COSMIC ANCESTRY | Quick Guide | What'sNEW - Later - Earlier - Index | by Brig Klyce | All Rights Reserved |
What'sNEW Archives, September - December 19971997, December 19: Horizontal gene transfer is looking more important than ever as a driver of evolution. Microbiologist Robert Miller of Oklahoma State University reports, "Genes travel between independent bacteria more often than once was assumed." And because such exchange can occur across the boundaries separating bacteria, eukaryotes and archaea, he concludes, "Horizontal gene exchange may thus have influenced any number of life-forms." Even without the help of viruses, "some 'promiscuous' plasmids can transfer DNA between very unrelated species... even from bacteria to yeast cells and plants." Evolutionary mechanisms such as this are required in Cosmic Ancestry.
1997, December 9: Scepticism about the tiny comets reported by a NASA scientist in May is growing. At the Fall Meeting of the American Geophysical Union, held in San Francisco, December 8-12, George K. Parks, Mitchell Brittnacher, L. Chen, R. Elsen, M. McCarthy, Glenn Germany, and James Spann presented a paper, "Does the Ultraviolet Imager on Polar Detect Cometesimals?" The debate afterwards was sometimes heated, according to reporters present.
1997, December 4: The debate over the evidence for past life on Mars continues. Three eminent meteoriticists have made their own examination of samples from ALH84001 and conclude that the shapes resembling nanofossils are probably "emergent substrate lamellae or magnetite whiskers." They say that among other problems, the gold coating used on the NASA sample can create the appearance of segmentation. McKay et al. respond that they are aware of the appearance of lamallae and they allowed for the effect of the coating, but the shapes they saw are biological. The question probably will not be resolved until samples of martian soil are returned to Earth.
1997, November 23: The integration of genes from a non retroviral RNA virus into the DNA of eukaryotic cells has been demonstrated. Three scientists from the Institute of Experimental Immunology in Zurich have shown that genes from a segmented RNA virus can become reverse-transcribed into the DNA of its host, a mouse. Retroviruses, which carry a gene for reverse transcriptase, are known to have this capability, but ordinary RNA viruses such as the one in this study carry no such gene. Opponents of cosmic ancestry had previously argued that only genes from retroviruses, not ordinary RNA viruses, could become integrated into their hosts' DNA.
1997, November 6: NASA approves comet sample return mission: DS-4 mission is a NASA program... to be launched in the year 2003.... Following a two-year journey, it will rendezvous with Comet Tempel 1 in late 2005.... After studying the comet by orbiting around it, the spacecraft will send a lander down to the surface of the comet.... Once firmly in place, the lander will use a one-meter drill to collect and analyze the make-up of the comet nucleus at various depths below the surface.... The lander will then return to the orbiter and transfer the sample to the spacecraft....The comet samples will arrive back on Earth in June 2010.
1997, October 23: The amino acids in the Murchison meteorite now weigh even more heavily in favor of life. As a letter to Nature from Stephen F. Mason of Cambridge explains, synchrotron radiation is not likely to have caused the amino acids in Murchison to accumulate excesses of the L-enantiomer. Synchrotron radiation from a neutron star had been the leading non-biological explanation for the observed excess. But after reviewing two studies done in the 1930s, Mason concludes that the mechanism would work only in highly contrived situations unlikely to occur in space.
1997, September 18: Michael H. Engel and Stephen A. Macko announce additional evidence that the excess of left-handed amino acids in the Murchison meteorite was not caused by earthly contamination. Using new techniques, they analyzed Nitrogen isotope ratios from tiny samples taken from the amino acids, not the surrounding material. The ratios establish that the amino acids are indiginous to the meteorite. Engel and Macko comment, "The origins of the excess in the L-enantiomers presently remains unclear." Life is the only process that we know can create excesses of left-handed amino acids.
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COSMIC ANCESTRY | Quick Guide | What'sNEW - Later - Earlier - Index | by Brig Klyce | All Rights Reserved |
Miller, Robert V. "Bacterial Gene Swapping in Nature" p 66-71 v 278 n 1, Scientific American. January 1998.
Viruses...
1997, December 16: NASA's Galileo spacecraft today successfully made its closest-ever flyby of Jupiter's icy moon Europa, marking the start of an extended mission that will focus on new and tantalizing scientific questions.... Galileo dipped over Europa at an altitude of only 124 miles (200 kilometers), with the signal received on Earth at 7:49 a.m. EST [16 Dec, 1997]. This was the first encounter of the Galileo Europa mission, which began formally on Dec. 8, following the end of Galileo's primary mission. The Galileo Europa mission will study Jupiter's icy satellite in detail in hopes of shedding more light on the intriguing prospect that liquid oceans may lie under Europa's ice crust. Today we begin to get the closest look ever at Europa's surface. It resembles rafted ice. Liquid water is the only invariable requirement for life to grow. Cosmic Ancestry predicts that, if Europa has a liquid ocean, as it appears, there's life in it. The exploration of Europa will be fascinating and directly relevant to Cosmic Ancestry.
Closest Europa Flyby Marks Start of Galileo Mission "Part II"
The genes can even become part of the germline
1997, November 22: Four of the NASA scientists who first announced evidence of life in a martian meteorite now say that Mars may still support life — they never said that before. The comment springs from accumulating evidence for water on Mars including a sharp 1979 Viking 2 color photo of water-frost, apparently, on the martian ground. In a Scientific American article they also give a clear and concise review of the case underlying their original conclusion, and they cite several new studies that support it. One example is an analysis suggesting that the ancient martian bacteria consumed methane.
1997, October 30: The inventor of inflationary cosmology, the leading version of the big bang theory, reinforces the idea that the universe(s) may be eternal. In The Inflationary Universe Alan H. Guth of MIT says, "...I believe that soon any cosmological theory that does not lead to the eternal reproduction of universes will be considered as unimaginable as a species of bacteria that cannot reproduce" (p 252). This process could extend backward as well as forward. Thus the argument that life must have a beginning because the universe has a beginning is shown to be questionable. The book is a readable and personal account of modern cosmological theory with lots of helpful introductory material and a Foreword by Alan Lightman.
1997, October 5: A new book by Barry DiGregorio gives a behind-the-scenes account of the Viking LR experiment and explains other evidence — especially the colors of rocks and soils — for life on Mars. Mars: The Living Planet also stresses the danger of forward- and back-contamination by interplanetary spacecraft. It contains many references, one chapter by Gilbert Levin, and one by Patricia Ann Straat.
An Interview with Barry by Laura Lee