It’s believed that the depths of the oceans are home to millions of fascinating lifeforms which we actually know nothing about. That’s because their harsh environment is extremely difficult for scientists to study. But advances in technology mean that researchers are able to send sophisticated machines to these previously unexplored locations. With that in mind, a group of scientists deployed an unmanned submarine 3 miles beneath the surface of the Pacific Ocean, and what they found was absolutely extraordinary.
The incredible find was made in an area known as the Clarion Clipperton Zone (CCZ). This huge slice of the Pacific Ocean is situated between Mexico and Hawaii and it spans a colossal 1.7 million square miles. This huge expanse is as wide as the continental United States and larger than the entire country of India. And it’s also a figurative goldmine, according to some.
Explorers don’t believe that there’s actual gold in the CCZ, but they reckon it contains other rare Earth metals that could total billions of dollars in value. As a result, deep sea mining corporations are currently scouring the area – hoping to turn up riches by combing through the so-called polymetallic nodules that line the seafloor.
These nodules can be found across the planet’s oceans – usually forming either on or just beneath the seabed. They’re comprised of manganese oxides and precipitated iron oxyhydroxides, which act as a magnet for metals and elements such as cobalt, titanium and copper. And that makes them incredibly appealing to mining corporations.
The metals that appear in these polymetallic nodules are apparently critical to the needs of modern society. For instance, they’re required to support the development of new technology, the move towards increased urbanization and research into a green-energy economy. However, this new era of mining also presents potential challenges and risks.
The International Seabed Authority (ISA) has marked out nine so-called Areas of Particular Environmental Interest (APEIs) across the CCZ, and these are off-limits to mining corporations. These areas span nearly 62,000 square miles and have been designated in order to protect the fascinating sea life within the CCZ.
The APEIs take into account the animals’ habitats, availability of food, the coverage of the nodules and even the topography of the seafloor. Yet some scientists are concerned that these measures may not go far enough, and that any mining ventures could still have detrimental effects on the seabed. For one, the polymetallic nodules take millions of years to form and cannot be replaced in any effective way.
What’s more, scientists are really only beginning to explore the rich diversity of life across the CCZ. Extensive further studies are required to truly understand their populations and the full impact that any mining operations may have. As a result, the scientific community is largely in agreement that the ISA should forbid mining across a third of the CCZ and implement strict rules where the process is allowed.
The ISA has consequently awarded exploration contracts on the basis that the mining companies carry out environmental studies of their territory. As a result, a whole host of different countries and organizations have initiated a comprehensive research effort across the CCZ. And some of these surveys have discovered incredible new species living near the seafloor.
One such research project combined the collective talents of scientists from the University of Geneva, the University of Hawaii and the U.K.’s National Oceanography Centre. In 2018 the team used a remotely operated vehicle (ROV) from the University of Hawaii to explore the western CCZ – collecting samples from the seabed. And extensive analysis of those samples revealed two years later that the scientists had discovered an astonishing, alien-like species living in the CCZ.
Most of the ocean life we’re familiar with dwells in the upper zones of the sea, where sunlight is readily available. Though these species actually represent a tiny fraction of the full extent of genera that live beneath the surface. Below 650 feet – where the light begins to disappear – the environment grows colder and harsher, but it’s still teeming with life.
The deepest pockets of the ocean are mostly unexplored, but it’s thought that they’re home to around a quarter of the 8.7 million species that inhabit the Earth, according to PLOS Biology. Of those, some 91 percent remain undiscovered or undescribed and still need to be catalogued by scientists. But the few species we have found have provided incredible insights into how life has adapted to survive in the unforgiving depths of the sea.
At 2.5 miles deep, Sailors for the Sea notes that the ocean’s pressure is equivalent to approximately 400 times that on the surface. As a result, there’s a very low density of organisms in the deep ocean, which presents innumerable challenges for the species that dwell there. For instance, life forms have been forced to adapt to the relative scarcity of food.
Take the Anoplogaster cornuta – or “fangtooth” – which has teeth so huge that its mouth can barely close. In the absence of light, those dagger-like fangs allow it to lunge at the rare prey it comes across. Deep below the Atlantic Ocean, meanwhile, you’ll find a species of deepwater worm that’s developed exceptionally long lips –giving it a similar evolutionary advantage in a limited habitat.
Finding a mate can also be tricky at these extreme depths. However, some animals have unique solutions to this particular problem. The deep-sea anglerfish, for instance, will use its teeth to latch onto a potential partner. According to Sailors for the Sea, “… [The male] will bite onto the female, their blood vessels fuse, and he will spend the rest of his life as a sperm producing appendage.”
But it’s not just a lack of food and mates that’s problematic; the pressure can create more direct problems for deep sea creatures, too. After all, the intense atmosphere would likely crush most surface-dwelling beings. But life on the seafloor has adapted. An ugly creature known as a blobfish has a density lower than water – allowing it to survive the crushing pressure.
The Sun then disappears altogether at around 1,000 meters beneath the surface of the ocean, according to Marine Bio. But the waters aren’t completely absent of light here. The website adds that many species are capable of bioluminescence – a type of chemical reaction that provides a small amount of light. Scientists believe that this ability can help these organisms attract prey, resist predators, navigate the oceans and even attract mates.
Some deep-sea animals create this bioluminescence through photophores – a type of organ that produces light. The lanternfish, for instance, has rows of these tissues along its body, and the pattern varies between sex and species. Not all organisms have photophores, though. For instance, the Swima bombiviridis – or swimming green bomb – apparently drops luminous green “bombs” to distract potential predators.
Generally, fish in the deep oceans measure just 6 inches long at most, according to Sailors for the Sea. But it’s a different story altogether for invertebrate organisms. Indeed, they can grow to enormous sizes. The website claims that the largest known deep-sea squid reached a whopping 59 feet long. Scientists believe this marine gigantism may be caused by slow metabolism and delayed sexual maturity – leading to a longer lifespan.
Exploring the deepest parts of the ocean has proven problematic for scientists in the past. However, advancements in technology are gradually allowing humanity to learn more about these mysterious environments and the creatures that live there. More specifically, data collection devices have allowed us to not only observe deep sea life, but also collect biological samples from the seabed.
For instance, low-light cameras can be temporarily dropped into deep-sea locations or permanently installed on subsea stations. And unmanned vessels known as remotely operated vehicles (ROVs) can be used to explore areas where human divers can’t reach. These machines transmit data using cables and are usually fitted with mechanical tools for collecting samples.
Meanwhile, researchers from the U.K.’s National Oceanography Centre, the University of Hawaii and the University of Geneva would go on to use their own ROV. Specifically, they deployed a vehicle called “Lu’ukai” in an area of the western CCZ that’s more than 3 miles deep. And their expedition turned up something that seems almost out of this world.
In fact, the scientists discovered four new species of enormous, single-celled organisms known as xenophyophores. These protozoans – creatures without organs or tissue – are part of a group referred to as foraminifera, which were first described back in the 5th century B.C. Apparently, the Greek writer Herodotus observed a type of foraminifer in the limestone that makes up the Egyptian pyramids.
But Herodotus’ record was a mere mention of one form of foraminifera. It actually wasn’t until the 19th century that French scientist Alcide Dessalines d’ Orbigny first properly classified the group. Yet even now, we know very little about these strange organisms; our knowledge of xenophyophores is limited primarily because they dwell so deeply in the ocean.
These mysterious creatures can be found in almost every sea on the planet with the sole exception of the Arctic Ocean. And they’ve been observed as deeply as the Mariana Trench at an astonishing 6 miles below the surface, according to the blog All Things Considered. Their name translates to “bearer of foreign bodies” – an accurate descriptor for the giant amoebas, which live in sediment shells known as “tests.”
The remarkable organisms construct these tests from particles in their environment. And they’re surprisingly elaborate assemblies; the website SciTechDaily.com claims that they sometimes reach more than 4 inches in size. One particularly huge xenophyophore’s test was spotted in the Mid-Atlantic Ridge – deep beneath the Atlantic Ocean – and it spanned almost 8 inches. But there’s seemingly no consensus among the scientific community regarding the actual size of the organism within these shells.
Xenophyophores are also notable for how fundamental they are to the ecology of their surrounding environment. The sea floor is rich with the organisms, and any cluster of them usually signals an area of animal diversity. In fact, they apparently act as both habitats and food for deep-sea creatures such as crustaceans, worms and sea urchins, according to All Things Considered.
The scientists operating Lu’ukai used the vehicle’s manipulator arm to scoop up samples of xenophyophores in the CCZ in 2018. They then transported the organisms to the laboratory aboard their primary expedition vessel, where the samples were photographed and frozen for preservation. Finally, they were sent to a laboratory at the University of Geneva for further analysis.
The research team kept the specimens as intact as possible – choosing to only dissect fragments of each xenophyophore. The experts then extracted DNA from each of the samples in order to analyze the organisms’ morphology and genetics. And that’s when the researchers realized that they had something ground-breaking on their hands. Yes, they’d discovered four hitherto unknown species of the strange creatures.
The four new species belong to three distinct genera, two of which are also brand new to the scientific community. One of these new genera has been named Moanammina, while the researchers termed the other Abyssalia. The study’s lead author Andrew Gooday explained to the University of Hawaii at Manoa’s website in June 2020, “It seemed appropriate to name one after Moana – a Hawaiian word meaning ocean.”
The naming of Abyssalia was equally appropriate – paying homage to the location from which the scientists collected the samples. Gooday continued, “Xenophyophores are one of the most common types of large organism found on the CCZ abyssal plains, so the name of the second genus was chosen to reflect this.”
The new species within the Moanammina genus – Moanammina semicircularis – has a stalked test that resembles a fan and is roughly 3 inches in height and width. The two species within the Abylissa genus, meanwhile, both have shells constructed from the building blocks of “glass sponges” – a type of deep-sea animal. Where one is spherical, though, the other is shaped like a flat leaf.
The fourth and final new species – Psammina tenuis – belongs to a known genus, and has a thin, delicate shell. The number of described xenophyophores in the CCZ has now reached 17 following the discovery of these news organisms. According to Gooday, that’s roughly 22 percent of the worldwide total for this particular group of amoebas.
However, that number represents just a fraction of the xenophyophores that occupy oceans all over the world. And scientists do actually know about many more in the CCZ alone – they just haven’t been analyzed and described. Gooday told the University of Hawaii at Manoa, “This part of the Pacific Ocean is clearly a hotspot of xenophyophore diversity.”
Oceanographer and chief scientist on the expedition Craig Smith also reinforced Gooday’s conclusion. He added in June 2020, “The abundance and diversity of these giant single-celled organisms is truly amazing! We see them everywhere on the seafloor in many different shapes and sizes. They clearly are very important members of the rich biological communities living in the CCZ.”
Smith went on to further underline the importance of xenophyophores to the CCZ’s biodiversity. He said, “Among other things, they provide microhabitats and potential food sources for other organisms. We need to learn much more about the ecology these weird protozoans if we wish to fully understand how seafloor mining might impact these seafloor communities.”
The new species haven’t just told the scientists more about the conditions in the CCZ, however. One of them has also revealed more about the nature of these mysterious organisms themselves. Moanammina semicircularis shares its genetic makeup with a specimen collected from the eastern CCZ in 2017. This study is therefore the first confirmation that individual xenophyophore species are not confined to a single area.
What’s more, the scientists believe that they may have even discovered a fifth brand new species of xenophyophore. The organism was reportedly spherical and has been described as a “mudball.” Though the delicate consistency of the creature sadly meant that it had completely disintegrated before the researchers could confirm whether it really was a new species.
The scientists published their findings in the August 2020 volume of the European Journal of Protistology following lengthy analysis of the xenophyophores that did survive the journey to Geneva. They also included photographs of each xenophyophore, along with comprehensive data covering precisely when and where in the CCZ each sample was collected.
Nevertheless, we remain relatively in the dark about much of life in the deep sea – despite this monumental discovery. But scientists are gradually beginning to explore more of these unknown underwater regions, and in turn, they’re finding more of these fascinating creatures. And every encounter brings us one step closer to understanding the true breadth and depth of life on our planet.