators and flame retardants.

From the '30s until the '70s, when they were finally prohibited, POPs were discharged into the environment as a result of industrial mishaps and landfill leaks. Alan Jamieson commented that the deep ocean or deep sea is believed to be untouched by humans and they do not influence the ecosystem down there, but new research from Newcastle University's Alan Jamieson indicates that this is not the reality.

Studies from other regions confirm the pollution levels in amphipods are similar everywhere. One of the studies from Suruga Bay one of the northwest Pacific's most polluted industrial zones reported the same levels of pollution. As POPs do not naturally disintegrate, they persist in the environment for decades, eventually reaching the ocean's bottom through tainted plastic trash and dead animals. The pollutants are subsequently passed down the food chain in the ocean, finally culminating in chemical concentrations substantially higher than those found at the surface.

The fact that such high amounts of these contaminants are found in one of the world's most remote and inaccessible environments underscores the effect that human activity is having on the Earth, as observed by Jamieson.

Humans And The Trench

During a globe tour in 1875, the HMS Challenger discovered the trench using newly invented sounding equipment. The HMS Challenger II sounded the trench once more in 1951. The two ships were given the names Challenger and Deep.

Bathyscaphe Trieste, a 'deep boat', reached the bottom of Challenger Deep in 1960. It was steered by US Navy Lieutenant Don Walsh and Swiss scientist Jacques Piccard. It was also the first vessel to reach the deepest part of the Earth.

It is not easy for human beings to swim to the deepest part of the planet. The expeditions sent did not last for long hours. Talking about individual achievements of swimming the deepest part of the ocean is not known. It is believed a man from the US Navy might have dived deep, but this information is not available to the public.

Here at Kidadl, we have carefully created lots of interesting family-friendly facts for everyone to enjoy! If you liked our suggestions for life in the Mariana trench then why not take a look at why do oceanic plates go under continental plates? or ocean facts for kids.

The second image is by 1840489pavan nd.


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