26 results found.
... 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 Are parasites really the masters?All animals harbor parasites; and some parasites even have their own parasites. The usual effect of a parasite upon its host is debilitation, often to the point of death. But parasites have to reproduce, and some settle for the modification of their hosts in ways that improve their chances. Parasites can change the size, color, and even the behavior of their host. The object is usually to encourage a specific predator to eat the host so the parasite can continue its life cycle. A classic example is the lan-cet fluke which infests ants and then sheep. The problem is that sheep don't normally eat ants, giving the flukes a chance to switch vehicles. So, the innovative flukes somehow force the ants to crawl to the tops of plants and lock themselves there with their jaws. The next hungry sheep that comes along has his meal seasoned with ants. The bulk of the present article deals with thorny-headed worms, which are not as endearing as the lancet flukes. These parasites are merely bags of reproductive organs attached to a thorny probiscus, by which they attach themselves to the intestinal walls of vertebrates. Living in a sea of processed nutrients, the worms don't even have a digestive tract. Part of the life cycle of this parasite is spent in arthropods (insects, crustaceans). As with the lancet fluke, the thorny-headed worm ...
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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 Parasites may reprogram host's cell The long, segmented filament shown in the illustration consists 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 ...
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... Science Frontiers ONLINE No. 119: Sep-Oct 1998 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Murder In The Nest In a recent issue of BioScience, R.B . Payne authored an excellent review of brood parasitism in birds. Brood parasites lay their eggs in the nests of other species, which then incubate the eggs and raise the alien chicks. The parent parasites are thus free to forage, hang out, and parasitize more nests. Brood parasitism is such a successful and easy way of life that 136 species of cuckoos, 5 species of cowbirds, 20 finches, and South America's Blackheaded Duck have adopted it. Brood parasitism fascinates ornithologists because it involves war between the parasites and their hosts. Since host species may eject parasite eggs or fail to nurture parasite chicks, brood parasites have evolved mimicry as a powerful weapon in these battles. Mimicked are host eggs, host nestlings, and host vocalizations. But the most insidious weapons of all involve the outright murder of host chicks. To this end, parasite chicks have evolved some special weapons and behaviors. Some cuckoo chicks evict host eggs or chicks by squirming under them and positioning them in a specially configured hollow on their backs. Then, pushing upward and outward to the rim of the nest, they dump their cargo over the edge. Other brood parasites are more direct and bloodthirsty. "Nestling African honeyguides have bill hooks to stab and kill their nestmates and the brood parasitic American striped cuckoos have independently evolved hooks and pincers to kill." (Payne ...
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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 Parasites Control Snail Behavior A species of estuarine snail bearing the larvae of the trematode parasite Gynae cotyla adunca behaves radically different than it does when not infected. It lets itself become stranded high on beaches and sandbars, where it becomes easy prey to crustaceans living in this region. These crustaceans serve as the parasite's next host. Somehow, the parasite is able to modify the snail's behavior in a way that enhances its own chances for success. The question, as always in such cases, is how? And if it is a chemically induced change in behavior, how did it evolve? (Curtis, Lawrence A.; "Vertical Distribution of an Estuarine Snail Altered by a Parasite," Science, 235:1509, 1987.) Comment. Is present human behavior, thought by some to be irrational or suicidal, controlled by some unrecognized parasite that will ultimately benefit? Someone must have written a science fiction story on this theme. From Science Frontiers #52, JUL-AUG 1987 . 1987-2000 William R. Corliss ...
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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 Evolution Of Man And Malaria Malarial parasites are customarily classified according to the species infected and then further subdivided by morphology and biological characteristics. The two assumptions implicit in this classification procedure, which is supposed to mirror actual historical evolution, are: Malarial parasites evolved in parallel with their hosts; and Morphology is a measure of evolutionary relatedness. With modern biochemical techniques it is possible to test these assumptions by comparing the DNA structures of the different malarial parasites. P. falcipa rum, the parasite transmitting the most deadly human malaria, turns out to be more closely related to rodent and avian malaria than the other primate malarias. Therefore, assumption #1 above is in correct in this view. Assumption #2 is also wrong because some species of malaria parasites which are very similar morphologically are quite different DNAwise. (McCutchan, Thomas F., et al; "Evolutionary Relatedness of Plasmodium Species as Determined by the Structure of DNA," Science, 225:808, 1984.) Comment. The article does not draw attention to still another assumption; namely, that similarities are measures of evolutionary relatedness. If this as sumption isn't correct, evolutionary family trees based on bodily structure, which means most of the family trees in the textbooks, may not truly reflect what really happened in the development of life. Further, if malarial parasites did evolve along with their hosts, hu man evolution seems farther removed from the evolution ...
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... Science Frontiers ONLINE No. 61: Jan-Feb 1989 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Egg Mimicry In Cuckoos In Britain, cuckoos mainly parasitize five species of smaller birds. They do this by laying their eggs in the hosts' nests. After hatching, the young cuckoos grow much faster than the young of the host species. Soon the cuckoo is able to eject the host's young from the nest and get all the food brought by the parents. Actually, the cuckoo is so aggressive in this business of parasitization that, when it finds a host nest with eggs so far along in incubation that parasitization is impractical, it destroys the whole nest. This usually forces the host birds to lay fresh eggs, giving the cuckoo a chance to parasitize the nest. The most remarkable thing about cuckoo parasitism is the birds' ability to match the eggs of the host species in size, spottedness, background color, and darkness. The eggs of all five species commonly parasitized in Britain are much smaller than a bird the size of the cuckoo would normally lay; but the cuckoo still manages to lay eggs of just the right size. When the bona fide eggs of the five parasitized species are placed side-by-side with the mimics layed by the cuckoos, the matches are uncanny - except in the case of the dunnock, which the cuckoo doesn't try to mimic at all. The question, of course, is how the cuckoos do it. American cuckoos rarely parasitize the nests of other ...
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... communication may be more subtle than trills and squawks. Take, for example, the observation that the last egg laid by several species is distinctly lighter in color than the others in the clutch. This late-egg phenomenon is seen in the sparrows especially (House, Tree, Dead Sea, Grey-Head, and others). Common Terns, Fieldfares, Herring Gulls, and Moorhens also lay pale last eggs. Since the changes in the egg production line exact a cost in the females, there might be an adaptive explanation for the phenomenon; that is, the final paler egg may lead to increased survival of the participating species. To illustrate, in 1980, Yom-Tov suggested that: .. .this last odd egg might have evolved as a signal to potential brood parasites that the female has finished laying the clutch and has begun incubation. If a parasite lays its egg after incubation has commenced, then it would be unlikely to hatch, hence the potential parasite would benefit from heeding such a warning signal, if it could then find an alternative host nest where incubation had yet to commence. The signaling host would also benefit from avoiding the costs of warming an extra egg [the parasite's ] for some of the incubation period, costs that can be considerable, as well as the possible cost of having to rear an extra chick. G.D . Ruxton et al have used game theory to show that Yom-Tov's speculation has considerable merit. However, there are nonadaptive explanations. The females in the species that lay pale last ...
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... : Hard to Find BBB5 The Aesthetic Sense in Birds BBB6 Calculated Deception: Birds That Cry "Wolf" BBB7 Avian Play BBB8 Anomalous Aerial Tumbling and Erratic Flight BBB9 Leks: Why Did They Evolve? BBB10 Cooperative Displays on Leks BBB11 Enigmatic Dancing, Flying, Singing BBB12 Anting BBB13 "Hangers"; Upside-Down Birds BBB14 Curious Automatisms BBB15 Handedness (" Footedness") in Birds BBB16 Unusual Aerial Transportation Techniques BBB17 Unusual Forms of Terrestrial Locomotion BBB18 Unusual Hunting Strategies BBB19 Cooperative Hunting BBB20 Prey-Handling Puzzles BBB21 Avian Prey and Food: Some Misconceptions BBB22 Unusual Sexual Behavior BBB23 Avian "Sperm Wars': Cloaca Pecking BBB24 Unusual Mating Systems BBB25 Two Species with a Common Nest BBB26 Determination of Clutch Size BBB27 Exotic Objects and Eggs in Nests BBB28 Unusual Methods of Heating and Cooling Eggs BBB29 Brood Parasitism: How Did It Begin BBB30 Disparities between Parasite Host Adaptations BBB31 Tolerance of Parasite Chicks BBB32 Tolerance of Parasite Eggs Even When They Are Recognized as a Threat BBB33 Murder for Purposes Other Than Food and Brood Reduction BBB34 Infanticide BBB35 Siblicide BBB36 Information Processing in Migratory Behavior BBB37 Uncommon Groupings of Birds BBB38 Flock Synchrony BBB39 Flight Formations BBB40 Avian "Courts" and "Funerals" BBB41 Avian Graveyards BBB42 Huddling and Stacking BBB43 Bird Battles BBB44 Miscellaneous Curiosities of Avian Behavior BBC CHEMICAL PHENOMENA BBC1 Palatable Eggs More Vulnerable to Predation BBC2 Conspicuous Plumage Advertises Unpalatability BBC3 Why Did Stinking Birds Evolve? BBC4 Poisonous Birds and Poison Dart Frogs: Convergent Evolution? BBC5 Are Ratites More Primitive Than Flying Birds? BBC6 Did Australian Songbirds Evolve Earlier than European Songbirds? BBC7 Are Birds More Closely Related to Mammals Than to Reptiles? ...
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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 Fish Tales From the Mouth of Fishes Several species of fishes live inside the mouths and gills of larger species of fish. Some are true parasites. Attached by their teeth, they drink the blood of their hosts. Other fishes have fins that have been transformed into adhesive disks that allow them to also live inside the mouths and gill cavities of larger fish. These are true symbionts that feed on food scraps. The sizes and shapes of these invaders are neatly adapted to the mouths and cavities of each host. It is possible, but not easy, to explain how these remarkable physiological and behavioral transformations were initiated and perfected via random mutations and natural selection. (Gudger, E.W .; "Fishes That Live in the Mouths or Gill Cavities of Other Fishes," Scientific Monthly, 24:556, 1927.) A fish living within a fish. The shapes and sizes of such symbionts and parasites have evolved to fit their unusual niches. E.W . Gudger (see above) collected all sorts of piscine anomalies. He would have been delighted to learn of a really bizarre type of parasitism involving the spotted rose snapper (and probably other species) and a parasitic isopod (a relative of crabs and lobsters). The isopod first invades the mouth of the host fish and then consumes its tongue. It then hooks itself into the place where the tongue used to be and, being about the same ...
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... Science Frontiers ONLINE No. 135: MAY-JUN 2001 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Host Tapeworms For Health!?While K. Fujita, of Tokyo's Medical and Dental University, was studying tropical diseases in Borneo, he was amazed to discover how remarkably healthy the children were, despite the heavy loads of parasites they carried. Fujita asked himself what seems like a ridiculous question: Could some parasites actually promote good health? Ensnared by this thought, he tested the idea by introducing a tapeworm into his own gut. Both Fujita and tapeworm did well. So well, that Fujita now hosts four thriving tapeworms! Fujita wonders why his colleagues are not interested in his experiment. They don't invite him to their meetings anymore. (Anonymous; New Scientist, p. 116, New Scientist, February 24, 2001.) From Science Frontiers #135, MAY-JUN 2001 . 2001 William R. Corliss Other Sites of Interest SIS . Catastrophism, archaeoastronomy, ancient history, mythology and astronomy. Lobster . The journal of intelligence and political conspiracy (CIA, FBI, JFK, MI5, NSA, etc) Homeworking.com . Free resource for people thinking about working at home. ABC dating and personals . For people looking for relationships. Place your ad free. ...
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... Science Frontiers ONLINE No. 86: Mar-Apr 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects How A Fly Hears What A Cricket Hears As we all know, male crickets chirp long and loud for mates from spring until fall. That many males are successful in attracting females is obvious from this insect's population levels. Some of the singing males, however, attract parasitic flies that home in on their songs and deposit their maggots on or near them. Within 10 days, these singers are silent -- they have been consumed by the maggots. The really interesting part of this tale involves the hearing organs of the crickets and flies. Normally, they are radically different in design and frequency of operation. Crickets usually sing at frequencies above 3 kilohertz, and their ears are attuned to these high frequencies. The usual fly, on the other hand, hums and buzzes at only 100-500 hertz (cycles per second). Their ears are duly optimized at these frequencies. The cricket-hunting flies (genus Ormia ), however, would starve to death if they couldn't hear the highpitched cricket songs. Their response was to "evolve" a cricket-type ear so they could home in on their prey. This is a remarkable example of evolutionary convergence. (Robert, Daniel, et al; "The Evolutionary Convergence of Hearing in a Parasitoid Fly and Its Cricket Host," Science, 258:1135, 1992.) Comment. How did the parasitic flies survive until they evolved ...
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... Science Frontiers ONLINE No. 1: September 1977 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Australian Mistletoes Mimic Their Hosts Many species of Australian mistletoes closely mimic their hosts in leaf form and general appearance, blending deceptively into the host's foliage. Plant mimicry for purposes of protection (for example, stone plants) and for propagation are well known and, in the logic of evolutionists, have evolved because of the advantages conferred on the species. Since the Australian mistletoes are evidently highly palatable to arboreal marsupials, the tenets of evolution hold that it is only natural that these mistletoes should develop so as to resemble their hosts for purposes of protection. This is called cryptic or camouflage mimicry. Australian mistletoes parasitize a wide variety of plants, and it is truly marvelous how they can detect and imitate the leaves and appearances of such a wide variety of hosts. (Barlow, Bryan, and Wiens, Deibert; "Host Parasite Resemblance in Australian Mistletoes," Evolution, 31:69, 1977.) From Science Frontiers #1 , September 1977 . 1977-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 37: Jan-Feb 1985 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology A Disaster-driven Early Civilization Another Remarkable Specimen of Ancient Man Astronomy The Puzzle of the Moon's Origin When Mars Had Lakes Why Aren't the Martian Craters Worn Down? Flip-flop Radio Jets? Biology The Genome's Responses to Challenges "hopeful Monsters" in Iceland? Parasites May Reprogram Host's Cell Geology More Doubts About Asteroids The Earth is Expanding and We Don't Know Why The Grand Canyon Conundrum Evidence for A Giant Pleistocene Sea Wave Recent Pulsations of Life Geophysics "Crystal" Ball Lightning The Big Divot! Shower of Coke Chemistry & Physics Squarks and Photinos At Cern? What Does it All Mean? The Secret of it All is in the Pi ...
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... Science Frontiers ONLINE No. 126: Nov-Dec 1999 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Swimming Up The Wrong Streams Of course, most freshwater fish do swim upstream in the usual way, but not the candiru. It is partial to very specific streams. This small, slim, scaleless species of catfish inhabits the Amazon where it preys on other fish, often by invading their gills and feasting on blood and tissue. They also aim much higher on evolution's ladder: they are the only known vertebrate parasites of humans. It is when they prey upon humans that they swim up the wrong streams -- at least their victims think so! Their technique is simple. They detect human urine released by swimmers and follow it right to the source. They don't stop there but insert themselves right into the penis and keep going, sometimes all the way to the bladder. Once inside the penis they erect their spines and cannot be extracted except by surgery. Left alone, they are not only excruciating to the unwise bather but can eventually be fatal. Surgeons have successfully extracted them from the bladder, but in remote areas penis amputation is the only answer! (Warren, Nicholas; "In Mare Internum," Fortean Times, p. 14, September 1999. Title translation: "Within the Inner Sea.") From Science Frontiers #126, NOV-DEC 1999 . 1999-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 26: Mar-Apr 1983 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Nature's ballistic missile Abstract: "The parasitic fungus Haptoglossa mirabilis infects the rotifer host by means of a gun-shaped attack cell. The anterior end of the cell is elongated to form a barrel; the wall at the mouth is invaginated deep into the cell to form a bore. A walled chamber at the base of the bore houses a complex, missile-like attack apparatus. The projectile is fired from the gun cell at high speed to accomplish initial penetration of the host." (Robb, E. Jane, and Barron, G.L .; "Nature's Ballistic Missile," Science, 218:1221, 1982.) From Science Frontiers #26, MAR-APR 1983 . 1983-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 34: Jul-Aug 1984 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Ancient Wisconsin Astronomers The Guadeloupe Skeleton Revisited Pouring A Pyramid A Demurrer From the Epigraphic Society Ancient Old-world Lamps Turn Up in New England Astronomy Does String Hold the Universe Together? The Big Bang As An Illusion A Gathering of Quasars Biology Our Aquatic Phase! Dna even more promiscuous A Note on Perfect Pitch Sunspots and Disease Are Parasites Really the Masters? Geology The Carbon Problem Behind Magnetic Flip-flops Geophysics Aggressive Ball Lightning Low-level Aurora? The Marfa Lights Psychology The Mind's Control of Bodily Processes Hostage Hallucinations Techno-jinx Unclassified Strange Object in the Sky ...
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... Science Frontiers ONLINE No. 148: Jul-Aug 2003 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Who or What Exterminates the Pleistocene Megafauna? Illinois's Ancient Maginot Line A Cold Barrier to Internal Parasites Astronomy Are there no other Earths out there? Where's the Fuzz? Biology Snakes Aloft Woman's Barr Bodies The Eyes have it A Major Problem for Darwinism Geology Why are old Mountains High? Subterranean Ecosystems Geophysics Milky-sea Phenomenon Is the Min Min Light a Fata Morgana (mirage)? Pre-Quake Anomalies Psychology Correlations of Brain Activity Physics A Revolution in Electrostatics Mathematics Ordering a Piece of Pi Prime Squares ...
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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. 81: May-Jun 1992 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Plants Of The Apes Many biologists are convinced that apes, bears, cats, and dogs eat plants -- many of them obviously distasteful -- in order to medicate themselves for diseases and parasites. What also seems likely, according to K. Strier, of the University of Wisconsin, Madison, is that some monkeys regulate their fertility by the judicious consumption of certain plants. Going even farther, K. Glander, Duke University, suggests that howler monkeys control the sex of their offspring through their diets. 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 ...
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... Jeff; "Neanderthal DNA Has Little Human Link," Austin American-Statesman, March 29, 2000. Cr. D. Phelps.) Comment. From among many possible comments, we settle for just one: It is relevant that mtDNA is not the nDNA (nuclear DNA) that is the primary determinant of an animal's morphology and other attributes. Scientific consensus now holds that mtDNA comes from bacteria that invaded complex cells (eukaryotes) and set up housekeeping in them eons ago. The mitochondria are called "endosymbionts," but we must wonder how symbiotic they really are. Not only does mtDNA mutate much faster than nDNA (" our" DNA), but the mitochondria the mtDNA serves must have different evolutionary goals from us; that is, mitochondria might really be parasites and we are their hosts! See next item. From Science Frontiers #130, JUL-AUG 2000 . 2000 William R. Corliss Other Sites of Interest SIS . Catastrophism, archaeoastronomy, ancient history, mythology and astronomy. Lobster . The journal of intelligence and political conspiracy (CIA, FBI, JFK, MI5, NSA, 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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... disorders. The first item (or "force") is the most disturbing. Mitochondria (with only 35 genes), it seems, can exercise vetoes over decisions by our own genome (with its 100,000 genes). (Cohen, Philip; "The Force," New Scientist, p. 30, February 26, 2000.) The cells of higher organisms are busy places. One of this cell's mitochondria is indicated at the lower right, but there are several others in the sketch. They have their own DNA (mtDNA). Comment. It is disconcerting to realize that within each of our cells hundreds of alien entities, though helpfully supplying energy, are mutating and evolving in ways to enhance their fitness rather than ours. Like so many true parasites, mitochondria will not shrink from modifying their hosts (us!) to achieve their ends -- whatever they are. The Force seems to be with them! From Science Frontiers #130, JUL-AUG 2000 . 2000 William R. Corliss Other Sites of Interest SIS . Catastrophism, archaeoastronomy, ancient history, mythology and astronomy. Lobster . The journal of intelligence and political conspiracy (CIA, FBI, JFK, MI5, NSA, 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. 82: Jul-Aug 1992 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects For some, sex = death It has long been known that the males of some species of marsupial mice mate in their first year and then die off completely, leaving the perpetuation of their species to their male progeny. Females of these species usually survive to breed a second and even third year. The poor males, however, succumb due to "elevated levels of free corticosteroids in the blood and associated disease such as hemorrhagic ulceration of the gastric mucosa, anemia, and parasite infestation." In short, they seem programmed to die after mating, like the male octopus. And one wonders why evolution has wrought this mass die-off. In their studies of marsupial mice, C.R . Dickman and R.W . Braithwaite have extended the phenomenon to two new genera: Dasyurus and Parantechinus . They have also found that the phenomenon is a bit more complex. First, in P . apicalis, the male die-off occurs in some populations and not others. In D. hallucatus , the die-off may occur in the same population in some years and not others. Furthermore, the females of this species may on occasion all die off, too -- but after giving birth, of course. (Dickman, C.R ., and Braithwaite, R.W .; "Postmating Mortality of Males in the Dasyurid Marsupials, Dasyurus and Parantechinus ," Journal of Mammalogy , 73: ...
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... Science Frontiers ONLINE No. 85: Jan-Feb 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The Lures Of Mussels Mussels entrust their larvae to the vagaries of the waters in which they live. How, then, are mussels ever able to colonize rivers, whose currents would always sweep their larvae downstream? A pseudofish with tail, fins, and eye spot displayed by a mussel. "The riverine pioneers ran this roadblock by custom designing their baby mussels to hitchhike on fish. Kneehigh to a pinhead, the larval mussel, or glochidium, is nurtured by the thousands or millions in their mother's gills, and spewed in teeming puffs to the open waters. They cling as benign parasites to passing fish, and take a one- to three-week trip, drawing nutrients through their host's membranes and a free ride to new dwellings. They then drop to the bottom and begin their independent lives, some of which will span a half century or more. "Glochidia that do not hook up with a host fish are doomed. To cover these stakes, the pocketbook mussel and its relatives have evolved a fleshy appendage that flaps in the currents and, to a smallmouth bass, looks like a breakfast minnow. Taking the bait. the duped fish gets doused with glochidia. Another resourceful mussel sends its glochidia out in pulsating little packets resembling worms." (Stolzenburg, William; "The Mussels' Message," Nature Conservancy , p. 17, November/December 1992.) From Science Frontiers ...
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... 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 The Mite Pockets Of Lizards "Many lizards are infested by chig gers, the larvae of trombiculid mites, which feed on tissue fluid and cell debris. Surprisingly, lizards seem to go out of their way to attract the chiggers -- they have special mite pockets that provide a protected, warm and humid site. In many cases, the skin of the lizard also has smaller scales than normal and a good blood supply in the pocket, which enables the parasites to feed more readily." There does not seem to be any advantage to the lizards providing plush accommodations for the chiggers. The chiggers can wreak havoc on their hosts in the form of skin lesions, allergic reactions, secondary infections, and the transmission of diseases. Nevertheless, some 150 species in 5 distinct lizard families possess mite pockets, which are often located in different places in different lizard species. Apparently, the mite pockets evolved separately several times. But why? (Benton, Michael J.; "The Mite Pockets of Lizards," Nature, 325:391, 1987.) Comment. Why haven't the lizards evolved thicker skin or some sort of chemical defense instead of reducing their fitness with mite pockets? Or, are other factors operating? From Science Frontiers #51, MAY-JUN 1987 . 1987-2000 William R. Corliss ...
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... Science Frontiers ONLINE No. 52: Jul-Aug 1987 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Costa rica's neglected stone spheres The calico debate, plus a little editorializing Astronomy Small icy comets and cosmic gaia Carbon in a new comet Meteorites also transport organic payloads Supernova confusion and mysteries "COMPACT STRUCTURES": WHAT NEXT? Biology Nose news Checklist of apparently unknown animals New vertebrate depth record Aggressive mimicry Parasites control snail behavior Geology Do large meteors/comets come in cycles? Complexities of the inner earth Geophysics Concentrated source of lightning in cloud More carolina waterguns More moodus sounds Inside a texas tornado Ship enveloped by false radar echo Psychology Dowsing skeptics converted Do dreams reflect a biological state? ...
Terms matched: 1 - Score: 13 - 15 May 2017 - URL: /sf052/index.htm
... , 3 indexes, 1996. 527 references, LC 91-68541. ISBN 0-915554-31-3 . 7" x 10". Biological Anomalies: Birds: A Catalog of Enigmas and Curiosities Sorry, Out of print Birds are everywhere: some can fly high over the Himalayas, others can dive as deep as 500 meters in the oceans, some migrate unerringly from one end of the earth to the other. With more than 9,000 species recongnized, birds present us with hundreds of scientific puzzle to solve. Typical subjects covered: Asymmetric birds * Wing claw and spurs * Inherited callosities * Unrelated birds that look alike * Enigmas of avian instincts * The intelligence of birds * An avian aesthetic sense? * Birds that roost upside down * The insiduous nature of brood parasitism * Avian battles, courts, funerals * Unsolved mysteries of migration * Poisonous birds * The unique avian respiratory system * The two-voice pheonomenon * Echolocation in birds View Cart Buy online via PayPal with MC/Visa/Amex 486 pages, hardcover, $27.50, 150 illus., 3 index, 1998. 1170 references, LC 91-68541. ISBN 0-915554-32-1 , 7" x 10" Incredible Life: A Handbook of Biological Mysteries Out of print Hardcover, 1018 pages, March 1981, ISBN: 0-915554-07-0 , 9.5 x 6.5 x 0.2 inches Unfathomed Mind: A Handbook of Unusual Mental Phenomena Out of print Hardcover, 754 pages, Apr 1982, ISBN: 0- ...
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