A study published Wednesday in Nature described the deepest and most extensive chemosynthesis-based communities ever recorded, where thousands of tube-shaped animals rose from the seabed, reported the Los Angeles Times.
The international team conducted 23 dives in the western Pacific with the Chinese submersible HOV Fendouzhe; thriving chemosynthetic life appeared during 19 of them, wrote T-Online. Scinexx noted that the densest colonies occupied depths reaching 9,533 meters and stretched along the trench floor for roughly 2,500 kilometers.
Video captured tube worms up to 30 centimeters long among clams, mussels, bristle worms, and sea snails. Laboratory tests showed methane-rich, biogenic fluids seeping through deep faults, providing the chemical energy that replaced sunlight. Mussels hosted chemoautotrophic symbionts, while tube worms fed on microbial by-products or small prey.
Researchers measured as many as 5,813 tube worms and 293 mussels per square meter, densities that forced a revision of earlier maps of hadal biology, according to Scinexx.
“Look how many there are, look how deep they are. They don't all look the same, and they're in a place that we haven't had good access to before,” said Julie Huber, a deep-sea microbiologist at Woods Hole Oceanographic Institution, according to the Los Angeles Times.
“Their existence challenges long-standing assumptions about the potential for life at extreme depths,” said Mengran Du of the Chinese Academy of Sciences and Vladimir Mordukhovich of the Russian Academy of Sciences, according to the Los Angeles Times.
“With this discovery, future studies will focus on how these deep-sea creatures adapted to survive in such extreme conditions and how exactly they harness chemical reactions for food,” said Du and Mordukhovich, according to the New York Post.
Scientists and environmental groups fear deep-sea mining could destroy the newly documented ecosystems, which lie within and around the Mariana Trench that plunges to about 11,000 meters.
Earlier sediment samples failed to detect these colonies, suggesting that the deep ocean hosts far more chemical-powered life than previously assumed, while policymakers continue to weigh mineral extraction against ecological risk.
The preparation of this article relied on a news-analysis system.