Until recently, scientists believed that the sole source of energy responsible for life on earth was the sun. In 1977, a group of scientists researching the theory of plate tectonics, traveled to the floor of the equatorial Pacific Ocean and discovered something that could possibly explain how life began on this planet. From the Galapagos Rift’s thermal springs, scientists discovered densely populated communities of several species never before observed. Since that time the Federal Government has devoted more than 10 million dollars to research these communities and their evolutionary history. This figure, to many scientist’s dismay, is dramatically less than that of the space exploration program’s budget. For example, in 1992, the government budget for oceanography research was $600 million while NASA spent 8.5 billion. We know more about the space around us than we do about our own home.
Only 1 percent of the sea floor has been mapped. The sea is the largest, most inaccessible, and least understood ecosystem on this planet. Since studies of these communities began, previous notions that cold darkness, and extreme pressure are inimical to life have been disproved. We now know that an ecosystem can be sustained by unusual energy sources.
They have been called archaea. Research on these animals is limited since they do not grow and culture well in a laboratory. These animals live in extremely hot temperatures of 160 degrees Fahrenheit and higher, while microbes have been found living in boiling water. This revelation surely must change all of the “rules” we have for health standards. These newly discovered facts must dramatically change the way we think of life on earth. Living in these vents are entire communities of invertebrates: tube worms, mussels, clams, and even shrimp. In the absence of light and without the photosynthesizing plankton that provide most sea life with food, these animals have an alternate way to live. These invertebrates have formed symbiotic relationships with the bacteria living with them. The mechanics of this relationship are incredibly interesting. Bacteria thrive on sulfide which is found in vent water (hydrogen sulfide).
They use the sulfide’s chemical energy to produce organic carbon compounds similar to how plants use solar energy in photosynthesis. The bacteria employ chemical rather than light energy to transform inorganic carbon to organic compounds. This process is called chemosynthesis, and was at first thought to be a rare phenomenon. The invertebrate houses the bacteria and provides chemicals needed for the process of chemosynthesis. The bacteria in turn gives organic carbon compounds to the invertebrate, which keeps the invertebrate alive, (so it expends little or no energy gathering its own food). An example of this type of tubeworm can be found in vents along submarine mountain ranges off of the western coasts of Mexico and South America.
One in particular, at a site called the Rose Garden in the Galapagos Rift is long and white with a luminous red plume. Upon examination it was discovered that these worms have no mouth, stomach, or digestive system. They survive by extending their plume into the vent fluids absorbing numerous compounds including sulfide which are turned over to the bacteria. The bacteria then provide food to their host. The existence of this symbiotic relationship between an invertebrate and a bacteria is as incredible as their existence. Another feature of this relationship is their mutual dependence on oxygen. Oxygen is an element required by the vent bacteria to perform its essential role. Interestingly, this is one of the few ways these communities are tied to the world away from the vent. The implications of this awesome discovery are providing us with leads, clues, and suggestions to where life began and where it is going.
From biotechnology that can be used in tracing fingerprints in a crime scene, to discovering where life begun, this great new breakthrough will immensely enhance our understanding and comprehension of our life and our environment. We do not yet know where this new information will lead us, as our knowledge as well as our funding and perhaps even our imagination is limited. We once thought the earth was flat, ancient man thought that lightning was from an angry g-d, and until recently scientists thought that life without sunlight at the bottom of the ocean was impossible, so we are left with an incredibly complex universe to study, starting with our planet.
“Clues to Fiery Origin of LIfe Sought in Hothouse MIcrobes” by William J. Broad The New York Times May 09, 1995 V144, pB7(N), pC1(L), col 5, (48 col in.). “Depths of Ignorance” by Cindy Lee Van Dover. Discover September 1993 V14, n9, p. 37(3). “Hydrothermal-Vent Communities of the Deep Sea” by Verena Tunnicliffe American Scientist July/August 1992 V80, n4, p.336(14).