Science Frontiers
The Unusual & Unexplained

Strange Science * Bizarre Biophysics * Anomalous astronomy
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About Science Frontiers

Science Frontiers is the bimonthly newsletter providing digests of reports that describe scientific anomalies; that is, those observations and facts that challenge prevailing scientific paradigms. Over 2000 Science Frontiers digests have been published since 1976.

These 2,000+ digests represent only the tip of the proverbial iceberg. The Sourcebook Project, which publishes Science Frontiers, also publishes the Catalog of Anomalies, which delves far more deeply into anomalistics and now extends to sixteen volumes, and covers dozens of disciplines.

Over 14,000 volumes of science journals, including all issues of Nature and Science have been examined for reports on anomalies. In this context, the newsletter Science Frontiers is the appetizer and the Catalog of Anomalies is the main course.


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Compilations of back issues can be found in Science Frontiers: The Book, and original and more detailed reports in the The Sourcebook Project series of books.


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... Science Frontiers ONLINE No. 25: Jan-Feb 1983 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Promiscuous Dna The cells of plants (photosynthetic eukaryotes) are genetically the most complex that biologists have discovered. Each cell has three genetic systems: its own, that of the chloroplasts; and that of the mitochondria. It is supposed that the chloroplasts and mitochondria were once free-living cells that linked up with the embryonic plant cell to form a symbiotic partnership, with the host "plant" cell being the dominant member. Up until now, the three genetic systems were thought to be discrete, each going down its own pathway. But chloroplasts genes have now been found inside plant mitochondria, overturning conventional wisdom. To sum it all up, DNA seems promiscuous -- no respecter of privacy and breaking down all isolating genetic barriers. This discovery at once raises a dozen questions. For example, are mitochondria genes in chloroplast cells? How far does this promiscuity go? Can the same thing happen in higher organisms; say, with humans and symbiotic microorganisms or even not-so-symbiotic disease organisms? Is there no stopping this DNA? (Ellis, John; "Promiscuous DNA -- Chloroplast Genes inside Plant Mitochondria," Nature, 299:678, 1982.) From Science Frontiers #25, JAN-FEB 1983 . 1983-2000 William R. Corliss ...
Terms matched: 1  -  Score: 65  -  15 May 2017  -  URL: /sf025/sf025p06.htm
... Science Frontiers ONLINE No. 34: Jul-Aug 1984 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Dna Even More Promiscuous It was a surprise when DNA sequences from mitochondria in yeast cells were discovered setting up shop in the nuclear genomes (i .e ., the normal genetic endowment of the cell nucleus). Now biologists find that DNA sequences in many species regularly and frequently hop from one genome to another. Genetic material from cell chloroplasts mix with that of the mitochondria and that of the normal nucleus in what seems to be a free-for-all. This genome hopping has earned DNA the adjective "promiscuous." The significance of DNA promiscuity is to be found in the general belief that the cell's mitochondria and chloroplasts were once independent biological entities that, in the course of life's development, invaded or were captured by cells and have led a symbiotic life ever since. The mitochondria and chloroplasts perform certain important functions in the cell but were thought, until now, to retain considerable genetic independence. (Lewin, Roger; "No Genome Barriers to Promiscuous DNA," Science, 224:970, 1984.) Comment. The promiscuity of DNA raises speculation that other DNA-bearing entities that invade the body, especially the viruses, may transfer their DNA to the host, and conceivably vice versa. With DNA apparently much more promiscuous than believed earlier, the role of disease in the development of life takes on a new importance. In other words, all species can potentially exchange genetic ...
Terms matched: 1  -  Score: 34  -  15 May 2017  -  URL: /sf034/sf034p10.htm
... Science Frontiers ONLINE No. 51: May-Jun 1987 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Evolution Through Mergers The overview in Natural History describes how, in theory, the mitochondria in cells were created by bacterial invasion. The presence of chloroplasts in plants, too, may have come about in this way. A case also exists for the alliance of spirochetes 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 ...
Terms matched: 1  -  Score: 15  -  15 May 2017  -  URL: /sf051/sf051b09.htm
... onto and destroy. The "fittest" defensive cells are those that have just the right characteristics to knock off invaders, and only they survive permanently in the body's defensive arsenal, giving it acquired immunity. The Lamarckian part of this story occurs when the RNA of the selected defensive cells gets passed on to the organism's progeny. (Tudge, Colin; "Lamarck Lives -- In the Immune System," New Scientist, 89:483, 1981.) Comment. The picture evolving here is one of a hierarchy of evolutionary struggles -- say, humans on one level and their contained defensive cells on another level. The levels are not completely independent. The question that arises next is whether there are other evolutionary struggles going on, possibly in the mitochondria and chloroplasts, which possess their own genetic material. Or, waxing speculative, are there hierarchies of evolutionary struggle above humanity of which we know nothing except for perhaps a few anomalies representing cross talk between levels? From Science Frontiers #15, Spring 1981 . 1981-2000 William R. Corliss ...
Terms matched: 1  -  Score: 14  -  15 May 2017  -  URL: /sf015/sf015p09.htm
... of the cells of a parasite that preys on the cells of red algae. Two such cells abut the parasitic filament. The small black circles are parasitic cell nuclei which, when confronted with a red alga cell, become wrapped in small "conjuctor cells" which are then somehow transferred to the host cell on the right. The actual transfer involves the formation on the host cell wall of a sort of dimple called a "secondary pit connection." (Why this forms is not known.) Once inside the host cell, the parasite nucleus and/or the cytoplasm transferred with it dramatically reprograms host cell operations. The host cell shifts into highgear food production, enlarging up to twenty times its normal size. The host cell wall thickens, its nuclei (large black circles) and chloroplasts multiply. Adjacent cells (left) remain unaffected. (Lewin, Roger; "New Regulatory Mechanism of Parasitism," Science, 226:427, 1984.) Comment. It is one thing for external stresses to stimulate cell reprogramming, but quite another when another species inserts its programs into those of the host. Is this another way of producing "hopeful monsters?" A parasitic filament growing between host cells, showing how parasite nuclei are first enclosed in bud-like conjunctor cells and then inserted into the host cell. From Science Frontiers #37, JAN-FEB 1985 . 1985-2000 William R. Corliss ...
Terms matched: 1  -  Score: 14  -  15 May 2017  -  URL: /sf037/sf037p09.htm
... 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 "evolution from outer space." Hoyle believes that microorganisms and other biological information are transported in cosmic debris. Finally, the story of Lynn Margulis' uphill fight against scientific skepticism is related in: (Keller, Evelyn Fox; "One Woman and Her Theory," New Scientist, p. 46, July 3, 1986.) Serial symbiosis; bacterium to alga to alga; may have led to chloroplasts. From Science Frontiers #47, SEP-OCT 1986 . 1986-2000 William R. Corliss ...
Terms matched: 1  -  Score: 14  -  15 May 2017  -  URL: /sf047/sf047p08.htm
... contents will mix. The once-independent and widely different cell nuclei will fuse, forming a single hybrid cell with a common membrane. Even more astonishing, this totally new biological entity will often divide and produce an endless line of the new hybrid. As might be expected, some hybrids do not remain true and revert to one or the other of the original species. Although cell fusion has been observed only under laboratory conditions, it seems to represent a near-universal cell phenomenon that might be realized rarely under natural conditions. The implications for the history of life are far-reaching. For example, the mitochondria in human cells that help our bodies use oxygen to obtain energy may well be descendants of bacteria that once fused with primitive cells. The same may be true for the chloroplasts in plant cells. (Thomas, Lewis; "Cell Fusion: Does It Represent a Universal Urge to 'Join Up'?" Science Digest, 86:52, December 1979.) Comment. Natural cell fusion might make large evolutionary steps possible and be much faster than endless small genetic changes. Are we all composite creatures? From Science Frontiers #10, Spring 1980 . 1980-2000 William R. Corliss ...
Terms matched: 1  -  Score: 13  -  15 May 2017  -  URL: /sf010/sf010p05.htm
... . 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! Is not all life implicitly encoded in the properties of the most fundamental particles? If not, reductionism is a lie. From Science Frontiers #11, Summer 1980 . 1980-2000 William R. Corliss ...
Terms matched: 1  -  Score: 13  -  15 May 2017  -  URL: /sf011/sf011p04.htm

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