270 results found.
... Science Frontiers ONLINE No. 87: May-Jun 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Cosmic Soot And Organic Asteroids Just as we were getting used to carbonaceous chondrites and tarry comets, we have been hit with cosmic soot and organic asteroids. Truly, it seems as if the universe is one vast factory of complex chemicals. This is not a trivial observation, for it betrays a synthesizing, efflorescent cosmos rather than a universe slowly succumbing to the deepfreezing Second Law of Thermodynamics. Any of these soots and tars wafting down upon the surface of a suitable planet might initiate or accelerate life processes. Cosmic soot. A 70-year-old astronomical enigma is the origin of the DIBs (Diffuse Interstellar absorption Bands). These dark absorption bands in stellar spectra have never been correlated with known chemical compounds. Now, L. Allamandola and F. Salama (NASA-Ames) find that the DIBs may be due to polycyclic aromatic hydrocarbons! A more digestible descriptor would be "soot," like that found in automobile exhaust and on your barbecued steak. (Weiss, Peter; "Cosmic Soot Fills Space between the Stars," New Scientist, p. 15, March 13, 1993.) Organic asteroids. Some asteroids are abnormally red. Newly discovered asteroid 5145 Pholus is 3 times brighter at near-infrared wavelengths than it is in the visible portion of the spectrum. The best explanation so far for this redness is that 5145 Pholus is veneered with organic compounds called "tholins." Tholins are synthesized ...
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... Science Frontiers ONLINE No. 82: Jul-Aug 1992 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The humongous organism contest!When we read of that 10,000-kilogram fungus discovered in Michigan, it sounded like a good item for Science Frontiers. But then it was described as the "largest and oldest living organism," and we knew that if we waited a couple months this Guinness-like record would be eclipsed. (Superlatives are risky in this business!) A killer fungus in Washington State. In the foothills of Mount Adams, a specimen of the fungus Armillaria ostoyae covers 1,500 acres and seems to be 400-1 ,000 years old, as comapred to the 38-acre, 1,500-year-old Michigan fungus. Although younger than its Michigan counterpart, the Washington fungus is lethal and can wipe out whole populations of trees. (Anonymous; "The Great Fungus," Nature, May 21, 1992.) Comment. It has also been reported that a huge, spreading, pathological growth exists in Washington, DC ! Some even more humongous plants. "A grass clone, Holcus mollis , has been found with a diameter of 900 metres and an age of over 1000 years. A clone of box-huckleberry has been found with a diameter of 2000 metres and an age of 13 000 years. The big granddaddy is, however, an aspen ( Populus fremaloides ) covering 81 hectares and over 10 000 years old." (Bullock, James; ...
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... Science Frontiers ONLINE No. 133: JAN-FEB 2001 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Superorganisms: From Simplicity To Complexity Superorganisms are biological entities made up of large numbers of simpler entities that have banded together to perform functions they cannot do as individuals. Termite mounds are often mentioned as superoganisms. But here we examine colonies of organisms that are much simpler and much smaller than termites. What entices the anomalist to attend to superorganisms? Here are two of the several questions superorganisms raise. How do superorganisms evolve properties that its constituent individuals do not possess, such as mobility, unique sensors, and even a modicum of intelligence. Since superorganisms do not reproduce as superorganisms, how can natural selection operate on these superorganisms? Salps. Books dealing with the unexplained sometimes include a photograph of a huge marine creature identified as a sea monster. This famous photo is real and so is the monster in it. But this creature is not reptilian; it is really a salp, a colonial tunicate. Tunicates are tiny, primitive marine organisms usually classified as invertebrates. Some species of tunicates have somehow acquired the habit of aggregating in immense numbers to create long, hollow, snake-like tubes called "salpa." Salps may reach lengths of 45 feet, with diameters of 3 feet. No wonder they are falsely identified as sea monsters. Structurally, the tunicates comprising the salp are embedded in a gelatinous wall facing inward. Each possesses a siphon that pumps nutrient-carrying sea water. Working in unison, the tunicates create ...
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... form of galaxies, is undergoing a colossal expansion. Gas, condensed into stars, is radiating thermonuclear energy out across an infall of matter, drawn by gravity. The simplest of chemical reactions and the most complex of biological activities are occurring on the surface of the earth in a state far from equilibrium; they are heated by the sun and cooled by the vacuum of space. This pervasive cosmic imbalance is the driving force in producing an environment conducive to the formation of structure and complexity." This sweeping statement seems to apply to the entire universe. The Second Law of Thermodynamics, however, insists that, on the average, for the entire universe, the above paragraph cannot be true. The article introduced by this unqualified assertion about the evolution of the universe is really about self-organizing chemical reactions. We classify it under biology because the authors imply that some biological phenomena are self-organizing. The famous Belousov-Zhabotinskii reaction is used as the prime example of chemical self-organization. First, one takes a shallow dish filled with a solution of bromate ions in a highly acidic medium. Here's what happens: "A dish, thinly spread with a lightly colored liquid, sits quietly for a moment after its preparation. The liquid is then suddenly swept by a spontaneous burst of colored centers of chemical activity. Each newly formed region creates expanding patterns of concentric, circular rings. These collide with neighboring waves but never penetrate. In some rare cases rotating one-, two-, or three-armed spirals may emerge. Each pattern grows, impinging ...
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... Science Frontiers ONLINE No. 58: Jul-Aug 1988 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Bacteria One dictionary's definition: "Widely distributed group of microscopic, one-celled vegetable organisms..." As a matter of fact, the nearly universal image of a bacterium is that of a simple, single-cell organism. But: "That view is now being challenged. Investigators are finding that in many ways an individual bacterium is more analogous to a component cell of a multicellular organism than it is to a free-living, autonomous organism. Bacteria form complex communities, hunt prey in groups and secrete chemical trails for the directed movement of thousands of individuals." J.A . Shapiro, author of the preceding quote, attributes the simplistic picture of bacteria to medical bacteriology, in which disease-causing bacteria are classically identified by isolating single cells, growing cultures from them, and then showing that they cause the disease in question. In the microscopic real world, bacteria virtually always live in colonies, which possess collective properties quite different and much more impressive than those of the single-cell-in-a -dish! That old human urge for reductionism has led us astray again. Shapiro seeks to remove the blinders of reductionism in a wonderful article in the June, 1988, issue of Scientific Amer can . We have room here to mention only the Myxobacteria, many of which never exist as single cells in nature. Even those that do are "social" in the sense that ...
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... A comet impact: Cross-sectional view 0.637s after impact of a comet into a 3km-deep ocean (light dots) underlain by basaltic crust (darker grid) in the smoothed particle hydrodynamic model of Thomas et al. Small vertical ticks are 1 km apart, small horizontal ticks 1.25 km apart. The comet in this figure has a radius of 1 kilometer and an impact velocity of 15 km/s and is shown by dark dots in the ocean. The initial spherical comet has become flattened, and parts of it have separated from the main body. The back side of the comet and most of the separated particles are much lower in temperature than the impacting side, and in an impact of a smaller comet (which would look much the same), organic material at the rear of the comet would survive intact. Figure provided by Paul Thomas. "New simulations suggest that large amounts of the organic molecules needed to form the first life on Earth could have been brought by comets that bombarded the planet early in its history. The models show that comets of moderate size would have slowed down enough during entry into the Earth's atmosphere for their organic component to survive the impact intact. .. .. . "The idea that comets supplied the Earth with the organic material needed to create life has been around for more than 20 years, but as often as some scientists have put forth the hypothesis, others have shot it down. "About 20% of comet nuclei are composed of organic matter, the rest ice and dust. ...
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... Science Frontiers ONLINE No. 35: Sep-Oct 1984 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The Immune System As A Sensory Organ John Maddox, the editor of Nature, has written a remarkable editorial on psychoimmunology; that is, the science of the brain's effects on the body's immune system. It is basically a running commentary on new discoveries that are helping us to understand this poorly appreciated relationship. Maddox begins by mentioning the 20-plus-year collection compiled by Professor G.W . Brown, University of London, of life-events that affect the health of outwardly normal people. Typical life-events are the death of a spouse, imprisonment, personal bankruptcy, etc. Everyone seems to recognize -- if only through anecdotes -- that mental states affect health, but how this brain-body link is maintained is hard to pin down. D. Maclean and S. Reichlin (Psychoneuroimmunology, 12: 475, 1981.) have reviewd some of the possible connections. One potential link is through the interaction of the hypothalamus on the pituitary. The pituitary is a source of materials that influence the immune system. Maddox lists several specific candidates, and then observes: "The more radical psychoimmunologists talk as if there is no state of mind which is not faithfully reflected by a state of the immune system." So far, not too radical! But then Maddox comes to an article by J.E . Blalock, University of Texas (Journal of Immunology, 132: ...
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... Science Frontiers ONLINE No. 37: Jan-Feb 1985 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The genome's responses to challenges The genome is an organism's genetic endowment. It contains instructions for the organism's growth and development, but it is not like a rigid, uncompromising computer program. Rather, the genome: ". .. is a highly sensitive organ of the cell that monitors genomic activities and corrects common errors, senses unusual and unexpected events, and responds to them, often by restructuring the genome. We know about the components of genomes that could be made available for such restructuring. We know nothing, however, about how the cell senses danger and instigates responses to it that often are truly remarkable." Thus Barbara McClintock ends the paper she delivered in Stockholm when she received a Nobel Prize in 1983. Most of McClintock's paper reviews her pioneering work with the corn genome, but she adds some examples of other genomic responses to external stresses. One such stress is applied to an oak tree when a wasp lays its egg in a leaf. The stress causes the oak genome to reprogram itself and construct a wholly new and unplanned plant structure to house and feed the developing insect. Some of these structures (galls) are very elaborate and are precisely tailored to each different wasp species. From such examples, it is apparent that the genome of an organism somehow perceives stresses and reacts to them -- often in completely unanticipated ways. The stresses may be mechanical, thermal ...
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... 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 Life-creation from a different perspective The preceding discussion of life's origin at hydrothermal vents was penned by an oceanographer. Astronomers, it seems, prefer different scenarios. C. Chyba and C. Sagan, in a major review article in Nature, see a two-fold problem: (1 ) identifying the source of the raw materials; and (2 ) identifying the source(s ) of energy required for the synthesis of complex organic chemicals. First, they point to the steady drizzle of tiny, organic-rich particles drifting down to earth from cometary debris. These particles, which even carry spacesynthesized amino acids down to the earth's surface, seem likely chemical precursors of life. However, the atmosphere is also a potential source of prebiotic chemicals -- providing energy sources are available. Chyba and Sagan suggest as sources: lightning, ultraviolet radiation, and the shock energy derived from meteorite/asteroid/comet impacts. Together these energy sources, especially ultraviolet light, might synthesize thousands of tons of complex organic compounds each year. (Chyba, Christopher, and Sagan, Carl; "Endogenous Production, Exogenous Delivery and Impact-Shock Synthesis of Organic Molecules: An Inventory for the Origins of Life," Nature, 355:125, 1992. Also: Henbest, Nigel; "Organic Molecules from Space Rained Down on Early Earth," New Scientist, 2. 27, January 25, ...
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... Science Frontiers ONLINE No. 75: May-Jun 1991 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Can organisms direct their evolution?" In 1988. Harvard molecular biologist John Cairns committed an act of scientific heresy. He proposed in a Nature article that bacteria living in an unfavorable environment are able to choose which mutations to produce to adapt to the stressful situation. Cairns made his directed-mutation hypothesis in response to an unusual finding -- data that strongly hinted bacterial mutations might occur more often when beneficial." The above quotation is the lead paragraph in a long BioScience article that details the consternation Cairns' results have created in the biological community. The problem that biology-as-a -discipline has is that it has deified a paradigm: neo-Darwinism. Now, neo-Darwinism is supported by many experiments showing that some mutations are indeed random. Consequently, as M. Gillis re-marks in her BioScience article, the biological community 'got locked into its belief that an organism cannot control its own mutation.' Furthermore, Cairns' claims recall the long battle with Lamarckism, a subject that biology has closed-the-book-on. In a nutshell, Lamarckism has been interred since the 1950s, and 'Nobody wants to give the appearance of straying from the neoDarwinism fold.' Gillis goes on to review some recent experiments supporting those of Cairns. But, impressive though these may be, there have been neo-Darwinian explanations for some of the results. Even so, more and ...
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... Science Frontiers ONLINE No. 65: Sep-Oct 1989 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Fossil from mars?Who would have thought that the dreary Antarctic wastes would harbor a piece of Mars, much less a fossil of Martian life? Yet, British scientists, I.P . Wright et al, in Nature, come close to such a conclusion. "The meteorite EETA 79001, which many believe to have originated on Mars, contains carbonate minerals thought to be Martian weathering or alteration products. Accompanying the carbonates are unexpectedly high concentrations of organic materials (defined here as carbonaceous matter that has a low stability towards oxidation, and so combusts at less than 600 C; the term 'organic' does not necessarily imply an origin by biogenic processes.) Although the carbon isotope composition of these materials is indistinguishable from terrestrial biogenic components, and so cannot be used to assess the source, we argue here that their occurrence in an interior sample of a clean Antarctic meteority militates against a wholly terrestrial origin. A sample of Martian organic materials may thus be available for further study in the laboratory." (Wright, I.P ., et al; "Organic Materials in a Martian Meteorite," Nature, 340: 220, 1989.) But there are many "buts": Meteorite EETA 79001 may not have come from Mars after all, even though many scientists think it did. The organic material in EETA 79001 may have come instead from the comet that supposedly blasted the meteorite into space from the ...
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... Other Geophysical Activity EQ SEISMIC PROBING OF INNER EARTH EQA LOCALIZED STRUCTURES IN THE CORE AND MANTLE EQA1 Stratification of Basement Rocks EQA2 Deep Continental Roots EQA3 Deep Penetration of Subducted Slabs EQA4 Lateral Inhomogeneities in the Lower Mantle EQA5 Mysterious Structures at the Core-Mantle Boundary EQA6 Seismic Reflectors EQD SEISMIC DETECTION OF LARGE SCALE DISCONTINUITIES, ZONES, STRUCTURES EQD1 Velocity Discontinuities EQD2 Channels and Zones EQD3 Structural Anomalies of the Inner Core EQD4 Anomalies Associated with Mantle Convection Cells EQQ ANOMALOUS SEISMIC SIGNALS EQQ1 Deep-Focus Earthquakes ES STRATIGRAPHIC ANOMALIES ESA EMBEDDED ACCRETION STRUCTURES ESA1 Cylindrical Structures in Rock and Unconsolidated Sediments ESA2 Spherical Aggregates ESA3 Concretions ESA4 Small Fused Structures ESA5 Geodes ESA6 Orbicules ESB ANOMALOUS BIOLOGICAL PHENOMENA IN GEOLOGY ESB1 Biological Extinction Events ESB2 Biological Explosion Events ESB3 Recent Vegetation and Shallow Water Fossils at Great Depths ESB4 Long-Buried, Undecomposed Organic Matter ESB5 Living and Fossil Marine Organisms Found Far Inland ESB6 Living Organisms and Recent Fossils at Very High Altitudes ESB7 Growth Structures on Marine Organisms and Their Fossils ESB8 Animals Entombed in Rocks ESB9 Living Organisms at Great Depths ESB10 Fossils of Warm-Climate, Light Dependent Organisms Found in the Polar Regions ESB11 Time-Wise Anomalous Fossils ESB12 Skipping in the Fossil Record ESB13 "Special" Nature of Fossils ESC ANOMALOUS CHEMICAL PHENOMENA IN GEOLOGY ESC1 Chemical Anomalies in the Stratigraphic Record ESC2 Chemical Anomalies in Igneous and Metamorphic Rocks ESC3 Surface Films on Rocks ESC4 Spontaneous, Rapid, Exothermic Reactions in Nature ESC5 Death Gulches ESC6 Violent Lake Turnovers ESC7 Petrifactions and Lignifications ESC8 Geological Effects of Natural Combustion ESC9 Rocks and Sediments of Controverted Origins ESC10 Unusual Growth Structures ESC11 Possible Extraterrestrial Origin of Ocean Water ESC12 Chemical Anomalies of Lakes ...
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... meant. The "first" dust may not have been terrestrial dust but interplanetary dust. Let us commence with long-winged U2s cruising at 20 kilometers altitude or more. Collectors coated with silicone oil are deployed. To them stick tiny bits of interplanetary and interstellar debris that have been caught by earth's gravity and are slowly drifting downward in the atmospshere. Some of these micron-sized particles come from asteroid collisions; others from the disintegration of comets. This rain of cosmic matter is not negligible; the earth harvests about 40,000 tons annually from the fertile fields of outer space. "Fertile?" Yes, outer space is a vast biochemical retort. D. Brownlee, R. Walker, and others: ". .. suggest that interplanetary dust has probably carried organic matter to Earth since the early aeons of the solar system. The complexity of the organic molecules found on these particles has fueled the imaginations of many who ponder the role extraterrestrial matter may have played in the prebiological evolution of organic material on the primordial Earth." Beyond these conjectures, several other things about interplanetary dust particles bother scientists: "' What is surprising,' Walker notes, 'and still not understood, is the fact that the organic molecules we see in the dust particles are different from those previously seen in meteorites.' Another enigma is the observation of striking isotopic anomalies -- large enrichments of deuterium relative to hydrogen, as much as ten times greater than one sees in terrestrial samples -- in the particles in which Zare's group observed the organic molecules ...
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... Science Frontiers ONLINE No. 52: Jul-Aug 1987 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Meteorites Also Transport Organic Payloads Excerpts from the Abstract of a paper printed in Nature: "Much effort has been directed to analyses of organic compounds in carbonaceous chondrites because of their implications for orgainc chemical evolution and the origin of life. We have determined the isotopic composition of hydrogen, nitrogen and carbon in amino acid and monocarboxylic extracts from the Murchison meteorite. .. .. . "These results confirm the extraterrestrial origin of both classes of compounds, and provide the first evidence suggesting a direct relationship between the massive organo-synthesis occurring in interstellar clouds and the presence of pre-biotic compounds in primitive planetary bodies." (Epstein, S., et al; "Unusual Stable Isotope Ratios in Amino Acid and Carboxylic Acid Extracts from the Murchison Meteorite," Nature, 326:477, 1987.) From Science Frontiers #52, JUL-AUG 1987 . 1987-2000 William R. Corliss ...
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... is transmitted through the material they are resting on. You and I cannot hear caterpillar songs, but some ants can, and they are attracted to these insect sirens. The singing caterpillars belong to the Lycaenidae, which include such butterflies as the hairstreaks and blues. It is not only the singing or vibrating of this group of caterpillars that makes them remarkable, it is the complexity of their symbiotic relationships with several species of ants and a plant. Since both the ants and the caterpillars favor the Croton plant, they could well meet by chance, but the caterpillars' singing serves to accelerate contact. Once met on the Croton plant, a fascinating triangle is completed. Player 1. The Croton plant provides nourishment to the caterpillars through both its leaves and specially evolved nectaries (nectar-producing organs), but receives nothing in return. The ants also dote on the nectaries, but they at least protect the plant from all herbivorous insects except the singing caterpillars. Player 2. The ants get food from both the Croton plant and the caterpillars. The latter have evolved extrudable glands called "nectary organs." For their part of the bargain, the ants protect the caterpillar from predatory wasps, just as they defend the Croton plant from its enemies. Player 3. The caterpillars, though seemingly benign, are the heavies in this menage-a -trois! They get both leaves and nectar from the plant for nothing. They do supply the ants with nectar in exchange for protection, but subtle subversion prevails here! First they attract the ants with their songs; then, ...
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... Science Frontiers ONLINE No. 115: Jan-Feb 1998 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Why did life take a left turn?Life-as-we-know-it is left-handed; that is, our amino acid molecules are levorotatory rather than the mirror-image dextrorotatory versions. Because humans "expect" symmetry in nature, it is taken for granted that everything else in the universe is split equally between leftand right-handed molecules. Earth life is just a fluke -- or is it? On September 28, 1969, organic-rich stones fell in Victoria, Australia. This was the Murchison meteorite, and it may carry a message. Over a decade ago, M.H . Engel and B. Nagy reported that the organic molecules in the Murchison meteorite were not split 50:50 between left- and right-handed versions. So contrary to expectations was this finding that most scientists assumed that the analysis was contaminated by terrestrial organic molecules. Now, M.H . Engel and S.A . Macko have refined the analytical techniques and apparently avoided any taint of contamination. Their conclusion: the Murchison amino acids still lean to the left. From all this arise several intriguing possibilities: Life on earth started split evenly between left- and right-handed amino acids, but was nudged to the left by the influx of organic-laden meteorites like the Murchison. Terrestrial life actually originated elsewhere in the universe where much matter is left-handed, including life, if ...
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... 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 Self-organized stone stripes "Geometrically regular stripes of stones are found on many unvegetated alpine and polar hillslopes; known as 'sorted stripes' because of the characteristic textural sorting between surface stones and fine-grained soil, they contrast markedly with the lack of order typical of natural landscapes. The spacing of the stripes can range from centimeters to meters (about 10-20 times the average stone diameter), with individual stripes extending downslope for many tens of meters. A variety of formative mechanisms have been proposed, but it is still unclear how such orderly stripes can arise spontaneously, and what dictates the spacing." B.T . Werner and B. Hallet, authors of the foregoing partial abstract, have mathematically simulated the displacement of surface stones under the forces generated by the growth of needle ice in the underlying soil. As the number of freeze-thaw cycles increases into the thousands, computer simulations show the surface stones gradually arraying themselves into linear patterns. (Werner, B.T ., and Hallet, B.; "Numerical Simulation of Self-Organized Stone Stripes," Nature, 361:142, 1993.) Reference. These stone stripes represent just one type of "patterned ground." Other examples may be found in ETP1 in our catalog: Carolina Bays, Mima Mounds, described here . From Science Frontiers #88, JUL-AUG 1993 . 1993-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 115: Jan-Feb 1998 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects A SUBMARINE ORGAN?Exactly two years ago, we reported on strange seismic signals detected by German geophysicists near Mount Semeru, in Java. These signals consisted of a fundamental tone and evenly spaced harmonics. Sometimes, the fundamental tone rose and fell. This "natural trombone" was thought to be a gas-filled subterranean cavity capped at the top by rock, with a pool of magma at the bottom. Volcanic vibrations resonated in this chamber. As the magma pool rose and fell, the fundamental tone changed. More recently, a network of seismic stations in French Polynesia has picked up more mysterious seismic signals. These differ from those in Java in that each fundamental tone is "pure"; that is, there are no harmonics. Dubbed "T -waves," the sounds originated from an active volcanic ridge in the South Pacific. Suspicion fell on one flat-topped volcano that rose to within 130 meters of the ocean surface. But, how could this peak generate such a pure tone? The theory is that the active volcano spews out a column of steam bubbles bounded at the bottom by the flat volcano and by the ocean at the top. Computer simulations proved that sound could resonate in a column of bubbles just as it does in an organ pipe. Since the height of the column remains fixed, so does the fundamental tone. Certainly harmonics are generated, too, but the bubbles damp out the ...
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... Late Survival of Moas and Passenger Pigeons BBD5 Distribution Curiosities BBE THE FOSSIL RECORD OF BIRDS BBE1 The Fossil Record of Birds and Associated Paradigms BBE2 Evidence against the Dinosaur Origin of Birds BBE3 Protoavis: A Pre-Archaeopteryx Bird? BBE4 Unresolved Nature of Archaeopteryx BBE5 The Apparent Absence of Transitional Forms of Feathers BBE6 Fossils of Ostrich Ancestors in the Northern Hemisphere BBE7 Controversial Feathers of the London Archaeopteryx Fossil BBE8 Giant Fossil Eggs BBF BODILY FUNCTIONS BBF1 The Avian Respiratory System: Unique, Complex, Sophisticated BBF2 Avian Bodily Functions: Some Oddities BBG GENETICS BBG1 Species mtDNA More Diverse Than Morphology BBG2 Discordance in the Date of Divergence of Modern Birds BBG3 Discordances between Phylogenies Established from Morphology and DNA Analysis BBG4 Dearth of Introns in Birds BBI INTERNAL STRUCTURES AND SYSTEMS BBI1 Avian Magnetoreceptors: Hard to Find BBI2 Curious Internal Structures BBO ORGANS BBO1 Complexity and Sophistication of Some Owl Ear-Brain, Sound-Localization Systems BBO2 Regeneration of Brain Neurons BBO3 Curiosities of Avian Brains BBO4 The Pecten: A Unique Structure in the Avian Eye BBO5 Curiosities of Avian Eyes BBO6 High Complexity and Sophistication of the Avian Eye BBO7 Remarkable Tongue Adaptations BBO8 The Loss and Reduction of Reproductive Organs BBT UNUSUAL TALENTS AND FACULTIES BBT1 Infrasound and Atmospheric Pressure-Change Detection BBT2 Utility of Ultraviolet Vision in Birds BBT3 Echolocation: Parallel Evolution in Birds BBT4 Navigational Feats during Migration BBT5 Homing: Release Experiments BBT6 Curious Migration Phenomena: Navigation Errors? BBT7 Complexity and Sophistication of Avian Navigation BBT8 Inheritance of Migration Data BBT9 The Existence of Avian Migration BBT10 Sensitivity to Impending Weather and Earthquakes BBT11 Possible Unrecognized Senses BBT12 Remarkable Feats of Flight BBT13 The Origin of Avian Flight BBT14 Unanswered ...
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... Science Frontiers ONLINE No. 107: Sep-Oct 1996 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Organ Music Your doctor is understandably concerned if he finds your heartbeat is irregular. But it turns out that the healthy heart does not beat steadily and precisely like a metronome. In fact, the intervals between normal heartbeats vary in a curious fashion: in a simple, direct way, they can be converted to musical notes. When these notes (derived from heartbeat intervals) are heard, the sound is pleasant and intriguing to the ear -- almost music -- and certainly far from being random noise. In fact, a new CD entitled: Heartsongs: Musical Mappings of the Heartbeat , by Z. Davis, records the "music" derived from the digital tape recordings of the heartbeats of 15 people. Recording venue: Harvard Medical School's Beth Israel Hospital! This whole business raises some "interesting" speculations for R.M . May. "We could equally have ended up with boring sameness, or even dissonant jangle. The authors speculate that musical composition may involve, to some degree, 'the recreation by the mind of the body's own naturally complex rhythms and frequencies. Perhaps what the ear and the brain perceive as pleasing or interesting are variations in pitch that resonate with or replicate the body's own complex (fractal) variability and scaling.'" (May, Robert M.; "Now That's What You Call Chamber Music," Nature, 381:659 ...
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... , when the research submersible Alvin was exploring those remarkable hydrothermal vents or "black smokers." Its CCD (Charge-Coupled Device) camera detected a ghostly glow emanating from the vents. Since this mineral-laden water gushing from these cracks in the deep-sea floor exits at 350 -400 C, the simplest explanation of the vent glow is that is is simply thermal radiation from the hot fluid. Indeed, color filters on the camera recorded a spectrum close to that of a 350 C plume. But the deep-sea shrimp camped around the vents have raised second thoughts. The shrimp, only a few inches long, live in the perpetual darkness of the miles-deep vents. They do not need and do not have ordinary eyes. Rather, they sport a mysterious organ on their backs that is connected to their brains by a nerve-fiber bundle much like an optic nerve. This organ is packed with the same light-sensitive pigments found in the eyes of surface creatures. Despite its unusual location on the shrimp, it is an "eye" of sorts. But of what use is it in the Stygian abysses? To find, perhaps, vent glows that betray the presence of chemosynthetic food sources. If this is so, the shrimps' optical organ, which is most sensitive in the blue-green portion of the spectrum, is badly mismatched to the infrared of the vent glow. It is a truism that nature is a perfectionist and would not tolerate such bad design. The eyes of animals are always well-tuned to their ways ...
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... This Issue Sourcebook Project Sourcebook Subjects Dragon fish see red Most fish that make a living in deep, dark ocean waters have eyes that are most sensitive to the blue part of the sun's rays (470-490 nanometers). These are the rays that penetrate to the greatest depths in the sea. This adaptation to blue light means that deepsea fish have evolved visual pigments different from those of surface fish and land animals. Visual pigments are complex chemical compounds, and one must suppose that many, many random mutations took place before deepsea fish were able to manufacture visual pigments different from their relatives living near the surface. (Or did deepsea fish come first?) But there is more to this story. Many dwellers in the black abysses generate their own light. They sport bioluminescent organs so they can be seen by others of their own species and, in addition, illuminate prey for easier capture. In another remarkable example of evolutionary convergence, these bioluminescent organs emit light spectrally matching the eye sensitivity of deepsea fish! So far, though, this story is not any more amazing that many others woven into evolution's fabric. But suppose that a deviant species of deepsea fish upset this cosy status quo by evolving visual pigment and bioluminescent organs operating in a part of the electromagnetic spectrum that other deepsea fish could not perceive. It would be as if this species had radar but the others did not! Well, three genera of dragon fish do have organs (photophores) that emit far-red light, and their eyes are correspondingly red-shifted by new visual ...
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... Science Frontiers ONLINE No. 46: Jul-Aug 1986 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Halley's comet infected by bacteria?" Halley's comet is coated with organic molecules. Two astronomers working with the Anglo-Australian Telescope, David Allen and Dayal Wickramasinghe, have found strong evidence in an infrared spectrum of the comet, taken two weeks ago. The spectrum, spanning the wavelengths 2-4 micrometres, shows a prominent feature centred at 3.4 micrometres which the two astronomers attribute to emission by carbon-hydrogen bonds in a solid." Chandra Wickramasinghe (Dayal's brother) states that the emissivity of Halley's comet matches exactly the emissivity of bacteria as observed in the laboratory. This observation supports the Hoyle-Wickramasinghe suggestion that comets transport life forms around the universe. Of course, more conservative scientists contend that rather complex organic molecules can be synthesized in space abiogenically. These molecules might account for the observations. (Chown, Marcus; "Organics or Organisms in Halley's Nucleus," New Scientist, p. 23, April 17, 1986.) Comment. This article seems to be accompanied by a bit of scientific revisionism. In response to this discovery, one English scientist remarked that these results, ". .. only confirm what everyone has always suspected." Now, it is true that comets have long been termed "dirty snowballs" but until very recently no one has maintained that comets are covered with dark, organic sludge. Reference. In category ...
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... 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 Archaea: the living ancestors of all life forms Life's place of origin may soon shift from that long-favored "warm little pond" to undersea hydrothermal vents. "Important new discoveries on the properties of the early earth and atmosphere, including the frequency and size of bolide impacts, have strongly implicated submarine hydrothermal vent systems as the likely habitat for the earliest organisms and ecosystems, while stimulating considerable discussion, hypotheses and experiments related to chemical and biochemical evolution. Some of the key questions regarding the origins of life at submarine hydrothermal vent environments are focussed on the effects of temperature on synthesis and stability of organic compounds and the characteristics of the earliest organisms on earth. There is strong molecular and physiological evidence from present-day mircoorganisms that the earliest organisms on earth were capable of growing at high temperatures (about 90 C) and under conditions found in volcanic environments. These 'Archaea', the living ancestors of all life forms, display a variety of strategies for growth and survival at high temperatures, including thermostable enzymes active at temperatures about 140 C. Further molecular and biochemical characterization of the presently cultured thermophiles, as well as future work with the many species, particularly from subsurface crustal environments, not yet isolated in culture, may help resolve some of the important questions regarding the nature of the first organisms that evolved on earth." (Baross, J.A .; "Hyperthermophilic Archaea: Implications for the ...
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... Science Frontiers ONLINE No. 11: Summer 1980 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Hierarchies Of Evolution All organisms from man to mouse to amoeba are merely DNA's way of manufacturing still more DNA -- so goes the modern ramification of molecular biology and the Genetic Code. In other words, DNA and genes are selfish, and ultimate parasites, directing the evolution of life only to maximize the production of DNA. This theme is not the subject of this paper by Doolittle and Sapienza. Rather, they wonder about those nonsense DNA sequences that do not code for protein. The presence of these "useless" bits of genetic material is often explained in terms of gene "expression." Emphasis is always on maximizing the "fitness" of the organism (phenotype). Perhaps this seemingly excess genetic material actually maximizes the fitness (survivability) of the DNA itself. Evolution thus occurs at DNA and gene (genome) levels, despite what transpires at the organism (phenotype) level. (Doolittle, W. Ford, and Sapienza, Carmen; "Selfish Genes, the Phenotype Paradigm and Genome Evolution," Nature, 284:601, 1980.) Comment. We know that mitochondria and chloroplasts have their own genetic material; evolution may be occurring at this level, too, independent of pressures for change on the organisms. Waxing speculative, may there not be other hierarchies where systems are trying to maximize their own survivability, even at molecular, atomic, and subatomic levels? Don't laugh! ...
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... Science Frontiers ONLINE No. 64: Jul-Aug 1989 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Directed Mutation Dear reader, things have a way of working out serially. For several months, we have had in our possession a paper from Nature, by J. Cairns, of Harvard, plus some passionate correspondence stimulated by the paper. Now that the circle-forming sheep have provided a good introduction, we will jump into the fray, too. Basically Cairns (in Nature) and B. H. Hall (in Genetics ) say that organisms can respond to environmental stresses by reorganizing their genes in a purposeful way. Such "directed mutation" shifts the course of evolution in a nonrandom way. Such a conclusion was like waving a red flag in front of the evolutionists. R. May, at the University of Oxford, complained, "The work is so flawed, I am reluctant to comment." On the other side, a University of Maryland geneticust, S. Benson, comments, "Many people have had such observations, but they have problems getting them published." Our template in this discussion is an article by A.S . Moffat in American Scientist. She says, "The stakes in this dispute are high, indeed. If directed mutations are real, the explanations of evolutionary biology that depend on random events must be thrown out. This would have broad implications. For example, directed mutation would shatter the belief that organisms are related to some ancestor if they share traits. ...
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... Science Frontiers ONLINE No. 30: Nov-Dec 1983 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Cancer: the price for higher life?For unknown reasons, plants and the simpler animals, such as sponges and jellyfish, do not get cancer. But all laterally symmetric organisms are prone to cancer. According to James Graham, the acquisition of cancer-initiating onco-genes by organisms (also an unexplained event) has forced these afflicted organ-isms to develop all sorts of defenses against external forces which might, with the help of the oncogenes, trigger cancer. Typical biological defenses include systems to insure accurate replication of cells, to destroy transformed cells, and to protect or immunize the organism against invading systems. Efficient im-mune systems in turn permitted life to invade mutagenic environments (such as sunlight) and to shed restrictive body coverings. In other words, cancer may have been a blessing in disguise -- the price of higher life| (Anonymous; "Cancer: The Price for Higher Life?" New Scientist, 99:766, 1983.) Comment. Note how easy it is for us to say "developed" this or that characteristic in response to some applied force. Exactly how such responses are made is a major mystery. And why do oncogenes exist? Are they a product of chance? They hardly confer short-term survival capability. Reference. The existence and insidious-ness of cancer pose many questions. These are broached in BHH23-35 in our catalog: Biological Anomalies ...
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... Science Frontiers ONLINE No. 17: Fall 1981 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects What was, is, and shall be Rupert Sheldrake, an English plant physiologist, has written a new book entitled A New Science of Life; The Hypothesis of Formative Causation. In it, he revives and expands the theory of morphogenic fields. Basically, this theory states that existing organized structures, such as crystals and organisms, establish fields that shape the future organization of matter into similar crystals and organisms in a probabalistic way. In other words, once a specific crystal (or life form) is synthesized, it sets up a morphogenic field that will make it easier to synthesize further the same, or nearly the same, crystal (or life form). To support his ideas, Sheldrake claims that it is common knowledge that a brand-new crystal form is difficult to synthesize at first but that further syntheses become easier and easier. The prevailing "scientific" explanation of this amazing fact is that fragments (seeds) of the initial synthesis are carried from lab to lab by humans and even the air! Morphogenic fields, however, explain such phenomena very nicely without postulating tiny crystal seeds in scientists' beards. Sheldrake then goes on to review McDougall's experiments in the 1920s in which trained rats from water mazes apparently passed their new knowledge on to their progeny. McDougall thought that he had proved the inheritance of acquired characteristics. Other biologists repeating his heretical experiments found that their first-generation rats solved the same water ...
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... Science Frontiers ONLINE No. 94: Jul-Aug 1994 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Cancer: a precambrian legacy?Throughout much of Precambrian time until the onset of the Cambrian period some 540 million years ago, single-cell organisms dominated the planet. The goal of each individual cell was to prosper and proliferate. Competition with other cells, including those of the same species, was intense. Altruism did not exist. The most successful species were those that were tough and aggressive. Nevertheless, as the Cambrian began, some single cells suppressed their mutual antagonisms and formed partnerships. Thus were born the first metazoans -- the multicellular species. The road was now open to the evolution of what we term "higher" life forms. But before really complex organisms could evolve, the selfish, aggressive characteristics inherited from the ancestral single-cell species had to be tamed. Unfortunately, some of the controls that evolved -- and which we have inherited -- do not always work. Conversely, they sometimes work too well. J.M . Saul has described how the appearance of cancer in complex multicellular organisms may be the consequence of the failure of biochemical controls evolved to curb cell aggression: "Such failure may be seen as reversion to ancestral cellular behavior, or as failure of a cell with a monocellular heritage to perform metazoan tasks for which it was not originally designed. In such instances, the resultant types of wild and indiscriminate proliferation and variation would resemble pathologies classified as 'cancer.'" ...
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... Chromosome Choreography Every biology student has seen sketches of the "dance of the chromosomes" that is performed when eukaryote (nucleuscontaining) cells divide. Because chromosomes are composed of genes and their DNA -- the information carriers of inheritance -- it reasonable to suppose that they are the "dance-masters." This expectation is enhanced if one holds that the genes are "selfish;" that is, they have their own evolutionary agendas, and all life forms exist only to execute their "will." But cell division would not occur at all without the action of the cell's bipolar spindle. This spindle is composed of microtubules -- rods of the protein "tubulin." Somehow , when cells are about to divide, they synthesize these microtubules, which then seem to organize themselves into orderly arrays (the bipolar spindles). Then, the microtubules sort out and separate the two sets of chromosomes required for the two new cells. So, far, our description conforms to what biologists have known and accepted for decades; but there is something more mysterious going on. In 1996, researchers discovered that they can actually substitute DNAcovered beads for the chromosomes, and the microtubules will still go through the motions of sorting and separating the chromosome-less strands. Actually, the microtubules will perform their act even without the DNA-covered beads. In a sense, the bipolar spindle is a puppetmaster, and the microtubules are the strings. The puppet show can go on without the puppets (chromosomes). (Hyams, Jeremy; "Look Ma, No Chromosomes ...
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... Science Frontiers ONLINE No. 103: Jan-Feb 1996 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects A Subterranean Trombone In 1992, while making seismic recordings near Java's Mount Semeru, a German scientific team noticed that the seismic waves were much more regular than one would expect from deep volcanic activity. Their recordings revealed a series of evenly spaced harmonic frequencies. They likened it to a musical instrument emitting a fundamental note accompanied by overtones. Sometimes, the fundamental tone would rise and fall, as if the mountain were playing a tune for them. The Germans, V. Schlindwein et al, postulated that the vibrations originated in a gas-filled cavity, presumably cylindrical -- something like an organ pipe -- capped at the top, with a pool of molten magma at the bottom. Volcanic vibrations resonated in this chamber and, as the magma pool rose and fell, so did the fundamental tone. Rather than a fixed organ pipe, it was a natural trombone! Unfortunately, the "earth music" was always in the infrasound range, 8 Hertz and less, and could not be heard by the researchers directly -- only their instruments could "listen." (Schneider, David; "Country Music," Scientific American, 273:28, November 1995.) Comments. There is no physical reason why such a subterranean trombone cannot play in the audible range. Such a mechanism might explain some of the mysterious hums heard in various localities, such as the Taos hum. (SF#88 ...
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... Science Frontiers ONLINE No. 108: Nov-Dec 1996 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Life Forms In Meteorites?Few could have escaped the recent gushy press coverage of NASA's announcement that an Antarctic meteorite, possibly of Martian origin, seems to have carried vestiges of life forms from that planet to ours. No need to recapitulate all that hype. What we do add is the observation that this same sort of excitement has swept through the scientific community at least twice before. Back in 1961, B. Nagy et al discovered tiny particles resembling fossil algae in carbonaceous chondrites. They called these particles "organized elements." Ultimately, these curious particles were explained as natural crystals and terrestrial contaminants. (Ref 1.) Much earlier, in 1881, Hahn, an eminent German geologist, asserted that he had examined thin sections cut from chondrites and found fossils of sponges, corals, and crinoids. In fact, the extraterrestrial coral that Hahn found even received the scientific name Hahnia meteoritica ! In the end, though, Hahn's meteoric life forms met the same fate as the "organized elements" of Nagy et al. (Ref. 2) Ref. 1. Urey, Harold C.; "Biological Materials in Meteorites: A Review," Science, 151:157, 1966. Ref. 2. Bingham, Francis; "The Discovery of Organic Remains in Meteoritic Stones," Popular Science Monthly , 20:83, 1881. Both references can be found in our Handbook Mysterious ...
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... Science Frontiers ONLINE No. 47: Sep-Oct 1986 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Heretical Evolutionary Theory "Over the past 15 years, away from the limelight of mainstream evolutionary argument, cell biologists have been debating a concept that is fundamental to our understanding of how cells evolved. It is the proposal that some of the structures that are found in the larger cells of animals, plants and fungi (eukaryotic cells) are the descendants of simpler bacteria-like organisms (prokaryotic cells) that had at some stage entered into an intracellular existence, or endosymbiosis. The idea is not a new one, but only in the light of modern experimental evidence has it become acceptable to many biologists. If the hypothesis is correct, then virtually all the major groups of familiar organisms originated 'suddenly' through endosymbiotic associations." Following this lead paragraph, with its paradigm-shaking final sentence, are three pages summarizing the biological evidence favoring evolution by endosymbiosis. (Kite, Geoffrey; "Evolution by Symbiosis; The Inside Story," New Scientist, p. 50, July 3, 1986.) Comment. We cannot possibly do justice to this exciting idea of evolution forced by the uniting of different organisms in the limited format of Science Frontiers. Instead, we encourage readers to purchase a new book by L. Margulis and D. Sagan (son of Carl Sagan and L. Margulis) entitled Micro Cosmos. In passing, we must also remark on the obvious relationship of endosymbiosis to F. Hoyle's ...
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... Science Frontiers ONLINE No. 76: Jul-Aug 1991 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Baby Oil Geologists maintain that most of the oil they pump out of the ground was formed tens and hundreds of millions of years ago from biological debris. But in the Guaymas Basin, in the Gulf of California, the oil seeping out of the sediments is only 4240 years old! Actually, it could be even 500-3000 years younger than that for two reasons: (1 ) The organic debris that was C-14-dated may have taken many years to become incorporated in the sediments; and (2 ) The dating may be skewed by older material in the sediments. By subtraction, the oil might be as young as 1240 years! The picture geologists draw of the Guaymas Basin is that of a spreading center covered by perhaps a half kilometer of sediments. Spewing up from the spreading center is hot water at 300-350 C, which "cracks" the organic material in the sediments, converting it into petroleum only 10-30 meters below the sea floor. (Hecht, Jeff; "Youngest Oil Deposit Found below Gulf of California," New Scientist, p. 19, April 6, 1991.) Comment. Since spreading centers are really cracks in the earth's crust, it is possible that some of the feed materials for this modern "petroleum factory" in the Guaymas Basin could consist of abiogenic, primordial methane and other organics seeping up from deep within the earth. Reference ...
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... Science Frontiers ONLINE No. 36: Nov-Dec 1984 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Is a dog more like a lizard or a chicken?Cladism has been around since at least 1950, when the German entomologist William Hennig began classifying organisms in a new way. "His method was simple: classifications of animals and plants should be based on an assessment of their characters, and only advanced, or derived, characters (synapomorphies) should be used. For example, the character 'possession of feathers' is a synapomorphy shared by all birds that is found in no other organisms; it is used in classification to define Class Aves. All birds have a backbone too, but that is a primitive character for birds because it is seen in all other vertebrates. Primitive characters are of no use in defining a monophyletic group." Early on, cladism ignited many fireworks in the biological community. Today, cladism has become quite respectable. The cladists, however, are now fighting among themselves. One camp draws their "cladograms" (see illustration) using evolutionary theory as a guide. The other side believes that the cladograms should be drawn up first, based only upon actual characters and ignoring the theory of evolution -- let the species fall where they may. When evolutonary theory is omitted in the deliberations, radically different cladograms result. Mammals then seem more closely related to birds than reptiles, for example, as expressed in the illustration. A key connecting character here is mutual warmbloodedness. The shifting of ...
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... but it seems to actually increase with time. Do formative or guiding principles exist that science does not take into account? The two articles have very different answers. The creative cosmos. "Most people accept without question that the physical world is coherent and harmonious. Yet according to the traditional scientific picture, the Universe is just a random collection of particles with blind forces acting upon them. There is, then a deep mystery as to how a seemingly directionless assembly of passive entities conspire to produce the elaborate structure and complex organisation found in nature." The author of this introductory paragraph, P. Davies, asks, as we all do, "What is the origin of this creative power?" In groping for an answer, he presents first a common example of "blind" organization: the hexagonal convection cells in a pan of heated water. Using for a stepping stone the cooperative action of atoms in a laser, he leaps to the development of an embryo from a single strand of DNA! All such systems are "open"; that is, energy can flow in and out. They are also nonlinear, which means that chaotic, unpredictable action may occur. Davies implies that such action can be "creative," almost as if they possessed free will! His final example is that of the network with large numbers of interacting sites or nodes. With random inputs, large networks do exhibit self-organization. Network theory is now very popular in the field of artificial intelligence. (Remember the computer Hal in 2001?) Davies's conclusion: ...
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... Popper now supports Darwinism. Still more recently, Popper gave the first Medawar Lecture at the Royal Society; and he had something for both sides. How can this be? First, for those who do not know of Sir Karl Popper, we should state that his philosophical views carry considerable weight in scientific circles. He has described how science should work and how its hypotheses should be tested. In this sense, he has defined what is scientific and what isn't . Now, back to the Medawar Lecture, as recounted by M. Perutz. Popper declared his detestation of determinism in all its guises. "Popper disputes the existence of historical laws and holds that our future is in our own hands." Zeroing in on evolution, Popper accepts Darwinism in the sense that "organisms better adapted than others are more likely to leave offspring." He then splits Darwinism into passive and active forms. His passive variety of evolution is that which is currently in vogue -- the deterministic view that random mutation combined with natural selection invariably leads to higher forms of life. But, as already stated, Popper hates determinism and believes that deterministic mechanisms are noncreative. They lead only to deadends. Instead, he prefers "active" Darwinism in which the "idiocyncracies of the individual have a greater influence on evolution than natural selection" and that "the only creative activity in evolution is the activity of the organism." There you have it! Whose side is Popper on? Does it really matter? (Perutz, Max; "A New View of Darwinism," ...
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... depths at Site P28. The concentration and diversity of microorganisms (mostly bacteria) at depths as great as 520 meters (1610 feet) below the ground's surface are remarkably high. It makes one wonder what will be found even farther down. To illustrate, more than 3000 different microorganisms have been found in the boreholes. Many of the bacteria are new to science. As the following two paragraphs demonstrate, subterranean life consists of many well-adapted microorganisms working together. "The traditional scientific concept of an abiological terrestrial subsurface is not valid. The reported investigation has demonstrated that the terrestrial deep subsurface is a habitat of great biological diversity and activity that does not decrease significantly with increasing depth. "The enormous diversity of the microbiological communities in deep terrestrial sediments is most striking. The organisms vary widely in structure and function, and they are capable of transforming a variety of organic and inorganic compounds. Regardless of the depth sampled, the microorganisms were able to perform the cycling of carbon, nitrogen, sulfur, manganese, iron, and phosphorous. Although the organisms were not of the same physiological types, each niche contained a basic cast of microbiological players capable of these nutrient transformations. Such versatility is surprising, and contrary to traditional thinking in soil microbiology, because the deep subsurface is presumably a nutrientlimited environment where photosynthesis and photosynthates are not abundant." The scientists writing this article speculate that similar microorganisms could well be prospering far below the Martian surface, where they are sheltered from radiation and the cruel surface environment. (Fliermans, Carl B., and Balkwill, David ...
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... Science Frontiers ONLINE No. 127: Jan-Feb 2000 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Throat-Singing Humans are born with one organ that is capable of astonishing performances that greatly exceed what is required for the tracking of animals and the grubbing of edible roots. This is the human brain, of course. Not as widely appreciated for its versatility is the human vocal tract. It can generate much more than brute grunts. It renders operatic arias of great beauty and frequency range. The vocal tract can do even more than that; it can carry two musical lines simultaneously. This skill is called "throat-singing" or "overtonesinging." The best-known throat-singers live in the Tuva region of southern Siberia. The semi-nomadic herders of this wild region were evidently inspired to develop throat-singing so that they could better mimic the sounds they heard in nature: the singing of birds, the wind, the sounds of insects. Throat-songs have two components. The first is at a low, sustained fundamental pitch, which can be likened to the drone of a bagpipe. The second, superimposed on the low drone, is a succession of flute-like sounds that resonates high above the drone. It is the second component that can be controlled so as to mirror natural sounds. The result is like nothing Mozart or Verdi conceived. But it is an art form valued in Tuva and a talent rather remarkable from a biologist's perspective. One should compare the vocal ...
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... Science Frontiers ONLINE No. 57: May-Jun 1988 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Living stalactites! subterranean life! (in three parts)Translation of the Introduction of an article from Science et Vie : "One has always held that the calcareous concretions in caves are the work of water and the chemical constituents of the rock. Surprise! The true workers in the kingdom of darkness are living organisms." It's all true. All the references we have state unequivocally that stalactites and stalagmites are created by dripping water that is charged with minerals, calcium carbonate in particular. That stalactites contain crystals of calcite is not denied in the Science et Vie article. Indeed, an electron micro scope photograph shows them clearly; but it also shows that a web of mineralized bacteria is also an intergral part of the stalactite's structure. Laboratory simulations have shown that microorganisms take an active role in the process of mineralization. (Dupont, George; "Et Si les Stalactites Etaient Vivantes?" Science et Vie , p. 86, August 1987. Cr. C. Mauge.) Besides being a surprising adjustment of our ideas about stalactite growth, the recognition that microorganisms may play an active role in the subterranean world stimulates two new questions: (1 ) Can we believe any longer that stalactite size is a measure of age, as is often claimed? (2 ) Is the immense network of known caves (some as long as 500 kilometers) the consequence only of chemical actions? It turns ...
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... with cells to form flagella and cilia. These three "mergers" provided cells with metabolism, photosynthesis, and mobility. Margulis and Sagan obviously do not believe that the "bacterial connection" ended there. They bring their article to a close with an almost poetic manifesto that we now quote in part. The context of the quotation is their assertion that plant and animal evolution would never have taken place unless one life form attacked another and the latter defended itself, all this followed by accomodation and the development of a symbiotic relationship. "Uneasy alliances are at the core of our very many different beings. Individuality, independence -- these are illusions. We live on a flowing pointillist landscape where each dot of paint is also alive. Earth itself is a living habitat, a merger of organisms that have come together, forming new emergent organisms, entirely new kinds of 'individuals' such as green hydras and luminous fish. Without a a life-support system none of us can survive. It is in this light that we are beginning to see the biosphere not only as a continual struggle favoring the most vicious organism but also as an endliess dance of diversifying life forms, where partners triumph." (Sagan, Dorion, and Margulis, Lynn; "Bacterial Bedfellows," Natural History, 96:26, March 1987.) Comment. One should observe that there is a strong connection between the Gaia concept of a living planet and the theory of symbiotic evolution. Strong philosophical statements are also inherent in this outlook on life and its development. For example, individuality ...
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... Science Frontiers ONLINE No. 41: Sep-Oct 1985 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Genetic Garrulousness It is tempting to predict that those cells with the most genetic material will belong to the most advanced organisms. One would, for example, expect to find more DNA or nucleotide pairs in human cells than the cells of bacteria or plants. In the case of the bacteria, this expectation is realized. Some plants, however, have one hundred times more DNA per cell than humans. Some fish and salamanders do, too. One reason why there is no simple relationship between a cell's genetic complement and the organism's complexity is that a lot of genetic material is apparently useless, with no known functions. Human genes, by way of illustration, possess about 300,000 copies of a short sequence called Alu. The Alu sequences seem to be simply dead weight -- functionless -- yet continuously reproduced along with useful sequences. One purposeless mouse gene sequence is repeated a million times in each cell. (Stebbins, G. Ledyard, and Ayala, Francisco J.; "The Evolution of Darwinism," Scientific American, 253:72, July 1985.) Comment. Why so much redundance? Or is there some purpose for this excess genetic material that we haven't yet descried? The "useless" sequences may merely be left over from ancient gene shufflings; or they may be awaiting future calls to action. The above tidbits come from a long review article that is ...
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... Science Frontiers ONLINE No. 48: Nov-Dec 1986 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Oil, oil: everywhere, every age Geologists have discovered a major deposit of oil in Precambrian rocks in Australia's Northern Territory. Precambrian oil does exist elsewhere -- around the Great Lakes, Russia, etc. -- but the Australian deposits differ in that they are economically attractive. The oilbearing strata are dated at between 1.4 and 1.7 billion years; and the oil itself is at least this old. Significantly, the oil contains extremely small amounts of steranes, which are thought to be derived from advanced organisms, but there were plenty of chemicals typical of primitive bacteria. The mere existence of commercially exploitable deposits of Precambrian oil implies that, far from being devoid of life, the ancient earth was host to immense accumulations of bacteria and other simple organisms. (Anonymous; "Ancient Oil in Australia: A New Bonanza?" New Scientist, p. 26, September 11, 1936.) Comment. As discussed above this Australian oil might have been produced abiogenically. The surface and near-surface Athabasca oil sands in western Canada constitute a well-known deposit of almost unbelievable size. Geologists have long speculated about where such an immense quantity of biological matter could have originated. (Few dare to suggest nonbiological origins!) Now, we learn that below the Cretaceous Athabasca oil sands lies a 70,000 square kilometer "carbonate triangle" estimated to contain about 2 x 1011 cubic meters ...
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... microevolution"). J.A . Shapiro, a professor at the University of Chicago, is searching for a "third way," a scientific, non-Darwinian way. Shapiro maintains that five decades of genetic and molecular-biology research have transformed our vision of life. Ile compares the conceptual changes to those accompanying the transition from classical physics to relativity and quantum mechanics. This new theory of evolution -- his "third" way -- will emerge from the convergence of biology and information science. Genomes, asserts Shapiro, are not really the static "beads on a string" envisioned by the Darwinians. Rather, they are fluid and complex. Genes are now seen as multipurpose elements that turn on and off as required for the survival and well-being of the organism they belong to. In this paradigm-eroding paper (referenced below), Shapiro describes four categories of molecular discoveries that have revised our thinking about how evolution works: (1 ) Genome Organization; (2 ) Cellular-Repair Capabilities; (3 ) Mobile Genetic Elements and Natural Genetic Engineering; and (4 ) Cellular Information Processing. He then writes: The point of this discussion is that our current knowledge of genetic change is fundamentally at variance with neo-Darwinist postulates. We have progressed from the Constant Genome, subject only to random, localized changes at a more or less constant mutation rate, to the Fluid Genome, subject to episodic, massive and non-random reorganizations capable of producing new functional architectures. Inevitably, such a profound advance in awareness of genetic capabilities ...
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... Science Frontiers ONLINE No. 67: Jan-Feb 1990 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects We Live Atop A Chemical Retort Far down there beneath our feet, the earth's chemicals are bubbling away, aided often by bacteria and other life forms. It's a dark world, but it's also hot, permeated by fluids, and possibly the abode of organisms we haven't dreamed of. Three hints of this nether world follow. Quick oil. Rather than ripening in deep strata for millions of years, as per prevailing theory, some oil is being created in only a few thousand years in the vicinities of ocean-bottom chimneys. Dimesized oil globules have been sighted floating near these chimneys. Analysis of chunks broken off the chimneys by research submersibles reveal the presence of petroleum-like hydrocarbons that are less than 5000 years old. It is thought that high-temperature fluids percolating up through the sediments convert buried organic matter into oil very rapidly. (Monastersky, R.; "The Quick Recipe for a Soup of Black Gold," Science News, 136:295, 1989.) Comment. Not mentioned in this article is T. Gold's theory that oil is actually derived from primordial carbon deep in the crust. Gassy water. Some water wells in Texas also produce much methane. This methane is apparently not related to any oil or gas wells in the region. Rather, surmise has it that bacteria deep in the crust are converting buried organic material into methane and ...
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... Science Frontiers ONLINE No. 41: Sep-Oct 1985 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Evolution's motor runs fast and quietly M. Kimura has been promulgating what he terms The Neutral Theory of Evolution. He concludes that "the most prev-alent evolutionary changes that have occurred at the molecular level, that is in the genetic material itself, since the origin of life on Earth are those that have been caused by random genetic drift rather than by positive Darwinian selection." Kimua maintains and can experimentally prove to some extent that the genetic material of all organisms changes rapidly and constantly. The genes change much more rapidly than scientists believed just a few years ago. We observe few if any changes at the phenotype level (organism morphology) because the overwhelming majority of these changes are neutral. They confer no significant advantage or disadvantage on the organism. In fact, Kimura and others have demonstrated that the fastest molecular evolution occurs in the least important genes. It is fastest of all in the pseudogenes or dead genes, which seem to have no discernable functions. In other words, the genetic engine is running, but the gears are in neutral! In Kimura's thinking, these molecular changes may eventually become important at the phenotype level if the environment changes or there is some other destabilizing influence. Kimura is the author of the 1983 book The Neutral Theory of Molecular Evolution. Although Kimura has some experimental support, his theory is not widely accepted. (Motoo Kimura; "The Neutral Theory of Molecular ...
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... Science Frontiers ONLINE No. 57: May-Jun 1988 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Does the aids virus really cause aids?All but a tiny minority of scientists accept as fact that an organism called the human immunodeficiency virus (HIV) is the cause of AIDS. This fact is hallowed and defended as vigorously as the facts of evolution, the Big Bang, and continental drift. Extremely nasty things are being said about a handful of heretics who attack this position. "One leading dissident, UC Berkeley molecular biologist Peter H. Duesberg, believes that HIV is not the cause of AIDS -- at least not the sole cause. "He thinks the virus may be an opportunistic organism that found a willing host in the AIDS patient who became sick from something else. That is, he believes HIV is the result of the disease, not the cause. Duesberg thinks the cause of AIDS has more to do with the life style of most of the AIDS patients, but he admits that he doesn't know exactly what." Duesberg points out that three things must be true before a microorganism can be blamed for causing a disease. These are called Koch's Postulates, after R. Koch, who formulated them a century ago: Every patient who has the disease must also harbor the suspected microorganism. Some AIDS sufferers do not have the AIDS virus, although it is debated whether as many as half don't or very few don't . The microorganism must cause the disease when ...
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... Science Frontiers ONLINE No. 48: Nov-Dec 1986 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Geophysiology The concept of the earth-as-an-organism -- the so-called Gaia hypothesis -- keeps popping up. We now have an excellent progress report on current Gaia research; e.g ., the Daisyworld model; by J.E . Lovelock. He defines Gaia in an early paragraph: "In the early 1970s, Lynn Margulis and I introduced the Gaia hypothesis. It postulated the earth to be a self-regulating system comprising the biota and their environment, with the capacity to maintain the climate and the chemical composition at a steady state favorable for life." L. Margulis is an author of Micro-Cosmos and a champion of evolution-via-endosymbiosis; that is, diverse organisms uniting to create new species. Going back to Lovelock's review, there is little that is anomalous on a small scale. Of course, on a large-scale, the data supporting the concept of life-as-a -whole manipulating the atmosphere, oceans, etc., to perpetuate and perhaps improve itself are highly anomalous, because the Gaia hypothesis is far out of the scientific mainstream. (Lovelock, James E.; "Geophysiology," American Meteorological Society, Bulletin, 67:392, 1986.) Comment. Our secret purpose here is to use the Lovelock article as an excuse to out-Gaia Gaia! Lovelock's article plus those preceding on ...
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... Science Frontiers ONLINE No. 110: Mar-Apr 1997 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Martian Life: Act Ii The final issue of New Scientist for 1996 carried an article entitled "Death Knell for Martian Life." Was all that media hype for naught? What will NASA do now? Wait! Another putative Martian rock may save the day. Picked up in Antarctica in 1974, meteorite EETA 79001 weighs 7.9 kilograms and is superficially unimpressive. Inside, though, researchers I.P . Wright and C.T . Pillinger found a surprising quantity of organic compounds -- actually 1.5 parts per thousand by mass. This fraction is so large that terrestrial contamination seems remote. Furthermore, the organic component contains 4% more carbon-12 (relative to carbon-13) than the adjacent carbonate minerals. This is strong evidence that the organics had a biological origin. Similar tests on the media-hyped Martian meteorite ALH 84001 yielded the same carbon ratios. Pillinger remarked: "These results offer the strongest support yet for the hypothesis that life once existed on the planet." So far so good, but EETA 79001 conveys two additional facts -- both very tantalizing: (1 ) This meteorite was blasted off the Martian surface only about 500,000 years ago; and (2 ) It probably came from a different hemisphere than ALH 84001. From all this, a somewhat shaky conclusion: Life on Mars existed not only recently (and perhaps is still present) but was ( ...
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... 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 The star of the star-nosed mole (Left) Tenticle-like rays surrounding one nostril of the star-like mole. (Right) The number of rays around the other nostril give the density of sensory receptors. The star-nosed mole is one of North America's more bizarre mammals. Its nostrils are surrounded by mobile, Medusa-like appendages that are richly suppled with nerves and blood vessels. These tentacle-like structures form the "star," which has long been considered a tactile organ used for feeling for prey. However, behavioral experiments by E. Gould et al indicate that the star may be more than a tactile organ. It seems to sport electrical sensors that detect the minute electrical fields surrounding worms, leeches, insect larvae, and other favorite mole tidbits. This conclusion derives from experiments in which starnosed moles preferentially attacked the parts of worms that are most strongly electrical. Actually, scientists have been puzzled as to how this mole found its prey, for this mammal is semiaquatic and somehow locates its dinner in muddy water even though it has poor eyesight. Although some fish possess electrical sensors, they are uncommon in mammals. Half way around the planet, another strange creature, also classified with the mammals, frequents muddy waters looking for the same sort of prey favored by the star-nosed mole. The Australian platypus also has weak vision and employs search techniques similar to those of ...
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