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... Science Frontiers ONLINE No. 14: Winter 1981 Supplement Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Worms with inside-out stomachs The recently discovered tube worms, living near the hot water vents on the ocean bottom off the Galapagos, have no mouths or guts. Their bodies are covered with thousands of feathery tentacles, each packed with blood vessels. Apparently, the tube worms extract nutrients directly from the sea water and expel wastes the same way -- having in effect external stomachs. These worms, which may be many feet long, contain enzymes that permit them to extract carbon dioxide from the seawater and fix it much like plants do during photosynthesis. George Somero, at Scripps, estimates that the enzyme levels in the worms are similar ... Science Frontiers ONLINE No. 14: Winter 1981 Supplement Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Worms with inside-out stomachs The recently discovered tube worms, living near the hot water vents on the ocean bottom off the Galapagos, have no mouths or guts. Their bodies are covered with thousands of feathery tentacles, each packed with blood vessels. Apparently, the tube worms extract nutrients directly from the sea water and expel wastes the same way -- having in effect external stomachs. These worms, which may be many feet long, contain enzymes that permit them to extract carbon dioxide from the seawater and fix it much like plants do during photosynthesis. George Somero, at Scripps, estimates that the enzyme levels in the worms are similar ...
Terms matched: 2 - Score: 288 - 15 May 2017 - URL: /sf014/sf014p08.htm
... Science Frontiers ONLINE No. 88: Jul-Aug 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Whale falls: stepping stones across the ocean abysses Unique biological communities flourish at widely separated "oases" on the deepsea floors, where hydrothermal vents supply the energy and chemicals necessary for life. Here are found free-living bacteria, tube worms, molluscs, and several other species that prosper without the benefit of photosynthesis. These chemosynthetic, thermal-vent communities are separated by thousands of kilometers of sea-floor "desert." Yet, the species involved are similar worldwide and must, at some time, have crossed these wide, forbidding expanses. One possible mechanism for this mysterious dispersion came in 1987, when the research submersible Alvin ... upon the remains of a 21-meter whale at a depth of 1,240 meters off California's coast. The whale's skeleton was covered with bacterial mats like those at the hydrothermal vents. Also sustained by the carcass were mussels, snails, and worms; all in all, a community much like those at the vents. Furthermore, many of the species partaking of the whale's energy and chemical resources are not normally found in that part of the Pacific. Subsequently, more "whale falls" with attached biological communities were found elsewhere. Calculations suggest that whale falls are more common that one might suppose -- perhaps occurring with average spacings of only 25 kilometers. They could very well be the stepping stones that allow hydrothermal vent communities to disperse across the abyssal ...
Terms matched: 2 - Score: 177 - 15 May 2017 - URL: /sf088/sf088b08.htm
... the surface of Mars than it does about the topography of the deep ocean floors. Marine biologists, however, have even more reason to feel slighted. To illustrate, the usual picture painted of the abyssal terrain beyond the continental shelves and slopes is one a a frigid biological desert -- endless plains of sterile muck, broken once in a while by oasis-like deepsea vents, where weird tube worms thrive amidst clouds of chemosynthetic bacteria. This is a highly misleading portrayal. The situation, in fact, recalls what happened when biologists first released clouds of insecticides in rain forest canopies, thus precipitating a deluge of uncataloged insects into collecting nets waiting below. Now, instead of a mere million species of insects worldwide, entomologists are thinking perhaps 10 million or more. Will the same diversity ... in the deepsea muck? C.L . Van Dover believes so: "Away from the vents, in the great ocean plains, life is much less dramatic and often scaled down to minute proportions -- threadlike worms, tiny snails, delicate, transparent clams. Yet, the diversity of animals in the cold abyssal muds, it now appears, may rival the celebrated biodiversity of the tropical rain forests." We now know virtually nothing about this fauna, how it survives, and how it evolved. Millions of undescribed species may be awaiting discovery by research submersibles and deep dredging. (Van Dover, Cindy Lee; "Depths of Ignorance," Discover, 14:37, September 1993.) Comment. Preconceptions about life and its talents have often blinded science as to the ...
Terms matched: 2 - Score: 165 - 15 May 2017 - URL: /sf090/sf090b98.htm
... Science Frontiers ONLINE No. 88: Jul-Aug 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Ship falls: supplements to whale falls?" Strange tube worms up to six feet long have been discovered off the Spanish coast, dining on the hydrogen sulphide from rotting beans [beams?] in the hold of a ship that sank 13 years ago. Lacking mouth, gut and anus, they rely on bacteria to process the nutrients in minerals and dissolved in sea water. They had been found previously in the Pacific and the Gulf of Mexico. It was thought they liked to live in huge colonies around cracks in the ocean floor where hot, mineral-rich lava pours out and areas where oil and gas leak from the seabed ... " (Anonymous; "Gas Guzzlers," Fortean Times, p. 19, no. 68, 1993. Via Daily Telegraph , June 22, 1992.) From Science Frontiers #88, JUL-AUG 1993 . 1993-2000 William R. Corliss ...
Terms matched: 2 - Score: 165 - 15 May 2017 - URL: /sf088/sf088b09.htm
... 've taken off the blinders. (Littler, Mark M., et al; "Deepest Known Planet Life Discovered on an Uncharted Seamount," Science, 227:57, 1985.) The second discovery came at 10,000 feet in the Gulf of Mexico. There, scientists in the submersible Alvin found a well-developed community of large clams, crabs, mussels, and tube worms, which closely resembles those around the Pacific hydrothermal vents. These life colonies do not use sunlight at all, nor do they depend on other life forms based on solar energy. They employ chemosynthesis, and the hydrogen sulfide and other substances in the vented waters replace sunlight. Although there are no obvious vents at the Gulf of Mexico site, the waters there contain plenty of hydrogen sulfide ... indicating seepage from somewhere. The life forms are all new to science, although they resemble those in the Pacific. (Anonymous; "Worms without Vents," Oceans, 17:50, September/October 1984.) Comment. Question: how do non-mobile life forms travel the great distances from one vent or seepage locale to another? It seems as if we are just beginning to appreciate life's colonizing capabilities. Who knows what life forms subsist in the hot geothermal fluids circulating deep in the earth's crust? From Science Frontiers #38, MAR-APR 1985 . 1985-2000 William R. Corliss ...
Terms matched: 2 - Score: 154 - 15 May 2017 - URL: /sf038/sf038p10.htm
... Sourcebook Subjects The Glow Below Is there such a thing as sunless photosynthesis? Did photosynthesis evolve at the earth's surface or deep in the oceans near hydrothermal vents? Such questions are engendered by the strength of the mysterious glow that emanates from these deep-sea vents. It is at these cracks in the ocean floor that very hot, mineralladen water gushes forth, and where colonies of bizarre tube worms, blind shrimp, and hyperthermophilic (high temperature-loving) bacteria thrive. (For details, see SF#60 or p. 238 in Science Frontiers, the book) The first anomaly is the strength of the glow itself. It is not all thermal radiation emitted by the 350 C water spewing forth from the vents; in fact, it is 19 times more intense than ... from theory. Something else is contributing energy, but no one knows what it is so far. The unexpected intensity of the vent glows also asks some provocative questions of the biologists: Is the glow strong enough to sup port photosynthesis? Quite likely, seems to be the answer. Are life forms in the vicinity of the vents employing photosynthesis? We don't know yet, but some bacteria do photosynthesize. Might not life and perhaps photo synthesis, too, have originated at the vents rather than on the planet's surface? This is an attractive possi bility, because very early in the earth's history the surface was con tinually blasted by meteorites, comets, etc. -- a very inhospitable place. The above questions are so fascinating that we might easily neglect ...
Terms matched: 2 - Score: 148 - 15 May 2017 - URL: /sf108/sf108p07.htm
... a salt diapir (a massive fingerlike intrusion 500 meters below the brine pool. The origin of some diapirs is not well-understood.) The mussels get the oxygen they require from the ordinary seawater covering the dense brine. Like the biological communities surrounding the "black smokers" and other ocean-floor seeps, the brine-filled pockmark community includes several species of shrimp, crabs, and tube worms. We have here another example of the astounding ability of lifeforms to take advantage of unusual, even bizarre niches. (MacDonald, I. Rosman, et al; "Chemosynthetic Mussels at a BrineFilled Pockmark in the Northern Gulf of Mexico," Science, 248:1096, 1990.) Comment. Such examples of life's adaptability are so common one hesitates to label them ... anomalous. Yet, one wonders how and why life acquired this property. Is the human urge to go to the planets a genetically derived extension of this urge to colonize new terri tories. From Science Frontiers #73, JAN-FEB 1991 . 1991-2000 William R. Corliss ...
Terms matched: 2 - Score: 145 - 15 May 2017 - URL: /sf073/sf073g13.htm
... in the 400 water gushing forth from deep-sea vents. We will call them "geochemical creatures" to separate them from the "photosynthetic creatures" we are more familiar with. But, in principle at least, there could also be "Carnot creatures", whose metabolisms depend upon temperature differences like almost all human-built engines. Some bizarre animal, such as a meter-long tube worm, could plant one end on a hot rock surface and dangle the other in cold seawater to reject waste heat from its Carnot engine. Since thermodynamic-cycle efficiencies can approach 60% compared with only 10% for photosynthesis, evolution would have been remiss if it had not tried to evolve "Carnot creatures." For, as D. Jones comments below, Carnot creatures would be ... to many more habitats in the universe than photosynthetic creatures, which must have a sun with a very specific electromagnetic spectrum. "Many worlds, from distant 'brown dwarf' stars to the satellites of giant planets, may have internal heating but no effective 'Sun'. If Carnot life is possible, it may well have evolved in such dark and distant places -- making life abundant throughout the Universe. Indeed, our distant descendants may be able to harness Carnot biochemistry to sustain themselves on geothermal or residual browndwarf warmth when the Sun finally grows dim." (Jones, David; "The Dark Is Light Enough," Nature, 385:301, 1997.) Comments. To our knowledge, those who search for extraterrestrial life do not consider the possibility of Carnot creatures and ...
Terms matched: 2 - Score: 143 - 15 May 2017 - URL: /sf111/sf111p08.htm
