mirrored file at http://SaturnianCosmology.Org/ For complete access to all the files of this collection see http://SaturnianCosmology.org/search.php ========================================================== *ONLINE* *No. 85: Jan-Feb 1993* *Issue Contents * ------------------------------------------------------------------------ Other pages ------------------------------------------------------------------------ ** * *Home Page <../index.htm>* * *Science Frontiers Online * o * All Issues <../sfonline.htm> o This Issue * * *Sourcebook Project <../sourcebk.htm>* * *Sourcebook Subjects <../catalog.htm> * Click for Catastrophism.com [Site Meter] Biology's big bang Representatives of three body plans /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 back 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 "force" -- existed then but is with us no longer. (Levinton, Jeffrey S.; "The Big Bang of Animal Evolution," /Scientific American/, 267:84, November 1992.) *Comment*. If evolution is truly the result of random mutation modulated by natural selection, perhaps mutation was "different-from-random" during the Cambrian! Now that's a heretical thought. *From Science Frontiers #85, JAN-FEB 1993 . © 1993-2000 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. [Site Meter]