By Alaina G. Levine
There’s buried treasure beneath the sea. James Cameron isn’t looking for it, it’s not the Heart of the Ocean, and it’s not near those fabulous deep sea vents we’ve come to adore. Rather, the prize of which I write is literally under the ocean – it’s the creatures that inhabit the sediment on the floor of the world and the basement rock below.
There’s an ocean of possibilities of what types of critters might live in those environs and how they do it. It’s a huge environment, after all. 70% of the planet is covered in water and precious little of the sea’s floor and cellar rock has been explored. “We simply have no idea what’s down there,” teases Jan Amend, a University of Southern California Earth Sciences and Biological Sciences professor who is part of a new research enterprise that aims to find out what’s going on…down there.
The one and a half year old Center for Dark Energy Biosphere Investigations (C-DEBI) is a National Science Foundation-funded Science and Technology Center whose “mission is to explore life beneath the seafloor and make transformative discoveries that advance science, benefit society, and inspire people of all ages and origins.” The $25 million endeavor administratively sits at the University of Southern California, but its scientists are scattered at universities around the country including the University of Rhode Island and the University of Alaska.
This subsurface biosphere is not a new concept; in fact, in 1992, Thomas Gold argued the presence of a “deep, hot biosphere”, aided by geological energy sources. “Whitman et al.,  expanded this concept, collating available data on aquatic, soil, and subseafloor microbes, and concluded that the majority of biomass on Earth may be harbored below the surface of the Earth,” as explained on C-DEBI’s website.
But studying the dark energy biosphere is considered to be a fairly new field. The significance of C-DEBI is that it serves as a clearing house to organize collaborations, collect data and specimens, and oversee or contribute to research projects and support. For example, three missions are currently being organized by the Integrated Ocean Drilling Project (IODP), an international partnership engaged in deep-sea scientific drilling, in conjunction with C-DEBI executive committee members. “C-DEBI will seize a unique opportunity to bundle these diverse projects, to accomplish an integrated, global scientific mission,” according to its promotional materials.
Amend, who serves as C-DEBI’s Associate Director, recently took me on a mental voyage to understand the implications of the research. It is very much like “discovering a completely new world,” he says, equating it with exploring outer space. Scientists know that there are cute little microbes hanging around in those sediments, but countless questions abound. How are these organisms related to other ocean-dwelling species? What are their temperature and pressure limits? What’s their chemical and biological make-up?
He and his team are motivated to understand how distantly (or closely) related the single-celled varmints are to other life on Biosphere 1. “We expect to find branches on the tree of life that have not been seen before and are only distantly related to known species,” says Amend. Researchers will utilize methodologies such as DNA sequencing to clarify connections to other microbes on the planet.
Another particularly tantalizing query relates to the microorganisms’ energy sources. “We don’t know how they make a living down there,” he says. There’s no light, so photosynthesis is not in the picture. There’s not much organic food – “no Twinkies of hamburgers” are to be found, he jokes. So the creatures are probably relying on some sort of inorganic chemistry for survival, processing compounds like iron and sulfur for sustenance. “We’ll probably find interesting new metabolisms.” The basement rock is permeable, he explains, so fluid ebbs and flows, bringing in potential nutrients and clearing out waste products.
With more tools and better coordinated research systems in place to study the dark energy biosphere, Amend postulates that scientific and technical ramifications of C-DEBI’s findings will be game-changing. “New organisms provide a new sandbox to play in,” he hints. They may discover catalysts and enzymes with possible technological applications in myriad fields including energy, medicine, and biotech.
And there’s another potential booty to be found by digging under the ocean – scientific knowledge which could enhance our understanding of the planetary carbon cycle and climate change. We don’t know how the subsurface and surface carbon cycle is connected –yet, says Amend. The stakes are high. According to NASA, “the total amount of carbon in the ocean is about 50 times greater than the amount in the atmosphere, and is exchanged with the atmosphere on a time-scale of several hundred years. At least 1/2 of the oxygen we breathe comes from the photosynthesis of marine plants. Currently, 48% of the carbon emitted to the atmosphere by fossil fuel burning is sequestered into the ocean.”
The more we fathom what’s going on in the entire ocean, including below the water itself, the better our understanding of what’s happening to our planet. C-DEBI scientists’ findings “could have implications on lots of big ticket items like the carbon cycle and climate change,” clarifies Amend. So even though “most subsurface environments are not as sexy or dramatic as the [undersea] vents,” he jests, dark energy biosphere experts will continue their pursuit of trying to illuminate the creatures and their habitats…down there.
Alaina G. Levine is a freelance science writer, professional speaker, corporate comedian, and President of Quantum Success, a leadership and career consulting enterprise. She can be contacted through her website at www.alainalevine.com.