A recent deep-sea expedition has uncovered a previously unknown ecosystem beneath the ocean floor, where communities of animals, including giant tube worms, thrive in the extreme environment below hydrothermal vents.
While these ecosystems have been studied for decades, the team made an unprecedented discovery: not only do animals thrive around the vents, but they also live beneath the seafloor, in hidden volcanic caves.
Using the remotely operated vehicle (ROV) SuBastian, the researchers drilled small holes in the seafloor rocks and flipped over sections of volcanic crust.
Unlike most ecosystems on Earth that rely on sunlight for energy, these deep-sea ecosystems depend on chemical reactions to produce energy in a process known as chemosynthesis.
This finding challenges previous assumptions that life below the seafloor was limited to microbes and viruses.
Huge tube worms and other animal communities flourish in the harsh conditions beneath hydrothermal vents in a previously undiscovered ecosystem that was discovered by a recent deep-sea expedition. Scientists investigating the East Pacific Rise made this discovery, which challenges our knowledge of marine ecosystems by showing that life is not limited to the ocean’s surface or seafloor but also extends into underground volcanic caverns.
A Secret World Underneath the Sea.
Exploring the volcanic East Pacific Rise, where two tectonic plates meet and form deep-sea hydrothermal vents, took the team 30 days on board the Schmidt Ocean Institute’s research vessel “Falkor (too)”. It is known that these vents support ecosystems that rely on chemosynthetic bacteria to turn chemicals from the vents into energy in order to survive without sunlight. The team made an unprecedented discovery despite decades of research on these ecosystems: animals not only flourish near the vents but also reside in secret volcanic caverns beneath the seafloor.
Researchers used the remotely operated vehicle (ROV) SuBastian to flip over pieces of volcanic crust and drill tiny holes in the seafloor rocks. They discovered an unexpected system of warm fluid-filled cavities beneath the rocks that were teeming with life, including enormous tube worms that could reach lengths of up to 1 to 6 feet (0 to 5 meters). Coauthor of the study and marine ecologist Dr. Monika Bright called the scene “spectacular,” stating that “there were animals, 50 centimeters long, lying in there—alive.”. “,”.
The temperature of these submerged habitats is approximately 75 degrees Fahrenheit (24 degrees Celsius), which is significantly warmer than the frigid ocean waters that surround them. By demonstrating that ecosystems above and below the seafloor are interconnected and that life forms use the seafloor’s fissures to migrate between habitats, this discovery expands the known bounds of life.
The relationship between subsurface and seafloor ecosystems.
The researchers found that the vent fluid, which transports chemicals and heat from beneath the crust of the Earth, fosters an environment that supports life below and above the seafloor. Chemosynthetic bacteria, which are supported by this fluid, give food to other species like giant tube worms, snails, and mussels. These deep-sea ecosystems use a process called chemosynthesis to create energy, as opposed to the majority of ecosystems on Earth that rely on sunlight.
According to the researchers, tube worm and other animal larvae may follow the flow of warm vent fluid through seafloor fissures and settle in subseafloor habitats. According to study coauthor Dr. Sabine Gollner, “We suspected that tubeworm larvae could use the warm vent fluid to move through underground fissures and colonize the surface vents from below. According to this finding, life in these subseafloor habitats is not isolated but rather a component of a dynamic system that involves the exchange of life forms between the deep volcanic crust and the surface.
This discovery contradicts earlier theories that suggested only bacteria and viruses could exist beneath the seafloor. We now know that these volcanic caves are home to larger, more sophisticated animals, which broadens our perspective on the possibility of life in harsh settings.
Deep-sea ecosystem research and preservation in the future.
This finding raises questions regarding the effects of deep-sea exploration and possible mining operations, even though it also creates new opportunities for studying subseafloor biospheres. Because large drilling operations could easily disturb these delicate ecosystems, the research team emphasized the significance of protecting them. “We need to protect what is living below the surface because it is an important component of the ecosystem,” Dr. Monika Bright stressed. “,”.
Additionally, the study, which was published in Nature Communications, emphasizes the possibility that life could exist in other uncharted oceanic regions—possibly even beneath other hydrothermal vents worldwide. In order to determine whether these ecosystems are widespread, the team will next look into the horizontal and vertical extent of the subseafloor caves.
