Strange vent-fellows: Chemosynthetic shrimp, tubeworms together for first time at hydrothermal vent

"On the very first ROV, or remotely-operated vehicle, dive, we observed abundant shrimp of a species different in appearance from other Mid-Atlantic Ridge species," said Professor Paul Tyler, Ph.D., a marine biologist from the University of Southampton in the United Kingdom who was aboard Okeanos Explorer. "These shrimp had characteristics previously seen only on shrimp containing chemosynthetic bacteria, and we identified them as such."

"During the ROV's second dive, we were witness to the first discovery of a live hydrothermal tubeworm in the Atlantic," said expedition Science Lead Chris German, Ph.D., chief scientist for the National Deep Submergence Facility at the Woods Hole Oceanographic Institution in Massachusetts. "I will take that home as my personal key discovery moment for the cruise."

The two discoveries blended into what German described as an even more remarkable discovery. "Not only did we see extensive tube worm communities of differing sizes and shapes across the length and breadth of a large hydrothermal vent field, but we observed for the first time anywhere, chemosynthetic shrimp and tubeworms inhabiting the same hydrothermal site," he said.

"The significance of these observations is that the iconic symbol of Pacific vents is the tubeworm, while the iconic symbol of Atlantic vents is the vent shrimp," added Tyler. "To find both together has important implications for the evolution of vent communities in the Caribbean as the Atlantic became separated from the Pacific some five million years ago."

Chemosynthetic tubeworms and shrimp are unlike most other life on Earth that are photosynthetic -- relying on energy from the sun. These new hydrothermal animals, by contrast, exist on the deep and dark ocean floor where no sunlight penetrates. They derive energy instead, from chemicals that rise in the hot water of hydrothermal vents making them chemosynthetic.

Tubeworms rising six feet from the seafloor were first discovered in 1977 next to hydrothermal vents in Pacific waters at the Galapagos near where the underwater tectonic plates spread. Since then, smaller tubeworms have been found at seafloor cold seeps in the Gulf of Mexico, but until this discovery, have not been observed at vents in the Atlantic.

The expedition team used a new model of telepresence-enabled ocean exploration. Few scientists and a larger number of technicians were aboard the ship, however most of the scientists were on watch or on call ashore at a network of Exploration Command Centers that are connected to the ship's sensors, systems and people in near-real time by satellite and high-speed Internet. Scientists ashore participated from centers at the University of Rhode Island and Woods Hole, and other scientists in California, Pennsylvania, Germany, Canada, Portugal and the United Kingdom participated via live video feeds and some through online instant messaging. They played a key role by identifying biological, chemical and geological features shown in ROV images or revealed in data from ocean sensors thousands of miles away.