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... more radical notion of the entire outer layer of crust slipping over the earth's mantle like a greased onion skin. Nor is the proposed process anything like poleflipping, where the entire planet flips 180 like a Tippy-Top -- a dynamically impossible event. (SF#6 /224) The proposed foundering of that chunk of seafloor occurred 534 million years ago, roughly coincident with the Cambrian Explosion of new life forms (new phyla). The resulting gross climate changes and environmental havoc could have been conducive to the rapid evolution of life. Although today's scientists favor this linkage of catastrophism to rapid speciation, Berkeley paleontologist J. Valentine admitted that, ". .. it doesn't provide a specific mechanism by which animals suddenly evolved new "body plans." ... so, scientists have long searched for an event -- any -- that might explain the puzzling Cambrian Explosion. (Kirschvink, Joseph L., et al; "Evidence for a Large-Scale Reorganization of Early Cambrian Continental Masses by Inertial Interchange True Polar Wander," Science, 277:541, 1997. Also: Sawyer, Kathy; "Global Shift May Have Sped Evolution," Washington Post, July 25, 1997.) Comment. O.K ., but those much more recent frozen mammoths are still hard to explain. If a chunk of seafloor can founder once, the same thing might have happened twice -- say, just a few thousand years ago. But why should large chunks of seafloor sink so suddenly? Neither reference touches on this! K ...
Terms matched: 2 - Score: 300 - 15 May 2017 - URL: /sf113/sf113p07.htm
... Science Frontiers ONLINE No. 109: Jan-Feb 1997 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Biology Heavy Paleontology vs. DNA. The so-called Cambrian Explosion has been the subject of two SF items (SF#60/187 and SF#85/ 187). A paleontological fact of life is that all known body plans (phyla) seem to have evolved suddenly -- within a few million years -- after the onset of the Cambrian period some 545 million years ago. Evolutionists are understandably uncomfortable with such a high rate of evolutionary innovation. Nothing like the Cambrian Explosion appears in the hundreds of millions of years of geological strata that followed. So rapid was speciation during the Cambrian Explosion that doubt is cast upon ... accepted mechanisms of evolution: slow, stepwise accumulation of mutations plus natural selection. (Refs. 1 and 2) But G.A . Wray and colleagues seem to have rescued Darwinism. They have analyzed the DNA sequences of seven genes found in living animals. Assuming that these genes mutate at constant rates and working backwards in time, they calculate that animal diversification (i .e ., when chordates diverged from invertebrates) actually began about 1 billion years ago, rather than about 545 million years ago. This expansion of the time frame gives accepted evolutionary processes much more time to innovate and create all those new body plans. The evolutionists are pleased. The paleontologists, however, are in a quandry. They see nothing -- or very little -- in the Precambrian fossil record ...
Terms matched: 2 - Score: 280 - 15 May 2017 - URL: /sf109/sf109p08.htm
... 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 Biology's big bang Representatives of three body plans (phyla): jellyfish (coelenterata); aphid (arthropoda); eohippis (chordata); The title refers to the so-called "Cambrian explosion," that period that began some 570 million years ago, during which all known animal phyla that readily fossilize seem to have originated. The biological phyla are defined by characteristic body plans. Humans, for example, are among the Chordata . Some other phyla are the Arthropoda (insects, crustaceans), the Mollusca (clams, squids), the Nemotada (roundworms), etc. All of these phyla trace their ancestries ... to that biologically innovative period termed the Cambrian explosion. Even at the taxonomic level just below the phylum, the class (i .e ., the vertebrates), most biological invention seems to stem from the Cambrian. J.S . Levinton, in a long article in the November 1992 Scientific American, explores the enigma of the Cambrian explosion. Did some unknown evolutionary stimuli prevail 570 million years ago that made the Cambrian different from all periods that followed? Or, has something damped evolutionary creativity since then? Levinton holds that biological innovation has continued unabated at the species level since the Cambrian explosion, but that new body plans; that is, new phyla; have not evolved for hundreds of millions of years. Therefore, something special and very mysterious -- some highly creative " ...
Terms matched: 2 - Score: 256 - 15 May 2017 - URL: /sf085/sf085b05.htm
... Science Frontiers ONLINE No. 33: May-Jun 1984 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The failure of two-dimensional life The fossil record tells us that just prior to the Cambrian explosion of life, the earth was populated by a diverse assemblage of soft-bodied, shallow-water marine invertebrates, some with dimensions as large as 1 meter. This whole group of animals did not survive into Cambrian times, thus ending what has been termed The Ediacaran Experiment. Some paleontologists have tried to find similarities between the Ediacaran and Cambrian life forms to preserve the continuity of life. This has proved difficult, and some scientists now feel that The Edicaran approach to "largeness" was to increase surface area externally. The Ediacarans were ... shaped like pancakes, tapes, fans, etc. This enabled them to present large areas to the environment for respiration, feeding, and other biological functions. In contrast, many present life forms achieve "largeness" by increasing internal areas, as in the lungs, folded intestines, etc., along with the forced circulation of air, blood, and other sub stances. This latter approach survived, while the two-dimensional Ediacaran Experiment did not. The demise or extintcion of the Ediacarans led Gould, the author of this far-ranging article, to the influence of extinctions on life in general -- a hot topic these days. Gould stated that with natural selection operating, one would expect continual "improvement" in life forms, but that this had not happened. " ...
Terms matched: 2 - Score: 247 - 15 May 2017 - URL: /sf033/sf033p08.htm
... -sided evolution We risk supersaturating our readers with the anomalies of evolution, but we simply cannot bypass an article that is introduced as follows: "An analysis of the fossil record reveals some unexpected patterns in the origin of major evolutionary innovations, patterns that presumably reflect the operation of different mechanisms." The most interesting "unexpected pattern" is the gross asymmetry between the diversification of life in the Cambrian explosion (about 440 million years ago) and that following the great endPermian extinction (a little over 200 million years ago). Biological innovation was intense in both instances; both biological explosions burst upon a life-impoverished planet. Many niches were unoccupied. Even so, all existing (and many extinct) phyla arose during the Cambrian explosion and none followed the Permian extinction. ". ... .why has this burst of evolutionary invention never again been equaled? Why, in subsequent periods of great evolutionary activity when countless species, genera, and families arose, have there been no new animal body plans produced, no new phyla?" Some evolutionists blame the asymmetry on the different "adaptive space" available in the two periods. "Adaptive space" was almost empty at the beginning of the Cambrian because multicellular organisms had only begun to evolve; whereas after the Permian extinction the surviving species still represented a diverse group with many adaptations. (Just how the amount of "adaptive space" available was communicated to the "mechanism" doing the innovation is not addressed.) Scientists contemplating these matters, however, seem to concur that microevolution, which supposedly gives rise to new species ...
Terms matched: 2 - Score: 217 - 15 May 2017 - URL: /sf060/sf060p08.htm
... Science Frontiers ONLINE No. 90: Nov-Dec 1993 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The shorter, the stranger Just a few months ago (in SF#85), we held forth on biology's Big Bang: that Cambrian paroxysm of biological creativity about 570 million years ago. Until now, biologists had opined that this "explosion" required a rather leisurely 20-40 million years (still very short in geological terms). After all, biological creativity must take time if it is powered only by stepwise random mutations. But the recent dating of Cambrian formations in northeastern Siberia (which was previously off limits to Western scientists because of its Soviet radar installations) has now compressed this great event to a veritable ... . S.A . Bowring et al, in their startling report in Science, have measured the length of this period of unparalleled biological diversification at only 5-10 million years, possibly as short as a mere 1 million years! What wand of biological creativity was waved at this magical moment? It had to be something that has not happened again down the long eons that followed, for never again has nature favored our planet in this way. Never again were any more of life's major body plans (the phyla) synthesized. Even ardent evolutionists marvel at the newly measured intensity of this moment. For example, S.J . Gould has remarked: "You've taken the most accelerated period of evolutionary rates and made it a whole lot shorter. The degree ...
Terms matched: 2 - Score: 208 - 15 May 2017 - URL: /sf090/sf090b05.htm
... Science Frontiers ONLINE No. 43: Jan-Feb 1986 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Treasures In A Toxonomic Wastebasket The Burgess Shale, in British Columbia, ia all that is left of a Middle Cambrian mudbank that adjoined a massive algal reef. Here, many "experimental" forms of life prospered and succumbed. The Burgess Shale is probably the world's greatest depository of fossils of softbodied creatures. Quoting Stephen Jay Gould: "The Burgess (fortunately for us) occupies a crucial time in life's history. It represents our only 'window' upon the first great radiation of complex life on earth. All but one or two modern phyla originated in a burst of evolutionary activity associated with the so-called ... explosion some 570 million years ago. The Burgess provides our only peek at the soft-bodied forms of this first flowering. All other soft-bodied fossil assemblages are much younger; they represent faunas well past the initial burst and sorting out of Cambrian times." The morphological diversity of the Burgess Shale, incorporating many bizarre forms of life, represents a true biological revolution. Here are found a dozen genera that do not fit into any modern phylum. Most of the novelties never survived into modern times. (Gould, Stephen Jay; "Treasures in a Taxonomic Wastebasket," Natural History, 94:24, December 1985.) Comment. Somewhere on today's earth, there must be mudbanks washed by nutrient-rich waters and bathed in tropical sunlight. Is some ingredient ...
Terms matched: 2 - Score: 186 - 15 May 2017 - URL: /sf043/sf043p11.htm
... the fundamental properties of time, matter, and space -- something like a cosmic phase change (See SF#74/329.*) Apparently, something was basically different in the universe 1.9 -3 .0 billion years ago when quasars reigned. Curiously, there seems to have been something fundamentally different here on earth about 570 million years ago -- the time of the Cambrian explosion, when essentially all the basic body plans (the phyla) of life originated. (SF#85/187) If the universe is much younger than 15 billion years, as some astronomers insist, we might be able to correlate the two epochs when things were really different! *SF#85/187 = Science Frontiers #85 and p. 187 in Science Frontiers ( ... book). To order the latter, see: here . From Science Frontiers #102 Nov-Dec 1995 . 1995-2000 William R. Corliss ...
Terms matched: 2 - Score: 172 - 15 May 2017 - URL: /sf102/sf102a04.htm
... there that were never ignited and that we cannot see through our telescopes. (Herndon, J. Marvin; "Examining the Overlooked Implications of Natural Nuclear Reactors," Eos, 79:451, 1998.) Comments. Two additions to Herndon's list. Evolution of terrestrial life . Nuclear reactors produce copious mutagenic radiation. They could have accelerated the evolution of life, especially during the Cambrian Explosion. (See SF#32) Thermal plumes . Deep-seated natural nuclear reactors may create the thermal plumes said to be responsible for such surface hot spots as Iceland and Hawaii. Disposition of six of the Oklo 2-billion-year-old natural nuclear reactors. (From: Anomalies in Geology). From Science Frontiers #121, JAN-FEB 1999 . 1999- ... William R. Corliss ...
Terms matched: 2 - Score: 166 - 15 May 2017 - URL: /sf121/sf121p02.htm
