118 results found.
... 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 chanced 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 ...
Terms matched: 1 - Score: 15 - 15 May 2017 - URL: /sf088/sf088b08.htm
... Science Frontiers ONLINE No. 80: Mar-Apr 1992 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Dinosaur Flatulence And Climate Changes "Fossilized dinosaur dung contains evidence that flatulence from the giant creatures may have helped warm the Earth's climate millions of years ago, scientists said yesterday. "The researchers detected chemical signs of bacteria and algae in known and suspected dinosaur droppings. That indicates that plant-eating dinosaurs digested their food by fermenting it, a process that gives off methane." We all know that methane is a "greenhouse gas," so it seems that the dinosaurs may have self-destructed. (Anonymous; "How Dinosaurs May Have Helped Make Earth Warmer," San Francisco Chronicle, October 23, 1991. Cr. D.H . Palmer) Comment. We are not being facetious here, for it is seriously proposed that much of the greenhouse gas produced today comes from cattle, sheep, and other animals that ferment their food. From Science Frontiers #80, MAR-APR 1992 . 1992-2000 William R. Corliss ...
Terms matched: 1 - Score: 15 - 15 May 2017 - URL: /sf080/sf080g12.htm
... Science Frontiers ONLINE No. 84: Nov-Dec 1992 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects It Came From Within Life did, that is! Forget that warm little pond where life incubated according to all the textbooks. Instead, says T. Gold, an iconoclastic Cornell physicist, life began in rocky fissures deep down in the earth's crust. The idea is not as unlikely as it sounds. Look at the most primitive life forms we know, the archaebacteria. They like heat, need neither air nor sunlight, and prosper on sulfur compounds for sustenance. Such bacteria are today found in boreholes as deep as 500 meters, in thermal springs, and around deepsea vents. Gold surmises that these archaebacteria migrated to the surface long ago, where they evolved into higher forms of life. "Gold argues, moreover, that the earth's interior would have provided a much more hospitable environment for proto-life four billion years ago than the surface would have, ravaged as it was by asteroids and cosmic radiation. And if life emerged within the earth, then why not within other planets? 'Deep, chemically supplied life,' Gold says, 'may be very common in the universe.'" (Horgan, John; "It Came from Within," Scientific American, 267:20, September 1992.) From Science Frontiers #84, NOV-DEC 1992 . 1992-2000 William R. Corliss ...
Terms matched: 1 - Score: 15 - 15 May 2017 - URL: /sf084/sf084b05.htm
... Science Frontiers ONLINE No. 90: Nov-Dec 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Depths Of Ignorance Oceanographers have been heard to complain that science knows more about 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 prevail 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 ...
Terms matched: 1 - Score: 14 - 15 May 2017 - URL: /sf090/sf090b98.htm
... Science Frontiers ONLINE No. 84: Nov-Dec 1992 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The Hunt For The Magnetoreceptor When magnetite particles were found in organisms from bacteria to bats, it was assumed that here was the long sought magnetoreceptor which animals used for magnetic navigation. But so far, biologists do not have the slightest notion how such magnetite particles can be turned into a "magnetic sense," which sends the brain information on the direction of the geomagnetic field or, perhaps, draws a magnetic map of sorts. A completely different sort of magnetreceptor is now under investigation, one that humans may also unknowingly possess. It utilizes special photoreceptors that employ an electron-spin resonance process which is modulated by the geomagnetic field. Some of our very sensitive magnetometers use similar phenomena. The biological version of such a receptor would be connected to the brain, as the eye is, and send signals as to the direction of the earth's magnetic field. Sounds interesting, but is there any basis for thinking such a sophisticated gadget could have evolved? It seems that some experiments with newts by J.B . Phillips and S.C . Borland support the idea. The newts were first trained to orient themselves in a certain direction with respect to the geomagnetic field. "When tested under one of four artificial field alignments (magnetic north at geographic north, east, south or west), the newts kept their training directions constant relative to the magnetic rather than the geographic system of reference, but they selected ...
Terms matched: 1 - Score: 14 - 15 May 2017 - URL: /sf084/sf084b99.htm
... . The expected boundary (" suture") between two old tectonic plates thought to exist at 3 km according to surface geology had not yet appeared at 7.5 km. Most interestingly, crevicular structure (crevices and pores) existed at almost all depths, even though theory said they could not because of intense pressures. And these voids were filled with fluids. P. Keher, a KTB scientist, was amazed at what the drill found: "When I started 25 years ago, the idea was that the deeper you go into the crust, the drier it gets." (Kerr, Richard A.; "Looking -- Deeply -- into the Earth's Crust in Europe," Science, 261:295, 1993.) Comment. Deep-living bacteria were not mentioned in the above article, but Soviet scientists claim to have pumped them up from 12 km down! Outer space may not be our final frontier despite the introductory blurb to Star Trek! From Science Frontiers #90, NOV-DEC 1993 . 1993-2000 William R. Corliss ...
Terms matched: 1 - Score: 13 - 15 May 2017 - URL: /sf090/sf090g08.htm
... -swallowing leviathan. (Griffin, D.J .G ., and Yaldwyn, J.C .; "Giant Colonies of Pelagic Tunicates..," Nature, 226:464, 1970) Slime molds. Moving down life's ladder to even smaller and simpler organisms, some amoebas have a bizarre life cycle that ends as a superorganism called a "slime mold." If you viewed an amoeba through the microscope in biology lab, you know that they are very tiny, very simple, and most certainly not very bright. But given enough food, some species of amoeba divide and keep dividing until they clump together in a "slug" that sends out streamers and sort of flows along the surface. We now have a mobile superorganism searching for food (mostly bacteria). Eventually, the moving colony of amoebas anchors itself. Some of the superorganism's cells specialize to create a stalk called a "fruiting body." The amoebas in the fruiting body change into spores and are wafted away on the wind. In this way, the simple, lowly amoebas are transformed into a radically different entity. One wonders how this superorganism, this slime mold, is controlled. Where are its sensors and its information processing center, if it possesses one? (Stewart, Ian; "Spiral Slime," Scientific American, 283:116, November 2000.) This question becomes more difficult to answer when we learn that slime molds can display rudimentary intelligence in the sense that they can solve mazes in their search for food. They are not as ...
Terms matched: 1 - Score: 69 - 15 May 2017 - URL: /sf133/sf133p08.htm
... Science Frontiers ONLINE No. 130: JUL-AUG 2000 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Has Human Evolution Been Directed by Bacteria?With considerable fanfare, a multinational team of scientists has announced that the mtDNA (mitochondrial DNA) "squeezed" from a 29,000-year-old Neanderthal skeleton found in the northern Caucasus differs by 3.48% from the mtDNA of a 40,000-year-old Neanderthal skeleton from (fittingly) Germany's Neander Valley. Furthermore, both mtDNA samples differ from that of modern humans by a substantial 7%. These two innocent-appearing, widely publicized numbers have far-reaching implications: Modern humans and Neanderthals are only very distantly related, and they certainly never interbred, as suggested in many recent, popular articles; and Since neither Neanderthal mtDNA sample is closer to that of modern Europeans than it is any other modern human population, the so-called "multiregional" theory of human evolution and dispersion is unlikely to be correct. Thus, the out-of-Africa theory is favored;. These data and their implications stimulate several observations and comments; only one of which is mentioned in the references given below. F.H . Smith, an anthropologist from Northern Illinois University and a supporter of the multiregional theory, opines that 30,000-40,000 years ago the mtDNA of the early humans, who were mixing it up with the Neanderthals, was certainly very different from what it is today. Since mtDNA mutates rapidly, ...
Terms matched: 1 - Score: 69 - 15 May 2017 - URL: /sf130/sf130p06.htm
... whole ocean systems . . Gel is like the dark matter of the sea. While sea gel does not impede the snorkeler, . it does herd microbes into clumps or microniches . which we cannot see either. These microbes. in effect, exist in a tangled. 3-D mesh that affects not only their movements but also those of their prey and predators. A few statistics confirm the amazing complexity of the seawater microcosm and its incredibly high microbe population density. The long strands in the oceanic gel are mostly crosslinked polysaccharides. If the polysaccharides in 1 milliliter of seawater could be placed end-to-end, they would stretch out to 5,600 kilometers! Coexisting proteins would span 310 kilometers ; DNA, 2 kilometers. This same milliliter may also contain up to a million bacteria and ten times as many virus particles. Also in this brew are, on the average, 1.000 protozoans and 100 phytoplankton. It's a microscopic metropolis, about the size of a sugar cube, and one in which you may never wish to swim again! The polysaccharides and proteins that comprise most of the thin goo are not alive, although the bacteria are. Just how this thin goo and its multitudinous inhabitants evolved has not been explained. Which came first, the goo or the bacteria? Being devoid of life's spark, the goo cannot evolve, or can it? (LaFee, Scott; "Meet Me at the Goo," New Scientist, p. 44, November 25, 2000.) Comment. Do similar microcosms thrive in freshwater ...
Terms matched: 1 - Score: 43 - 15 May 2017 - URL: /sf134/sf134p09.htm
... Issue Sourcebook Project Sourcebook Subjects "Uprooting the Tree of Life"Yes, that is the title of a long article in the February 2000 issue of Scientific American. In the Table of Contents, we see words concerning this article that we never thought would be permitted in a mainstream science magazine. After first noting that 10 years ago it was generally agreed that all organisms evolved from a single ancestral cell that existed about 3.5 billion years ago, there comes the assertion that the Tree of Life: "is far more complicated than was believed and may not have had a single root at all." The article proper relates how the Tree of Life has its own evolutionary history. Twenty years ago, scientists had that single ancestral cell splitting into two main trunks: the prokaryotes (bacteria) and the eukaryotes (every-thing else). More recently, a third trunk has been grafted onto the Tree; namely, the archaea (microorganisms that look like bacteria but possess markedly different genes). The archaea favor extreme environments and, curiously, are more closely related to you and me than are the bacteria. But according to this article (by W.F . Doolittle), the triple-trunked Tree of Life is simplistic. One reason for this is that genes, once thought to flow only from parent to progeny, are now known to travel laterally. Species barriers are broken. Genes jump from trunk to trunk, from branch to branch, twig to twig. Of course, these jumps are seen primarily among the microorganisms. The real Tree of ...
Terms matched: 1 - Score: 39 - 15 May 2017 - URL: /sf128/sf128p05.htm
... Science Frontiers ONLINE No. 129: MAY-JUN 2000 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The Extremophilic Terraforming of Mars If we are to colonize Mars, we must make it more earthlike; and that is what terraforming does. Right now, the Martian atmosphere, surface temperatures, level of ionizing radiation, and noxious soil are inimical to delicate, complex life forms, such as us. But these hostile Martian conditions are easily endured by some bacteria, such as Deinococcus radiodurans . This bacterium, one of the extremophiles, lives in our sewage systems and other unpleasant places. It can survive desiccation, freeze-drying, and high radiation levels. D. radiodurans can do more than survive on Mars. It can begin to detoxify the soil and prepare the way for other pioneer microorganisms. And even more: What D. radiodurans can provide is a microscopic (and therefore easily portable) factory -- a kind of terra-forming toolkit -- from which any number of products potentially can be derived. Whether it is engineered to reduce metals, produce drugs for ailing astronauts or simply manufacture the polymers necessary for the production of thread, D. radiodurans , one of the world's oldest bacteria, may provide a means of expanding the limits of human imagination beyond the written sci-fi page. (Slotnick, Rebecca Sloan; "Extremophilic Terraforming," American Scientist, 88: 124, 2000.) Comment. Perhaps D. radiodurans is the oldest bacterium on earth. Having arrived eons ago on ...
Terms matched: 1 - Score: 29 - 15 May 2017 - URL: /sf129/sf129p03.htm
... Science Frontiers ONLINE No. 130: JUL-AUG 2000 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Biogenic Magnetite in ALH84001 Many scientists were justifiably skeptical about those tiny, worm-like shapes seen in Martian meteorite ALH84001. Said to be fossilized bacteria, the objects seemed much too small to be viable. Some experts suggested they were just abiotic crystal-line growths. K.L . Thomas-Keprta, who led the NASA team studying ALH84001, snorted that her group was not so stupid that it would mistake crystals for fossils. ( SF#116 ) Thomas-Keprta et al have now come forward with more evidence that ALH-84001 does indeed contain biogenic material. Those worm-like forms have iron-rich rims containing fine-grained crystals of magnetite, some of which possess a unique morphology and which are essentially identical to the magnetite crystals secreted by magnetotactic bacteria on earth. Their conclusion: In ALH84001, the presence of these elongated prismatic magnetite crystals embedded within the carbonate glo- bules, which clearly formed on Mars, represents strong evidence for life on early Mars. (Thomas-Keprta, Kathie L., et al; "Biogenic Magnetite within Martian Meteorite ALH84001," Eos, 80:F69, 1999.) From Science Frontiers #130, JUL-AUG 2000 . 2000 William R. Corliss Other Sites of Interest SIS . Catastrophism, archaeoastronomy, ancient history, mythology and astronomy. Lobster . The journal of intelligence and political conspiracy (CIA, FBI, JFK, MI5, NSA, ...
Terms matched: 1 - Score: 28 - 15 May 2017 - URL: /sf130/sf130p03.htm
... Science Frontiers ONLINE No. 134: MAR-APR 2001 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Speaking of ALH 84001 Among the various magnetic grains comprising ALH 84001 are some nanometersized, hexagonal prisms that are "indistinguishable" from those excreted by terrestrial magnetotactic bacteria: Just when scientists in general were convinced that ALH 84001's "worms" had a mineralogical (i .e ., non-biological) origin, along comes this revelation. The ALH-84001 controversy is not over yet. (Kerr, Richard A.; "Tiny Magnets Point to Martian Life," Science, 290:2242, 2000.) Comment. In terrestrial magnetotactic bacteria, these magnetic crystals are strung together to make a sort of compass needle that helps orient the organism in muck and other lightless and lowly habitats.) From Science Frontiers #134, MAR-APR 2001 . 2001 William R. Corliss Other Sites of Interest SIS . Catastrophism, archaeoastronomy, ancient history, mythology and astronomy. Lobster . The journal of intelligence and political conspiracy (CIA, FBI, JFK, MI5, NSA, etc) Homeworking.com . Free resource for people thinking about working at home. ABC dating and personals . For people looking for relationships. Place your ad free. ...
Terms matched: 1 - Score: 27 - 15 May 2017 - URL: /sf134/sf134p03.htm
... Frontiers ONLINE No. 133: JAN-FEB 2001 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Strange Red Slime In Mine In the 1960s, an abandoned mine in Wisconsin flooded with groundwater. Scuba divers could not resist the challenge. As they explored the murky depths, they chanced upon deposits of spongy, red slime. When analyzed, the slime was found to contain the first naturally produced nanocrystals. Nano-crystals, like those described above under BIOLOGY, had previously been grown only in the lab. Also like the artificial nanocrystals, those in the red slime did not aggregate randomly; they "rotate into structural accord with the adjacent particles." Whence the slime's 2-3 nanometer clumps of iron oxyhydroxide? Iron-oxidizing bacteria excreted them! (Anonymous; "Strange Crystal Growth Found in Mine," Science News, 158:207, 2000.) Question. Was the red slime a biofilm? From Science Frontiers #133, JAN-FEB 2001 . 2001 William R. Corliss Other Sites of Interest SIS . Catastrophism, archaeoastronomy, ancient history, mythology and astronomy. Lobster . The journal of intelligence and political conspiracy (CIA, FBI, JFK, MI5, NSA, etc) Homeworking.com . Free resource for people thinking about working at home. ABC dating and personals . For people looking for relationships. Place your ad free. ...
Terms matched: 1 - Score: 15 - 15 May 2017 - URL: /sf133/sf133p09.htm
... Science Frontiers ONLINE No. 130: JUL-AUG 2000 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The Midi-Chlorians are with Us!Whoops! We meant to write "mitochondria" in that title. In the movie Star Wars, Episode 1: The Phantom Menace, Jedi master Qui-Gon Jinn explains the origin of the supernatural powers possessed by Jedi knights. It arises, he says, from microscopic lifeforms called chlorians" that dwell within all living cells and reveal the will of the Force. Mitochondria are popularly seen as mere powerhouses within cells, with little influence on the organisms they inhabit. They are, it is believed, just the distant progeny of bacteria that invaded complex cells hundreds of millions of years ago. With only 37 genes in their arsenal, human mitochondria would not seem to pose any threat to humanity. After all, we have about 100,000 genes per cell. Of course, mitochondria do evolve separately from us, and this is a bit disconcerting. Could they be more than mere symbionts? The midi-chlorians of the Jedi knights were "good guys", but our mitochondria sometimes seem to be working for an insidious alien Force. There is good evidence that they: Selected which of your mother's germ cells matured to produce you; Have decided your odds of living to be 100; and May influence your being afflicted with Parkinson's and Alzheimer's , as well as rarer disorders. The first item (or "force") is the most ...
Terms matched: 1 - Score: 14 - 15 May 2017 - URL: /sf130/sf130p07.htm
... believed to have been blasted off the Martian surface by five or six impacts of much larger meteorites. All save one of these Martian meteorites have formation ages of about 1.3 billion years. The only part of the Martian surface believed to be 1.3 billion years old is the TMOM (Tharsis Montes and Olympus Mons) region. The rest of Mars -- about 90% of it is much older. To have 12/13ths. of the Martian meteorites originate from 1/10th. of the planet's surface is highly unlikely. Something is wrong somewhere; probably a bad assumption. And what about that 13th. meteorite that did not get ejected from the TMOM region? This is ALH 84001, the controversial meteorite that contains strange worm-like structures resembling terrestrial bacteria. (See SF#130, #116, #110, #108, and #101.) (Taylor, Richard L.S ., and Mittlefehldt, David W.; "Missing Martian Meteorites," Science, 290:273, 2000.) From Science Frontiers #134, MAR-APR 2001 . 2001 William R. Corliss Other Sites of Interest SIS . Catastrophism, archaeoastronomy, ancient history, mythology and astronomy. Lobster . The journal of intelligence and political conspiracy (CIA, FBI, JFK, MI5, NSA, etc) Homeworking.com . Free resource for people thinking about working at home. ABC dating and personals . For people looking for relationships. Place your ad free. ...
Terms matched: 1 - Score: 14 - 15 May 2017 - URL: /sf134/sf134p02.htm
... large and complex that one is unsure that physics is up to the task of explaining these tangled structures consisting many hundreds of atoms. Some of these doubts have been relieved by recent advances in protein chemistry. It appears that the different types of protein folds, which number in the thousands, can be classified and sorted into distinct structural families -- just like the much simpler crystals of salt, quartz, galena, etc fall into orderly classes. The clear implication is that protein folds and, by extension via further research, the protein molecules themselves, are also natural and reducible just like the salt crystals. If proteins are natural, perhaps even more complex biological forms are also, and so on up the complexity ladder to viruses (which often look like crystals through the microscope), bacteria, and even (gasp!) mammals. This is, of course, reductionism in the extreme. But the successes with protein folding have led two New Zealand biochemists to speculate as follows: If it does turn out that a substantial amount of higher biological form is natural, then the implications will be radical and far-reaching. It will mean that physical laws must have had a far greater role in the evolution of biological form than is generally assumed. And it will mean a return to the pre-Darwinian conception that underlying all the diversity of life is a finite set of natural forms that will recur over and over again anywhere in the cosmos where there is carbon-based life. (Denton, Michael, and Marshall, Craig; "Laws of Form Revisited, ...
Terms matched: 1 - Score: 13 - 15 May 2017 - URL: /sf136/sf136p07.htm
... Neurons Do Advanced Math," Science, 292:185, 2001.) Hornets Install Magnetic Markers. Hornets of the species Vespa orientalis affix a tiny crystal of magnetic mineral in the roof of each of the brood-rearing cells in their nests. These crystals are roundish and about 0.1 millimeter in diameter. The mineral is ilmenite with the formula: FeTiO3. The purpose of the magnetic crystals is obscure. The favored explanation is that the hornets use them as guides during nest construction -- sort of like those little flags human surveyors set out. This explanation assumes that hornets can somehow sense and make use of the complex magnetic field created by an array of many tiny magnets. Another question asks where the magnetic crystals come from. Do the hornets secrete them like the magnetotactic bacteria or do they gather them from their environments? (Stokroos, Ietse, et al; "Keystone-Like Crystals in Cells of Hornet Combs," Nature, 411:654, 2001.) Comment. It would be so easy to dismiss the hornets' little crystals as just one more animal gee-whiz fact, but we should not. Did the hornets first recognize that magnetic crystals would be useful to them and then set out to find some or, even more remarkably, evolve the ability to secrete them? Did their (presumed) magnetic sense evolve solely for the purpose of employing magnetic markers during nest building? There are more questions, but you get the idea. From Science Frontiers #138, NOV-DEC 2001 . 2001 William R. Corliss Other Sites ...
Terms matched: 1 - Score: 13 - 15 May 2017 - URL: /sf138/sf138p04.htm
