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Each Jason launch is a carefully choreographed dance involving engineers, technicians, pilots, and Atlantis crew members. In this video, follow along as the remotely operated vehicle is deployed from the ship for the first time during our expedition.

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Sunny
Lat: 9° 50.390 N
Long: 104° 17.490' W
Winds: E; 20.82 knots
Air Temp: 26.9°C, 80.4 °F
Bar. Pressure: 1012.1 mbar
Humidity: 69.4%
Sea surface temp: 27.4°C; 81.3 °F
Visibility: Unlimited

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Sticky Business

January 7, 2014 (posted January 8, 2014)
by David Levin

The last rays of sunlight have slipped beyond the horizon, and twilight is approaching, turning the ocean around us a murky black. For a few minutes, it stays that way—until a patch of water on the port side of the Atlantis slowly takes on a soft glow. At first, it seems like our eyes are playing tricks on us, but this is no illusion. The patch is growing. A turquoise cloud expands and shifts, builds and brightens, as it emerges from the dark of the sea. It casts an otherworldly, shimmering light, like a ghost rising from the depths.

This ghost is real. The remotely operated vehicle (ROV) Jason has returned from the bottom of the ocean, thousands of feet below us. As it rises, its bright spotlights beneath the waves create the glow.

The show doesn't last long, though, as engineers from the Jason team hoist the ROV from the water and place it onto the stern of the Atlantis. The vehicle is packed full of samples that need immediate attention.

A hint of early Earth

Special tanks inside it hold tubeworms called Alvinella that live in hot water near the vents. Nadine Le Bris' fragile sensors, used to measure chemistry and temperature at the bottom, crowd the vehicle's front basket, along with chunks of lava rock and vent chimneys. They are remnants of the world the ROV has just visited.

The pieces of chimney crumble easily and they smell of rotten eggs, because of the sulfides in the fluids that stream out of the vents. Along with the lava rock of the ocean floor, these fragile structures are some of the newest additions to the Earth's crust. But when I pick one up in my hand, I have a distinct sense that I'm holding something prehistoric, an artifact from another place and time.

In a way, I am.

"Vent sites are a lot like the early Earth," said Costa Vetriani, a microbiologist from Rutgers University. "Billions of years ago, when the planet was pretty much just oceans and volcanoes, microbes thrived. Deep-sea vents create really similar conditions."

Vetriani wants to know what makes microbes tick—how the cells survive on vent chemicals, how they first settle down on the vents, and how they grow in number.

"There are microbes everywhere on Earth,” he said, "so how do they know to pick a particular location like a vent, and how do they create a community of bacteria there?"

On this trip, Vetriani, postdoctoral scientist Donato Giovannelli, and graduate student Ashley Grosche are trying to figure that out using specially built "colonizers" that they place at the vents to attract microbes. Colonizers are simple devices—just a section of plastic pipe with a wire screen stretched over one end. Yet after only a few days on the ocean floor, they can collect a huge mass of bacteria.

Several colonizers rode along on Jason’s first dive. Now Vetriani retrieves them and finds that on every one, the screen is covered with a thick grayish slop that looks a bit like chewed up paper. This slop is called a "biofilm.” It’s similar to the slimy layer that builds up on boat hulls and toilet bowls. And it’s essential to the vent ecosystem.

Slime is good

When microbes in the deep ocean come across a good source of nutrients, like at a vent site, they tend to want to stay there. To avoid being swept away, though, they need to gain a foothold of some sort. So they start to spit out a sticky substance that anchors them to the rocks and vent structures. Gradually, this forms a slimy biofilm, a mix of microbes and their natural "glue."

"Think of it like a big fortified city of bacteria," said Giovannelli. "Once they settle down, the microbes start building up a structure they can live in safely."

Giovannelli, Vetriani, and Grosche are collecting these biofilms and preserving the bacteria inside them to study in their lab back on shore. The group will look at the genetic material of the cells to find out which microbes are settling down in the films. They will try to uncover exactly how they extract energy from vent chemicals. The researchers also want to understand how the microbes communicate with each other using chemical signals, a process called “quorum sensing.”

“Most animals communicate through chemicals, not through words,” Vetriani said. “Think about dogs—they can sniff each other out from a mile away. Bacteria can, too.”

Studying the genetic code of the microbes can also help the researchers reconstruct how the organisms evolved. If they can find genes that are common to many different forms of vent bacteria, they might be able to trace those genes back to some of the earliest life on Earth.

Doing that, they say, could help chip away at some big questions—maybe even the biggest question of them all.

“What are the origins of life on Earth? That's what drives my work,” said Vetriani. “These microbes are relics of ancient forms of life, so by studying them, we can learn a lot about where we came from.”

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