11 results found.
... Science Frontiers ONLINE No. 54: Nov-Dec 1987 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Instances Of Observed Speciation Creationists have long maintained that no one has ever observed the creation of a new species in nature. C.A . Callag han has sought to counter this attack on evolution with a paper bearing the above title. Her concluding paragraph is: "I have cited several instances of ob served speciation that can be used as illustrative examples in the classroom. They should also silence at least one common creationist argument against evolution." The paper begins with the well-worn peppered-moth story; but Callaghan quickly dismisses this, as the creationists do, 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 ...
Terms matched: 1 - Score: 99 - 15 May 2017 - URL: /sf054/sf054b06.htm
... 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 Recent Pulsations Of Life At a recent meeting of scientists at the Lamont-Doherty Geological Observatory, E. Vrba, of the Transvaal Museum, in Pretoria, stated: "If we eventually are able to establish a good time resolution with the continental record, I expect to be able to discern synchronous pulses of evolution that involve many groups of fauna and flora. Many different lineages in the biota will respond by synchronous waves of speciation and extinction to global temperature extremes and attendant environmental changes. This is my starting hypothesis." Vrba was speaking mainly about the last 25 million years, a mere flash in geological time. For this brief period, the Deep Sea Drilling Program has provided geologists with a detailed and continuous record of climate changes as they were recorded in deep-sea sediments. By contrast, the faunal history of the continents is rather fragmentary, making it rather difficult to match up pulsations of climate with pulsations of life. Even so, scientists have found rather strong correlations between climatary change and biological speciation and extinction at 15, 5, and 2.4 million years ago. (Lewin, Roger; "The Paleoclimatic Magic Numbers Game," Science, 226:154, 1984.) Comment. Note that this is just the period our ancestors seemed to be evolving rapidly. Also interesting is the general agreement between Vrba's statement about the driving forces behind evolution and McClintock's conclusion quoted earlier ...
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... -- an exceptionally dry period in Africa. Today, the Lake is again high and once more host to isolated rocky islands, each with its own unique complement of cichlid fish; each island has species found nowhere else in the lake. Where did all these species come from, considering that their little islands were bone dry just a century ago? Goldschmidt writes: "Cichlids that inhabited these exposed rocks would have suffocated, unless they had already left for wetter climes. Yet today, species that do not exist anywhere else can be found near almost every rocky island. From an orthodox point of view, the most plausible explanation for this is quite surprising: many color forms as well as biological species developed over a period of less than two hundred years." This is certainly explosive speciation -- real biological punctuation! But, perhaps as water levels fell, the original cichlids found refuges in surviving pools and then repopulated the lake when the waters rose. But is it reasonable to believe that they all sorted themselves out so perfectly that many species are found nowhere else in the lake? The probability seems high that cichlid speciation has been very rapid -- too rapid, one would think for random mutation and the slow feedback of natural selection to accomplish this daunting task in just a century or two. Might there not be some additional nonsupernatural factor at work? (Goldschmidt, Tijs; Darwin's Dreampond , Cambridge, 1996, p. 125.) From Science Frontiers #110, MAR-APR 1997 . 1997-2000 William R. Corliss ...
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... Project Sourcebook Subjects Did darwin get it all right?Believe it or not, the above title appeared in Science rather than the Creation Research Society Quarterly. (We never thought we'd see the day!) And right beneath, in large type, is: "The most thorough study yet of species formation in the fossil record confirms that new species appear with a most un-Darwinian abruptness after long periods of stability." In the article that follows, R.A . Kerr reviews several recent studies of fossil bryozoans and snails. Some of these painstaking dissections of the fossil record were carried out by scientists initially committed to Darwinian gradualism. Even these researchers have been forced to acknowledge that much biological evolution proceeds not in minute steps but by large jumps or saltations. Such abrupt speciation is tough enough to explain, but even more daunting are those species untouched by change over millions, even hundreds of millions of years. Indeed, the major characteristic of the fossil record and, therefore, earth life as a whole, has been stasis rather than speciation, despite all manner of asteroid impacts and climatic traumas. Nevertheless, many biologists think that species are somehow frozen in time by environmental forces that keep them from straying from their little niches. This being so, paleontologist D. Jablonski, University of Chicago, asks: If stability is the rule, how do you get large-scale shifts in morphology? How do you get from funny little Mesozoic mammals to horses and whales? From Archaeopteryx to hummingbirds? (Kerr, Richard A.; "Did Darwin Get ...
Terms matched: 1 - Score: 24 - 15 May 2017 - URL: /sf099/sf099b07.htm
... Science Frontiers ONLINE No. 50: Mar-Apr 1987 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects The fossil record and the quantization of life!A recent article on the possible quantization of galaxies was placed immediately before an interview with S. Stanley, one of the proponents of punctuated evolution. Either fate or the mysterious forces of seriality seemed to be saying that it is now time to broach the subject of the quantization of life itself. The reader can blame Stanley only for the stimulus and his discussions of speciation and the discontinuous (quantized?) fossil record. (Campbell, Neil A.; "Resetting the Evolutionary Timetable," BioScience, 36:722, 1986.) Comments. When we suggest quantization in biology, two phenomena come to the fore: 1. The obvious splitting of life into well-defined states -- the species -- as defined morphologically and/or by the genetic code; and 2. The gaps in the fossil record, which imply a frequent lack of transitional forms from one species to another. As Stanley asserts repeatedly in his interview, the fossil record is actually quite good in many places, despite the long-voiced claims of the gradualists that transitional forms do not exist merely because of the deplorable state of the fossil record. In physics the analogous phenomena would be: (1 ) The chemical elements and their isotopes (or an atom's energy levels); and (2 ) The lack of transitional forms. Straining the analogy still further, the evolution ...
Terms matched: 1 - Score: 14 - 15 May 2017 - URL: /sf050/sf050p08.htm
... Science Frontiers ONLINE No. 54: Nov-Dec 1987 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology 300,000-YEAR-OLD SITE IN BRAZIL Egyptian pyramids actually made of synthetic stone? Astronomy Icebergs and crouching giants Big-bang bashers Fractals, fractals everywhere Biology Instances of observed speciation Plants are not color blind! Electric-power plants! Honest, this is the last "plant" item! The insects' revenge Geology Now, it's comet showers that did it The changing magnetic climate: does it affect civilizations? Huge underground electrical circuit What heats the earth Geophysics Toads fall to squashy fate Ball lightning in bavaria Psychology A HOAX ADMITTED Esp of atoms? Chemistry and physics Through a peephole tantalizingly Unclassified The uncertainty of knowledge ...
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... see map). "Molchanov's controversial evidence is indeed striking: a collection of chipped and flaked rocks that are clearly artifacts fashioned by humanlike hands and that he contends are 2.5 million years old -- plus or minus a half-million years. "Remarkably, that same era marked the time when early human ancestors known as Homo habilis lived and left their remains in the tropical Olduvai Gorge of what is now Tanzania. Mochanov's collection of tools closely resembles the ones that anthropologists have long collected from digs in Africa." All this contrasts strongly with the dominant view of hominid evolution, which cites warm, verdant African forests and savannas as our most likely place of origin. Siberia, with its -50 winters and fleeting summers, hardly seems conducive to hominid speciation. Mochanov's rationale is that this severe climate actually stimulated ancient hominids to create tools, fashion warm clothing, and build winter shelters -- these Siberian hominids had to evolve or perish! In addition to the climate factor are two other problems: (1 ) The Siberian sites have yielded no hominid bones nor have animal bones of any kind been found; and (2 ) The dating of the tools is shaky. They cannot be radiometrically dated. Instead, Mochanov has had to rely on the tools' similarity to African tools of 2 million years ago, magnetostratigraphy, the decayed luminescence of the soil, and the ages of the strata in the 450-foot gorge of the Lena River. It goes without saying that other anthropologists are reserving judgment. Nevertheless, Mochanov' ...
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... 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 the 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 ...
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... Science Frontiers ONLINE No. 44: Mar-Apr 1986 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Squirrels As Measures Of Geological Time Over a century ago, when the truth of biological evolution via natural selection was hotly debated, the proponents of Darwinism were delighted when the geologists presented them with almost endless periods of time in which evolution could progress in small steps from species to species. Now, in a strange turn-about, a creationist writer is using evolutionary theory to infer a very short history for the formation where geologists want a good deal of time. We quote from the conclusion of J.R . Meyer: "If any group of animals were ever going to undergo significant degrees of evolution from parent stock and obtain resultant speciation, surely the Kaibab squirrel would be one of the more likely candidates. Supposedly isolated from their neighbors for hundreds of thousands of generations over a period of at least several million years, and significantly violating virtually every restriction of the Hardy-Weinberg equilibrium for the non-evolving population, these organisms, even by creationist standards, should have undergone significant and detectable changes. In reality all they show are moderate changes, primarily in two coat color characteristics for part of their population. To make things even worse, this species is known to have a highly variable coat-color polymorphism throughout its range. Thus, even the differences displayed appear to be easily accounted for by several mutations and a slight change in gene frequency for one or two loci, all occurring in a limited period of ...
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... 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 missing, or perhaps present, in today's mudbands that suppresses the wild speciation seen in the Burgess Shale? Tow of the many mysterous fossils found in Burgess shale. At the right is Opabina regalis, with five eyes at the base of a nose-like structure ending in teeth. On the left is Amiskwia sagittoformis. Although these creatures are named, nobody really knows what they are! From Science Frontiers #43, JAN-FEB 1986 . 1986-2000 William R. Corliss ...
Terms matched: 1 - Score: 13 - 15 May 2017 - URL: /sf043/sf043p11.htm
... Kirschvink et al used the methods of paleomagnetism. The "new" crustal slippage is really only accelerated continental drift (a dominant and well-established paradigm) and not the 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." Even 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 ...
Terms matched: 1 - Score: 13 - 15 May 2017 - URL: /sf113/sf113p07.htm