While some billionaires have been busy looking at the stars, scientists have made groundbreaking discoveries in the greatest depths of the ocean. They hold far greater wonders than the icy stretches of Mars—which we have curated for you on this happy Friday:)
Researched by: Nirmal Bhansali
Earth: The final frontier!
Yes, that was a Star Trek joke. Humans have always looked upwards—to ponder the mysteries of the universe—and to dream of conquering new worlds. But for decades, we remained greatly ignorant of what lay in the vast expanse below.
The hadal zone: That’s the name given to the darkest depths of the ocean:
The deepest parts of Earth's oceans are known as the hadal zone. Named after Hades, the Greek god of the underworld, it is a forbidding place worthy of its name. Consisting of deep trenches and troughs, it extends 11km (6.8 miles) below the surface of the world's oceans. Cumulatively they account for an area of seabed equivalent to the size of Australia.
For most of the 20th century, scientists believed this environment—“a harsh, monotonous place of perpetual darkness, frigid temperatures, limited food and extreme pressure”—makes any complex life forms impossible. In 1977, we found out otherwise—when scientists observed teeming life around hot, hydrothermal vents rising from the seafloor. That’s when we discovered something called chemosynthesis.
Wtf is chemosynthesis? Until that fateful moment, scientists had assumed that all life was created by photosynthesis—“using sunlight's energy to convert carbon dioxide and water into complex carbohydrates and oxygen.” Ergo, no sunlight, no life. That notion turned out to be entirely wrong. Living creatures in the deep sea use chemicals instead—which is called chemosynthesis.
How it works: Hydrothermal vents and ‘cold seeps’ spew fluid from beneath the Earth’s mantle. They are rich with chemicals such as hydrogen sulphide and methane. Microbes harness the energy released by these chemicals to turn carbon into food. These bacteria—eaten by tubeworms and mussels—form the base of the underwater food web.
About that water pressure: In the hadal zone, the pressure is 15,000 pounds per square inch. Living organisms have evolved at the cellular level to survive in such hostile conditions:
Creatures in the hadal zone, such as giant amphipod crustaceans and the snailfish, have enzymes called piezolytes (from the Greek "piezin" for pressure), which stop their cellular membranes and proteins from being crushed under extremely high pressure. The piezolytes counteract the pressure by increasing the space that proteins take up inside the organism's cells to counteract the weight of the water around it. "It's like putting the stakes up in a tent."
Data points to note: To this day, we have only identified 10% of the estimated two million-plus species that live underwater. And just around 25% of the seafloor has been mapped.
But as technology advances, so does our ability to plumb the depths of the ocean:
“[N]ew tools for observing, sensing and sampling the deep ocean, such as increasingly sophisticated underwater vehicles with high-definition camera systems, have demonstrated that biodiversity in the darkest depths may rival that of rain forests and tropical coral reefs.”
We can’t live underwater… so why bother?
Lol, not everything is about colonising new parts of the universe—at least, we hope not. Underwater research may be far more critical to humanity—than anything we find in the lifeless expanses of space.
One: Let’s start with space research. Conditions in the deepest parts of the ocean are remarkably similar to some of the planets in our solar system. For example:
The volcanic activity around the Lō`ihi seamount, around 30 km off the coast of Hawaii, and Gorda Ridge, 120 km off the US coast where California and Oregon meet, is thought to be similar to what may be found in the ocean worlds on Europa and Saturn's moon Enceladus.
Those are the moons of Jupiter and Saturn, respectively. There is a chance that ocean exploration may show us that Earth is not the sole example of life—even in our solar system:
[T]he discovery of chemosynthetic life on Earth and the more recent finding of perhaps 13 liquid-water oceans underneath the icy shells of moons such as Jupiter's Europa and Saturn's Enceladus—places that may have been too distant to have shared life-bearing material with Earth in the past—raise the possibility of a second, independent genesis of life. And if life can form twice in one solar system, then it could be anywhere we look in the heavens.
Whoa!! Right? Life on Earth could help us find life elsewhere in the universe.
Two: As Robin George Andrews points out in Atlas Obscura:
There is, of course, (at least) one key difference between being an astronaut and an aquanaut: Space, at least the part of it we’re able to experience, is lifeless. But every single time an aquanaut heads into the sea—either in person or using a robotic envoy—life explodes into view.
Marine life offers the unparalleled opportunity for making giant advances in human knowledge—in one fell swoop. An expedition off the coast of Chile recently discovered 100 new species!
Three: How about life-saving medicines? These newly discovered deep sea creatures may offer clues to diseases that have defied explanation or cures. For example: Alzheimer’s:
Deep-sea fish produce biomolecules called osmolytes that permit cellular functions, such as the precise folding and unfolding of proteins, to proceed unimpeded by crushing water-column pressures exceeding 15,000 pounds per square inch. Medical researchers have determined that some of these molecules could help treat Alzheimer's disease, which is characterised by misfolded proteins.
There is similar hope for cancer and other lethal diseases. The undersea world is a medical treasure trove: "Systematic searches for new drugs have shown that marine invertebrates produce more antibiotic, anti-cancer, and anti-inflammatory substances than any group of terrestrial organisms."
Four: Mining companies are eyeing the deep sea, as well. There are than 5,500 deep-sea species in the area of the Pacific Ocean known as the Clarion Clipperton Zone—which spans 1.7 million square miles of ocean—stretching from Hawaii to Mexico, and a whopping 90% of these creatures have yet to be described by science.
But, but, but: CCZ also contains one of the ocean’s largest known reserves of precious minerals—including cobalt, nickel, and manganese. They are vital to create renewable technology such as solar panels and batteries for electric vehicles—which will be critical in the fight to slow climate change.
As a result, the CCZ has become a prime candidate for potential deep-sea mining operations. Scientists are in a race to discover species—before human activity destroys them. After all, you cannot save what you do not know of.
Ok, feel free to show me awesome animals…
We have discovered and named 240,000 marine species around the world. And we’re discovering 2,200 new ones each year. Some of the biggest deep sea explorations underway right now include the following:
- The National Oceanic and Atmospheric Administration's (NOAA) is mapping the North Atlantic seafloor. It completed a six-month Voyage to the Ridge in 2022—the second in a planned series of expeditions.
- On the other side of the continent, Monterey Bay Aquarium Research Institute (MBARI), NOAA and Schmidt are mapping deep sea communities near California.
- The Schmidt Ocean Institute is mapping underwater mountains off the shores of Chile—and recently discovered 100 new species last month.
- This month, it was the turn of the Ocean Census team—who found another 100 species while exploring the Bounty Trough off the coast of New Zealand.
Point to note: In 2021, the Ministry of Earth Sciences launched our deep-ocean exploration called Samudrayaan—but it is focused entirely on finding minerals—not species. Sad.
First, to set the mood: This very cool, atmospheric vid of the deep sea world near Chile:
Okay now on to our list of all-time fave underwater creatures. FYI: They’ve been shamelessly selected for their looks.
Gummy Squirrel: which—lets face it—looks like a bizarre banana (or sex toy, just saying). The sea cucumber—discovered back in 2018 in the CCZ—earned its name thanks to the huge tail and jelly-like appearance.
Rose-veiled Fairy Wrasse: is a sly creature who is born female but turns into male—and gets its glorious colours during mating season. It is found around Maldives—130-230 feet beneath the Indian Ocean.
Snaky Siphonophore: looks like a very long millipede (up to 160 feet)—but it’s actually a giant colony of creatures. They live between 2,300 to 3,280 feet beneath the surface—and are rarely seen. The mesmerising clip below was captured by MBARI. Well, they do have a certain ASMR charm, yes?
Fluffy Sponge Crab: It is also called ‘Lamarckdromia beagle’—after Darwin’s ship HMS Beagle. This fashionista “plucks sponges and then shapes them to fit over its head and back.”
Sea Toad: We’ve featured this deep-sea anglerfish recently—but it deserves an encore. It's famous for “its gloomy expression and the glowing lure that dangles in front of its face to attract prey.” Oh, and it has an excellent party trick: It can walk! The fish was one of the 100 species discovered near Chile.
Deep-sea Batfish: was found 600 miles off the coast of Sumatra—and has already inspired poetic prose: “It sits on the seabed like an ornate pancake and struts about on two stubby fins that act as legs.” That’s besides the fishing lure on the nose to seduce unsuspecting prey. Did we mention that they look entirely goofy?
Its much hotter relative: is the Red-lipped Batfish—which is always dressed for a party. This one is found both in deep and shallow waters—near the Galapagos Islands.
Weird Sea Cucumber: Honest, that’s what scientists are calling this “bizarre deep-sea creature resembling a floating plastic bag with glowing Cheeto guts”—which was spotted near Hawaii.
A close relative: is this sea cucumber that has an excellent name: Pink See-Through Fantasia.
And the award for… the deepest-sea creature goes to this snailfish discovered in 2023 off the coast of Japan—at the greatest ever depth of 8,336 metres below the surface. That’s close to the limit that any fish can tolerate.
The bottomline: We don’t really have one. All we can say is that imagine a world where we live alongside a creature as magnificent as the Giant Phantom Jelly (see: Lead image). Wait, we already do!
Reading list
BBC News is best on why NASA is exploring deep sea worlds. Atlas Obscura has a good report on underwater volcano—while LiveScience has more on the Chile expedition. New York Times reports on the New Zealand finds. Vox is best on the threat of deep sea mining—and we did a Big Story on a global treaty that could help regulate it. Scientific American is best on why deep sea exploration matters. For more photos of recently found underwater creatures, check out The Guardian. Check out this cool website that allows you to scroll down to the deepest point on Earth.
