The study, published on October 15 in the journal Nature Communications, marks a groundbreaking discovery of animals in fluid-filled cavities beneath deep-sea vents.

For the first time, scientists have uncovered a diverse ecosystem of animal life thriving beneath the seafloor, challenging previous assumptions that only microbes could survive in such extreme environments.

An expedition to a volcanically active ridge in the Pacific Ocean off the coast of South America revealed various creatures, including giant tubeworms, snails, and polychaete worms, living near underwater hot springs.

Using the remotely operated vehicle SuBastian aboard the research vessel Falkor, scientists explored depths of 8,250 feet (2,515 meters) and discovered adult tube worms in hydrothermal fluid-filled pockets.

Some of the tubeworms found were over 16 inches (41 cm) long, indicating that these cavities are not merely nurseries but host adult organisms that rely on bacteria for nutrition.

The presence of both male and female Riftia pachyptila in these cavities suggests that reproduction is occurring beneath the seafloor.

Study co-author Sabine Gollner noted that young animals from above the seafloor may be traveling through the vents to settle in deeper areas, indicating a complex life cycle.

These findings are significant for astrobiology, as they suggest that similar life forms could exist in extreme environments on other planets and moons, such as Jupiter's icy moons.

The urgency for protecting deep-sea habitats is emphasized, especially given potential threats from deep-sea mining operations targeting mineral-rich areas.

Hydrothermal vents are formed in volcanically active areas where seawater interacts with magma, producing mineral-rich fluids that support symbiotic animal and microbial life.

Future research is planned to explore the existence of similar animal colonies below other hydrothermal vents globally, expanding our understanding of these unique ecosystems.

Co-author Sabine Gollner expressed surprise at the unexpected findings, highlighting the need for further exploration of the subseafloor biosphere.