24 results found.
... Science Frontiers ONLINE No. 111: May-Jun 1997 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects 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 ...
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... Science Frontiers ONLINE No. 45: May-Jun 1986 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Scant Ant Chromosomes The Australian ant Myrmecia pilosula, called the "bulldog ant" because of its viciousness, carries all its genetic information in a single pair of chromosomes. (Males are haploid and have just one chromosome.) Although classified as a "primitive" ant, the bulldog ant exhibits complex social behavior and is obviously far from a simple biological entity. Biologists were therefore surprised to find all genetic instruction residing in a single chromosome pair. Social insects tend to have higher chromosome numbers. It is also interesting that Myrmecia pilosula, originally described as a single species, actually consists of several distinct sibling species with chromosome numbers (i .e ., pairs) of 9, 10, 16, 24, 30, 3l, and 32. Yet, they all look pretty much alike. (Crosland, Michael W.J ., and Crozier, Ross H.; Myrmecia pilosula, an Ant with Only One Pair of Chromosomes," Science, 23l:1278, 1986.) Comment. Chromosome number or the sheer quantity of genetic material seems poorly correlated with biological complexity. From Science Frontiers #45, MAY-JUN 1986 . 1986-2000 William R. Corliss ...
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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 The Chromosome Gap "Compared with the chromosomes of humans and other great apes, the pygmy chimpanzee's chromosomes are .. .the most specialized -- they have changed more over time than have the others. 'Surprisingly,' Stanyon and his colleagues conclude, 'the human karotype (chromosome complement) is the most conservative...It has more unchanged chromosomes." (Anonymous; "Chromosomes Show Apes 'More Evolved' Than Man," New Scientist, p. 24, July 17, 1986.) From Science Frontiers #47, SEP-OCT 1986 . 1986-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 122: Mar-Apr 1999 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects A Genetic Disconnect Bandings on chromosome 9 from humans (H ), chimpanzees (C ), gorillas (G ), orang-utans (O ) If human and chimpanzee nuclear DNAs differ by only 1.5 %, why are the two species so profoundly different in anatomy and behavior? The obvious external differences are body hair, the use of language, the method of locomotion, and of course culture. Less well known is the fact that humans are more susceptible to diseases like as cancer and AIDS. Apparently, superficial comparisons of DNAs slough over genetic details that result in major differences in the living animals. Some of the genetic differences between humans and chimps seem to belie that miniscule 1.5 % difference everyone bandies about. To illustrate, humans have only 46 chromosomes, while the great apes all have 48. The 1.5 % figure doesn't hint at this significant difference. Next, take a look at chromosome #9 in humans and the great apes. Chromosome bandings are different enough to raise further suspicions about the 1.5 % figure. (Gibbons, Ann; "Which of Our Genes Make Us Human?" Science, 281:1432, 1998.) Comments. It is easy to see how gross comparisons of DNA might miss important details. The popular "DNA-hybridization" method simply mixes together strands of DNA from the two species being compared. These are allowed ...
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... Lunar Phase BHF26 Anomalous Variations in Twin and Multiple Births BHF27 Extremely Rapid Growth in Children BHF28 Human Thermal Control: A Uniquely Bad Design BHF29 Colored Perspiration BHF30 Emotion-Stimulated Tears BHF31 The Lack of Any Measurable Biochemical Value of Sleep BHF32 Lunar Control of the Sleep Cycle BHF33 Voluntary Suspended Animation BHF34 Human Mortality Correlated with Geomagnetic Activity BHF35 Nearly-Simultaneous Deaths of Twins BHF36 Curious Attitudes after Death Geophagy in Pregnancy and Health Evolution of Menopause Uncertain Purpose of REM Sleep Curious Nature of Anesthesia Evolution of Menstruation Fetal Growth Correlated with Solar Activity Evolution of Sex Purpose of Life after Menopause Decline in Sperm Counts Fetus Signals Timing of Birth How Embryo Development Is Controlled and Effected Cycles in Autistic Births Rhythms in Growth Evolution of Lactose Tolerance Twins and Occurrence of Nightmares Timing of the End of Sleep BHG HUMAN GENETICS BHG1 Human Chromosomes Less Evolved Than Ape Chromosomes BHG2 The Presence of Introns in Human Chromosomes BHG3 Human Chromosomes Lack the "Baboon Marker" BHG4 Y-Chromosome Analysis Suggests First Humans Were Pygmies BHG5 Human and Ape Chromosome Numbers Differ BHG6 Identical Twins May Have Different Genomes BHG7 Gene Imprinting: Parental Influence on Genes BHG8 The Accentuation of Inherited Traits in Succeeding Generations BHG9 Higher Variability of Mitochondrial DNA in Subsaharan Africans BHG10 Mitochondrial DNA Evolves Much Faster Than Nuclear DNA BHG11 Disparity between Human and Ape Phenotypes and Genotypes BHG12 Chimpanzee Mitochondrial DNA More Diverse Than That of Humans BHG13 Human Mitochondria Radically Different from Those of Other Organisms BHG14 Paternal Mitochondrial DNA can Be Inherited BHG15 African Nuclear DNA Is Distinct from That of Other Populations BHG16 Chromosome Banding Analysis Incompatible with DNA Analysis BHG17 Involucrin Analysis Conflicts with Mitochondrial DNA Analysis BHG18 Human Molecular Clocks Run ...
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... Science Frontiers ONLINE No. 116: Mar-Apr 1998 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The Ultimate In Unisex At the Western General Hospital in Edinburgh, doctors have been examining a "boy" with an ovary and a fallopian tube instead of a left testicle. Part of "his" body's cells are male (one X and one Y chromosome), part female (two X chromosomes). This hermaphrodite-like condition apparently developed because "he" was conceived via in vitro (IVF) fertilization. Probably both a male embryo and a female embryo were transferred to "his" mother's uterus, where they fused and formed a single fetus. (Anonymous; "Two into One," New Scientist, p. 21, January 24, 1998. Cited source: The New England Journal of Medicine, 338:166, 1997.) Comments. We have already cataloged two similar conditions: Human blood-chimeras, where one person has two types of blood due to the absorption of one fetus by its twin, each having different blood types. (BHC15 in Biological Anomalies: Humans II) Birds that are female on one side and male on the other (bilateral gynandromorphism). (BBA1 in our forthcoming Biological Anomalies: Birds) From Science Frontiers #116, MAR-APR 1998 . 1998-2000 William R. Corliss ...
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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 Why conserve junk?A. Jeffries, working at Leicester University with globin genes from man and related primates, has been studying how these genes direct the blood cells to make the alpha and beta chains of hemoglobin. Jeffries' analyses seem to indicate that the genes now coding for these hemoglobin chains are almost identical to those existing in human ancestors some 500 million years ago. Two curious facts have cropped up, however. First, about 200 million years ago, these genes were modified very slightly and relocated to entirely different chromosomes. Second, 95% of the DNA associated with these genes is "junk" -- with no known use. Why did nature conserve junk for 500 million years? Are vital genes in the habit of jumping from one chromosome to another? (Yanchinski, Stephanie; "DNA: Ignorant, Selfish and Junk," New Scientist, 91:154, 1981.) From Science Frontiers #17, Fall 1981 . 1981-2000 William R. Corliss ...
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... cells 27 years after the birth a male child. Evidently, descendents of fetal cells escape during pregnancy and persist in the mother for years after birth. The mother thus becomes a blend of herself and her child (or, possibly, children) - a kind of chimera. The question is: Why doesn't the mother's immune system destroy these foreign cells? Some scientists speculate that these escaped and still-surviving cells may help explain why women are more susceptible than men to autoimmune diseases. (Travis, J.; "Kids: Getting under Mom's Skin for Decades," Science News, 149:85, 1996) Fatherless blood. In Britain, a male child has been found with normal skin, with each cell carrying the expected X and Y chromosomes, but "his" blood is all female. Its cells contain the mother's two X chromosomes with no paternal contribution. What happened? One theory is that the mother's unfertilized egg spontaneously divided. Then, fertilization occurred, but it was only partial. The sperm got to just one of the two or more cells derived from the egg. The embryo continued to develop but it was part all-mother and part mother-father! "Partial parthenogenesis" seems to be the proper term here. The affected "boy" also has noticeably asymmetrical facial features. Since one in every few hundred people display slight facial asymmetry, partial parthenogenesis may be more common than usually thought. (Cohen, Philip; "The Boy Whose Blood Has No Father," New ...
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... Science Frontiers ONLINE No. 47: Sep-Oct 1986 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Explaining the Nazca Lines Humans in the Americas 32,000 Years Ago? Astronomy Lumps, Clumps, and Jumps Clump of Antimatter 1986: "Tired Light" Revived Again Biology Something Big Down There! Brain Architecture: Beyond Genes Heretical Evolutionary Theory The Chromosome Gap How the Cheetah Lost its Stotts Earth's Womb Geology Oil & Gas From the Earth's Core Oceans From Outer Space? Continental Graveyard? Two Points of Great Impact Geophysics A True Fish Story Booming Dunes Another Luminous Aerial Bubble Psychology Magnetic Theory of Dowsing Chemistry & Physics Unpredictable Things ...
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... Science Frontiers ONLINE No. 111: May-Jun 1997 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Ancient entertainments Tobacco and cocaine in ancient egypt An anasazi ley line? Astronomy Extraterrestrial handedness Biology Circaseptennial rhythm in ear growth Life on different scales Chromosome choreograph Is perfect pitch favored by natural selection? Carnot creatures Geology Methane burps and gas-hydrate reservoirs Why some sands sing, squeak, and boom Geophysics White streak from a tv set Exotic seismic signals Psychology Malleable memories Math & Physics Levitation and levity! Something strange is going on! ...
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... Science Frontiers ONLINE No. 8: Fall 1979 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The Importance Of Nonsense One of the greatest surprises of modern molecular biology has been the discovery of "split genes" in higher forms of life. In the chromosomes of lowly bacteria, genes march along one behind the other, but in more complex organisms the genes are separated by segments of genetic material that apparently have nothing to do with the manufacture of protein. Because there seems no need for these inserted jumbles of genetic information, they are characterized as "nonsense." But evolutionists insist that this nonsense must have some survival value or it wouldn't be there! Present speculation is that the nonsense segments separate mini-genes that contain the blueprints for assembling well-defined parts of proteins that possess specific functions. To illustrate, the main part of the immunoglobulin molecule has four functional parts (one for interacting with cell membranes, another that functions as a hinge, and so on). Lo and behold, the immunoglobulin gene consists of four mini-genes separated by three segments of nonsense. The suspicion is that the evolution of higher life forms has been accelerated by keeping these prefabricated, functionally oriented mini-genes apart and shuffling them as integral units. The shuffling of entire functional elements rather than smaller bits and pieces of genetic information might speed up organic evolution. (Lewin, Roger; "Why Split Genes?" New Scientist, 82:452, 1979.) From Science Frontiers #8 , Fall 1979 . ...
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... Science Frontiers ONLINE No. 132: NOV-DEC 2000 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Unidentified Cellular Object The multitudinous cells that make up our bodies are miniscule factories humming with activity. The microscope reveals mitochondria, chromosomes, centrioles, granules, and a host of entities doing their own things. But even after generations have scrutinized our cells, new objects are discovered. The latest, only recognized in 1986, look like a miniature hand grenades. Called "vaults" these objects are composed of proteins and ribosomal DNA. They exist only in the cells of the higher organisms -- like us. Biologists surmise that they are important in some way but have no idea what they do. (Anonymous; "Cell Biology Mystery," Science, 289:355, 2000.) A "vault," a mammalian cellular object of unknown purpose. From Science Frontiers #132, NOV-DEC 2000 . 2000 William R. Corliss Other Sites of Interest SIS . Catastrophism, archaeoastronomy, ancient history, mythology and astronomy. Lobster . The journal of intelligence and political conspiracy (CIA, FBI, JFK, MI5, NSA, etc) Homeworking.com . Free resource for people thinking about working at home. ABC dating and personals . For people looking for relationships. Place your ad free. ...
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... Science Frontiers ONLINE No. 159: May - Jun 2005 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Incredible Discoveries in Mexico The Too-Ancient Human tools at Valesquillo Reservoir What the Polynesians Brought and What they tool Away Astronomy Rewriting Mars' History Again, Again, Again What's the Matter with Matter? Biology Rover's Leap Be Late and It's All Over between Us! Pleistocene Hanky-Pank? The Inversion of Chromosome 17 Geology Bot a Subtle Signal! Deep-Earth Methane Generation Geophysics Extreme LDEs (long-Delayed Echos) Unclassified 13 Things that don't make sense A Very High Satellite Some very Low Satellites? ...
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... Science Frontiers ONLINE No. 22: Jul-Aug 1982 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The Nomads Within Us It was originally believed that human chromosomes were fixed at conception and all subsequent organic development proceeded from the instructions encoded on them. Biologists have recently discovered that genes grasshopper about, constantly modifying genetic instructions -- at least that's the current thinking. Additional modification of genetic instructions seems to be accomplished by entities called "nomads" or "mobile dispersed genetic elements." One type of nomad is a simple ring of DNA called a plasmid. Plasmids seem to be identical to a kind of virus called a retrovirus, which can penetrate into cells and tamper with gene expression; that is, the way genetic instructions are interpreted. Plasmids have been discovered in maize, fruit flies, bacteria, and, now, humans -- and healthy people at that. No one is quite sure what these plasmids do. Even though they look like retroviruses, they may not be associated with illness, but rather help organisms adapt to changing environments. But no one really knows. (Anonymous; "Human Wandering Genes Can Live on Their Own," New Scientist, 94:18, 1982.) Comment. So, the human body is not only beset by new genetic instructions and the static introduced by invading viruses and other disease agents, but it has an indigenous population of nomads continually fiddling with our cells' genetic instructions. Our bodies seem more like Grand Central Station with trains loaded with new biological ...
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... Science Frontiers ONLINE No. 45: May-Jun 1986 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology The Lost City of Nan Madol Bubonic Plague As An Indicator of Diffusion? The Rabbit in the Moon: More Evidence of Diffusion? Astronomy The Martian Great Lakes Antarctic Meteorites Are Different Disparity Between Asteroids and Meteorites Biology The Gulper Eel and its Knotty Problem Bats May Have Invented Flight Twice (At Least!) Scant Ant Chromosomes Champ in 1985 Platypus Bill An Electrical Probe Polar Bear Coats Are Thermal Diodes Geology When Antarctica Was Green Wrong-way Primate Migration Eastern Quakes May Be Lubricated by Heavy Rainfalls The Exploding Lake Backtracking Along the Paluxy: Or is There A Deeper Mystery? Geophysics Electromagnetic Radiation From Stressed Rocks Some English Meteorological Anomalies Ozone Hole Over Antarctica Psychology Be Happy, Be Healthy: the Case for Psychoimmunology ...
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... health histories, and other factors are often eerily the same. For example, two female identical twins, who had never seen each other, each wore eight rings! The upshot of such investigations is that most of a person's characteristics are genetic in origin; that is, Nature dominates nurture. But what about identical twins who are remarkably different? They can, for instance, differ appreciably in size, intellect, and behavior. In such cases, does nurture dominate nature? No! Identical twins may diverge even in the womb, where one may receive more oxygen and nutrients than the other. One also may be assailed in by viruses, bacteria, or drugs, while the other escapes. Even more drastic is the possi bility that one twin may pick up an extra chromosome soon after the original egg has split. Also, mutations may doom one twin to Down's syndrome or some other genetic affliction, while the other is unscathed. Identical twins may even be of different sex! Of course, such twins are genetically different, but they are still monozygotic (from the same egg). Blood tests will show them to be identical. It used to be thought that the small differences that did exist between identical twins separated at birth were surely due to nurture, not nature. But, considering all the differences that can accrue in, it seems that the role of nurture in shaping individuals is much smaller than thought, possibly negligible. (Horgan, John; "Double Trouble," Scientific American, 263:25, December 1990.) ...
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... may seen. "Not only are behavioural phenotypes very sensitive to non-genetic influences," writes [R .] Greenspan, "but also the highly interconnected network of the nervous system sets up an additional layer of complexity between the gene and the realization of the phenotype." (Ref. 1) Many genes code for multiple variants of the same protein. And many proteins are modified by adding sugar molecules, which play a big role in determining where proteins go and what they do. What's more, different proteins can join together to carry out completely new functions. (Ref. 2) A group of French biologists, led by Francois Jacob and Jacques Monod showed that the gene's boundaries are fuzzier than had been thought and that genes are not restricted to chromosomes. Recently, biologists have found genes within genes, overlapping genes, and DNA sequences that specify one protein when read "forward" and another when read "in reverse." Muddling things further, the instructions encoded in the DNA do not always reach the ribosome as a literal translation. In a phenomenon known as RNA editing, an enzymatic highwayman intercepts the RNA message en route and alters it, so the resulting protein is not identical to that specified by the DNA. (Ref. 3) We can sum up by saying that a lot can happen to that information encoded in the genome before it is put to use. References Ref. 1. Anonymous; "The Flexible Genome," Nature, 411:xi, 2001. Ref. 2. Coghlan, Andy; ...
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... is taken from a letter to Nature by a "practising geneticist." "In the discussion in your columns about the application of quantitative methodology based on the study of evolutionary processes to the analysis of the development of human culture, there is an unquestioned assumption on both sides of that issue that quantitative theory, as expounded by practitioners such as Fisher, Haldane, Wright, Cavalli-Sforza and Maynard Smith, has been successful in illuminating and explaining the process of biological evolution and the genetic relationships between species. As far as I know, there is no evidence to support this assumption. Indeed, there is a vast number of observations unaccounted for in the extant quantitative evolutionary theories. Many of these observations (inducible mutation systems, rapid genomic changes involving mobile genetic elements, programmed changes in chromosome structure) challenge the most fundamental assumptions which these evolutionary theories make about the mechanisms of hereditary variation and the fixation of genetic differences." (Shapiro, James A.; "Evolution by Numbers," Nature, 303:196, 1983.) Comments. The "observations unaccounted for" are buried in such obscure journals as S.B . ges. Morph. Physio. (Munchen). It is pretty obvious that the Sourcebook Project is just scratching the surface. From Science Frontiers #28, JUL-AUG 1983 . 1983-2000 William R. Corliss ...
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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 Is oliver a "humanzee"?Oliver: male, 30ish, very hairy, height 1.2 meters, weight 50 kilos, erect posture, unusual ears, offensive odor. Oscar always walks on two feet, uses a human toilet (which he flushes), can mix drinks, and enjoys a cup of coffee and a nightcap. Chimps ignore him; humans wonder what he is. Superficially, Oscar is definitely chimp-like; but shave his head and he becomes eerily human. Although Oscar was widely exhibited in the 1970s, his fame diminished in the 1980s. But now, scientists want to count his chromosomes and find out what he really is. One suggestion is a cross between a chimpanzee and a bonobo (a "pygmy chimpanzee"). Or how about a chimp-human hybrid? There have been dark rumors of hushhush experiments in China, Italy, and the U.S . We'll let you know what the geneticists conclude -- unless there is more "hush-hush." (Holden, Constance; "' Mutant' Chimp Gets a Gene Check," Science, 274:727, 1996. Also: Anonymous; "Oo-be-doo, I Want to Be Like You," Fortean Times, no. 95, p. 15, February 1997.) From Science Frontiers #110, MAR-APR 1997 . 1997-2000 William R ...
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... " accompanied by useful responses to challenges that have not yet been posed to the life form in question. This prescience verges on the miraculous to the uninitiated, but mainstream biologists seem content to write the phenomenon off as merely good fortune -- like hitting two jackpots in a row on the same slot machine. A good example of preadaptation occurs when bacteria are cultured in the presence of an antibiotic. Within a few weeks, they have evolved a resistance to that particular antibiotic. This well-known phenomenon is easily explained by evolution. However, often the newly evolved (or "adapted") bacteria are also resistant to several other antibiotics that work by different mechanisms. All of the multiple gene changes needed for the several different defense mechanisms are controlled by a single site on the same chromosome. (Levy, Stuart B.; The Antibiotic Paradox , New York, 1992, p. 99. Cr. A. Mebane.) Comments. How can bacteria prepare defenses against antibiotics they have not been exposed to? Luck, prescience, or some unrecognized mechanism? In his Ever Since Darwin , S.J . Gould acknowledges that "preadaptation implies prescience although in actuality it means just the opposite! His explanation of "preadaptation is not easy to grasp. "In short, the principle of preadaptation simply asserts that a structure can change its function radically without altering its form as much. We can bridge the limbo of intermediate stages by arguing for a retention of old functions while new ones are developing." From Science Frontiers #124, JUL-AUG 1999 . ...
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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 A FAR-WANDERING TRIBE?" The Lemba, a Bantu-speaking people of southern Africa have a tradition that they were led out of Judea by a man named Buba. They practice circumcision, keep one day a week holy and avoid eating pork or piglike animals." As the author of the above words, N. Wade, is quick to point out, there are several other groups of people around the world who practice Judaic rites or claim to be of Jewish ancestry but have no provable ancestral connections. The Lemba, however, also have a genetic tie. Lemba males carry a distinctive set of genetic mutations in their Y chromosomes. This particular genetic characteristic is strongly associated with the cohanim, the Jewish priests said to be descendants of Aaron. This genetic trait is less common among lay Jews (only 3-5 %) and very, very rare among non-Jews. This "cohen genetic" signature (cohen = priest) is considered diagnostic of populations of Jewish ancestry. (Wade, Nicholas; "DNA Confirms Jewish Ancestry of African Tribe," Houston Chronicle, May 10, 1999. Cr. D. Phelps. Anonymous; "DNA Ties African Group to Jews," Chicago Sun-Times , May 10, 1999. Cr. J. Cieciel) From Science Frontiers #127, JAN-FEB 2000 . 1997 William R. Corliss ...
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... Center, operated by F. de Sarre, publishes a little journal called Bipedia . In the first issue of Bipedia , de Sarre sets out, in English, his basic thesis: Abstract. "The explanation of Man's special nature is to be sought in the original combination formed by a primordial brain, the globular form of the skull and initial bipedalism. The ape, when compared with Man, appears to be rather a vestige of Man's ancestral line than his predecessor, according to the views of Max Westenhofer, Serge Frechkop, Klaas de Snoo and Bernard Heuvelmans. The study of the human morphology allows logically to carry the problem of Man's origin back to a very early stage of the evolution, and not to which has been reached by apes. From chromosomal and DNA comparison in the cells of living apes and people, several researches argue to-day that humans are genetically more like the common ancestor than is either Chimpanzees or other apes. The array of facts and considerations should be sufficient for an unbiased mind to discount away any idea of simian antecedents in Man's ascent." The body of the article supports de Sarre's thesis with observations from embryogenesis, comparative anatomy (skull, hand, foot), and phylogenesis. (de Sarre, Francois; "Initial Bipedalism: An Inquiry into Zoological Evidence," Bipedia , 1:3 , September 1988.) Comment. Obviously, de Sarre is taking an extreme position, and any observations supporting his position are anomalous by definition. From Science Frontiers #65, SEP ...
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... Glander divides howler monkey females into three groups. In the first are the high-ranking females that predominantly produce male offspring. This 'male-offspring' strategy favors these females because the males they produce tend to become dominant adults that will pass on more of the females' genes than would female offspring, who are limited in the number of infants they can engender in comparison to the males. Similar optimization strategies, according to Glander, induce middleranking females to produce mainly female progeny, and low-ranking females to birth almost all males. These howler monkeys seem to control the sex of their offspring pharmologically by selecting certain plants to eat. These plants, in turn, control the electrical conditions in the females' reproductive tracts to either attract or repel sperm carrying the male Y-chromosomes, which are thought to carry different electrical charges than the X-carrying sperm! (Lewin, Roger; "What Monkeys Chew to Choose Their Children's Sex," New Scientist, p. 15, February 22, 1992. Also: Gibbons, Ann; "Plants of the Apes," Science, 255:921, 1992.) Comments. It will take much more research to validate these startling assertions. We also have to ask how these instincts (or conscious, calculated strategies?) evolved. Since so many of the medicinal plants are distasteful, why would the monkeys eat them in the first place and thus learn, instinctively or consciously, their value in advancing the prospects for their genes? Reference. The medicinal use of plants by mammals (more ...
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... , as merely an example of variation within a species. We now quote the lead sentences from her discussions of the next two candidates: "An incipient neospecies of Drosophila may have developed in Theodosius Dobzhansky's laboratory sometime between 1958 and 1963 in a strain of D. paulistorum...." "A probable instance of a naturally emerging plant species was discovered on both sides of Highway 205 at a single locality 25.5 miles south of Burns, Harney County, Oregon...." We have inserted underlining beneath the two words that greatly weaken the paper. In short, the biologists are not really sure that speciation occurred in these two cases. The reasons for doubt are also presented. The paper concludes with a discussion of allopolyploidy in plants, in which the chromosomes of a sterile hybrid are doubled, giving rise to a fertile variety. Allopolyploidy has been observed in primroses, tobacco, cotton, and other plants. And that's it; two questionable examples and allopolyploidy. (Callaghan, Catherine A.; "Instances of Observed Speciation," American Biology Teacher , 49:34, January 1987.) From Science Frontiers #54, NOV-DEC 1987 . 1987-2000 William R. Corliss ...
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