‘Extreme limits’: China-led mission finds thriving oasis in Earth’s deepest reaches
Month-long Pacific expedition uncovers vast colonies of exotic creatures oblivious to sunlight drawing energy from hidden sources
In the crushing darkness of the northwest Pacific Ocean, a China-led deep-sea expedition has pulled back the curtain on the deepest live habitat ever known to exist: thriving colonies of tubeworms and molluscs.
The improbable hidden oasis of life – in numbing waters up to 9,500 metres (31,150 feet) deep – synthesises energy by feasting on chemicals such as hydrogen sulphide and methane that seep out of faults in the tectonic plate.
The remarkable creatures have bypassed the need for sunlight. Instead of photosynthesis, they obtain energy from chemical reactions. The researchers have found that the methane used by the colonies is made through microbial processes in organic matter found in the sediments.
Scientists from China, Denmark, New Zealand and Russia reported their “discovery of the deepest and the most extensive chemosynthesis-based communities known to exist on Earth” in an article published in the peer-reviewed journal Nature on Wednesday.
“Given geological similarities with other hadal [deepest] trenches, such chemosynthesis-based communities might be more widespread than previously anticipated,” they wrote.
“These findings challenge current models of life at extreme limits and carbon cycling in the deep ocean.”