Until recently, scientists believed that the sole source ofenergy responsible for life on earth was the sun. In 1977, agroup of scientists researching the theory of plate tectonics,traveled to the floor of the equatorial Pacific Ocean anddiscovered something that could possibly explain how lifebegan on this planet.
From the Galapagos Rift’s thermalsprings, scientists discovered densely populated communities ofseveral species never before observed. Since that time theFederal Government has devoted more than 10 million dollarsto research these communities and their evolutionary history. This figure, to many scientist’s dismay, is dramatically lessthan that of the space exploration program’s budget. Forexample, in 1992, the government budget for oceanographyresearch was $600 million while NASA spent 8. 5 billion.
We knowmore about the space around us than we do about our ownhome. Only 1 percent of the sea floor has been mapped. The seais the largest, most inaccessible, and least understoodecosystem on this planet. Since studies of these communities began, previous notionsthat cold darkness, and extreme pressure are inimical to lifehave been disproved. We now know that an ecosystem can besustained by unusual energy sources.
The animals that havebeen discovered in hydrothermal vents are fascinating as wellas extremely important. The structure of these creatures issuch that a new kingdom has been discovered/created. Previously scientists divided the living world into twokingdoms: bacteria, also known as prokaryote andeukaryotes (plants and animals). The difference between thetwo kingdoms was their genetics. The DNA of these newlydiscovered animals was distinct from the two other kingdoms. They have been called archaea.
Research on these animals islimited since they do not grow and culture well in alaboratory. These animals live in extremely hot temperaturesof 160 degrees Fahrenheit and higher, while microbes have beenfound living in boiling water. This revelation surely mustchange all of the “rules” we have for health standards. Thesenewly discovered facts must dramatically change the way wethink of life on earth. Living in these vents are entire communities ofinvertebrates: tube worms, mussels, clams, and even shrimp. Inthe absence of light and without the photosynthesizingplankton that provide most sea life with food, these animalshave an alternate way to live.
These invertebrates haveformed symbiotic relationships with the bacteria living withthem. The mechanics of this relationship are incrediblyinteresting. Bacteria thrive on sulfide which is found in ventwater (hydrogen sulfide). They use the sulfide’s chemical energyto produce organic carbon compounds similar to how plantsuse solar energy in photosynthesis. The bacteria employchemical rather than light energy to transform inorganiccarbon to organic compounds.
This process is calledchemosynthesis, and was at first thought to be a rarephenomenon. The invertebrate houses the bacteria andprovides chemicals needed for the process of chemosynthesis. The bacteria in turn gives organic carbon compounds to theinvertebrate, which keeps the invertebrate alive, (so it expendslittle or no energy gathering its own food). An example of thistype of tubeworm can be found in vents along submarinemountain ranges off of the western coasts of Mexico andSouth America. One in particular, at a site called the RoseGarden in the Galapagos Rift is long and white with a luminousred plume.
Upon examination it was discovered that theseworms have no mouth, stomach, or digestive system. Theysurvive by extending their plume into the vent fluids absorbingnumerous compounds including sulfide which are turned overto the bacteria. The bacteria then provide food to their host. The existence of this symbiotic relationship between aninvertebrate and a bacteria is as incredible as their existence. Another feature of this relationship is their mutual dependenceon oxygen. Oxygen is an element required by the vent bacteriato perform its essential role.
Interestingly, this is one of thefew ways these communities are tied to the world away fromthe vent. The implications of this awesome discovery are providingus with leads, clues, and suggestions to where life began andwhere it is going. From biotechnology that can be used intracing fingerprints in a crime scene, to discovering where lifebegun, this great new breakthrough will immensely enhanceour understanding and comprehension of our life and ourenvironment. We do not yet know where this new informationwill lead us, as our knowledge as well as our funding andperhaps even our imagination is limited.
We once thought theearth was flat, ancient man thought that lightning was froman angry g-d, and until recently scientists thought that lifewithout sunlight at the bottom of the ocean was impossible, sowe are left with an incredibly complex universe to study,starting with our planet. REFERENCES”Clues to Fiery Origin of LIfe Sought in Hothouse MIcrobes” by William J. BroadThe New York TimesMay 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” byVerena Tunnicliffe American Scientist July/August 1992V80, n4, p.336(14).Words/ Pages : 887 / 24
