A team of scientists exploring an underwater volcano have discovered that life below the seafloor is more thriving than we could have ever imagined.

In a new article published in the scientific journal Nature Communications, the team explain that below the deepest parts of our ocean lies a whole undiscovered ecosystem of animals, including the giant tubeworm, flourishing in the unique environment found there:

“It was once believed that only microbes and viruses inhabited the subseafloor crust beneath hydrothermal vents. Yet, on the seafloor, animals like the giant tubeworm Riftia pachyptila thrive.”

Their discovery, which has shaken previous concepts of life on the sea floor, was made amongst the numerous volcanic vents found at the East Pacific Rise, off the coast of South America.

Among the other animals found in the area immediately surrounding the volcanic vents were other kinds of worms and snails, refuting previous suggestions that only microbes and viruses would be able to survive in what was previously thought to be a thoroughly inhospitable aquatic environment.

In a method not uncommon to those among us who have lifted a rock in the garden and peered at the tiny life forms living underneath, the team used an underwater robot to lift slabs of deep-sea rock. Underneath the vents, this technique revealed the previously undiscovered deep-sea critters: a game-changer for our knowledge of life under the oceans, as the article continues:

“The discovery of animal life beneath the surface of the Earth’s crust raises questions concerning the extent of these ecosystems, which is larger than what can be seen on the seafloor surface.”

Moreover, this discovery has led the team to research the cycles that allow life to survive under the volcanic ridges, with their findings deepening scientific understanding of these underwater vents as vital and wholly functional underwater ecosystems.

In fact, the movement and heat coming from the vents are vital to the life cycles of these creatures.  As well as being a habitat, these vents are crucial to the species’ survival, allowing their larva to be dispersed and their cycles to continue, with benefits beyond their own ecosystems too:

“Their larvae are thought to disperse in the water column, despite never being observed there. We hypothesized that these larvae travel through the subseafloor via vent fluids. In our exploration, lifting lobate lava shelves revealed adult tubeworms and other vent animals in subseafloor cavities. The discovery of vent endemic animals below the visible seafloor shows that the seafloor and subseafloor faunal communities are connected. The presence of adult tubeworms suggests larval dispersal through the recharge zone of the hydrothermal circulation system.”

Why is this discovery important?

Well the more we know about the ecosystems in every corner and hidden depth of our planet, the better. Even the tiniest organisms are crucial in the giant ecosystem that is our planet, and these creatures are no exception. In fact, they are part of a system that produce oxygen and reduce carbon, playing a tiny but important role in our fight against climate change, and keeping our planet safe and habitable far into the future.

With this in mind, the team’s message is clear. We may have only just discovered these otherworldly creatures, but now we know about them, their protection is vital:

“Given that many of these animals are host to dense bacterial communities that oxidize reduced chemicals and fix carbon, the extension of animal habitats into the subseafloor has implications for local and regional geochemical flux measurements. These findings underscore the need for protecting vents, as the extent of these habitats has yet to be fully ascertained.”

And what are we protecting them from?

Like many of the flora and fauna on our planet, it is imperative that we protect them from damage from human interaction. The scientists outline one particular threat to the existence of these creatures – deep sea mining – and warn that this damaging process could be detrimental to these species, having domino-effect ramifications on other creatures within greater ecosystems as a result:

“The uniqueness of active hydrothermal vents is well recognized, and protection against potential future anthropogenic impact such as deep-sea mining has been suggested or is in place. The discovery of animal habitats in the crustal subseafloor, the extent of which is currently unknown, increases the urgency of such protections.”

Though they admit that their research really only scratches the surface of the life that exists on and below the sea floor, the team are hopeful that their research will contribute to much bigger things:

“The study of the subseafloor biosphere for animal life has just begun. These efforts will lead to a better understanding of hydrothermal vent biogeochemistry, ecology, and evolution and its impact on global biodiversity, and connectivity, potentially leading to better management of seafloor surface and crustal subseafloor hydrothermal vents.”

After all, this is only a couple of vents from one deep sea volcanic ridge.

With so much more ocean to explore, the real question is: what else is out there?

If you thought that was interesting, you might like to read about why we should be worried about the leak in the bottom of the ocean.