What'sNEW Archives, October - November 1999
November 29: Tunguska explosion probably caused by a comet — Kaare Lund Rasmussen's team at the National Museum and Geological Survey of Denmark in Copenhagen analysed carbon isotope ratios and iridium abundances to conclude that the object that exploded over the Tunguska forest, in 1908, was a block of ice from a comet. They even think they can identify the comet.
Comet Chunk Marred Siberian Forest, by Michael de Laine, Discovery News Brief, 29 November 1999.
Exploring century's greatest explosion, by David Whitehouse, BBC News Online, 26 July 1999.
Comets: The Delivery System is a related Cosmic Ancestry webpage.
November 22: Genetic and Evolutionary Computation Conference (GECCO-2000) will be held July 8-12, 2000 in Las Vegas, NV. It is a combination of the Annual Genetic Programming Conference and the International Conference on Genetic Algorithms with Darrell Whitley of Colorado State University as General Chair.
Genetic and Evolutionary Computation Conference (GECCO-2000).
...Is Evolutionary Progress ...Possible? is a related CA webpage.
November 18: NASA's Center for Computational Astrobiology was inaugurated today at Ames Research Center, Moffett Field, CA, during a symposium entitled "Computational Astrobiology for the 21st Century." Among the experts who spoke were Dr. Andrew Pohorille, who will head up the new center, and two Nobel prize winning scientists, NASA Astrobiology Institute Director Dr. Baruch Blumberg and Dr. Robert Laughlin of Stanford University. Setting the tone, NASA's Dr. Henry McDonald envisioned an interdisciplinary, "very inclusive" community. The prepared talks of the morning session were followed by an open panel discussion in the afternoon. We welcome this initiative and its enormous potential. (Eyewitness report by Brig Klyce.)
NASA Center for Computational Astrobiology.
NASA Ames to Host Computational Astrobiology Symposium, NASA pressrelease 99-73AR by Kathleen Burton, 17 November 1999.
Computational Astrobiology for the 21st Century from SpaceRef.com, 10 November 1999.
...Is Evolutionary Progress ...Possible? is a question suited for this new mission.
November 12: Genetic Engineers use genes installed by a virus to benefit future generations of mammals. "The advance represents the first time researchers have been able to protect future generations through gene therapy for any condition, said University of Florida molecular physiologist Mohan K. Raizada."
Gene Therapy Seems To Protect Rats' Offspring, by Melanie Fridl Ross, UniSci, 12 November 1999.
Viruses... is a related CA webpage. [Next-What'sNEW about HGT-Prev]
November 10: Your Ancestors May Be Martian — A short Internet story about the paradigm shift now under way.
Your Ancestors May Be Martian, by Michael Paine, space.com, 8 November 1999.
November 9: Human Genome Bears a Virus Related to HIV. Researchers from the Howard Hughes Medical Institute at Duke University found multiple copies of an HIV-like gene in the human genome; some of the copies appear to be active at a low level. A member of the team commented, "The gene has been sitting in our genome all these millions of years, and it's in perfect working order." This news provides another demonstration that viral genes can become permanently installed into their hosts' genomes with possible long-term evolutionary consequences that are not disease-related. Indeed, HHMI states, "Because of these viral gene insertion events, genetic material from inactive viruses accounts for roughly 3 percent of the human genome." That's as much as the percentage that encodes proteins.
Human Genome Bears a Virus Related to HIV, HHMI news from the Howard Hughes Medical Institute, 9 November 1999.
Yang, Jin; Hal P. Bogerd; Sheila Peng; Heather Wiegand; Ray Truant and Bryan R. Cullen, "An ancient family of human endogenous retroviruses encodes a functional homolog of the HIV-1 Rev protein" p 13404-13408 v 96 n 23, PNAS, 9 November 1999. Abstract.
Viruses... is a related CA webpage. [Next-What'sNEW about HGT-Prev]
November 8: Dark Life — I ripped through the pages of Michael Ray Taylor's new book without stopping. This first-person tale of microscopic life in remote places has more human interest than any other science book I can recall. I had no idea that nanobacteriologist Robert Folk enjoys lunch at Hooters and speaks Italian fluently, for example. And the science is right up my alley, with lots of current, in-depth information about extremophiles, ALH 84001, possible life on Europa and related topics. Throughout the book Taylor's you-are-there caving trips are adventures with a scientific purpose — to collect samples of exotic microbes. "I gradually crossed the line from detached observer to active participant. I no longer wanted to write about research in the subterranean biosphere, I wanted to do it." I wish I could tell my story as entertainingly.
Taylor, Michael Ray, Dark Life: Martian Nanobacteria, Rock-Eating Cave Bugs, and Other Extreme Organisms of Inner and Outer Space, Scribner, 1999.
Life on Mars! is a related CA webpage.
November 5: What Does It Take for a Moon to Support Life? Andrew J. LePage gives this question deep and informative consideration.
Habitable Moons, by Andrew J. LePage, Sky & Telescope, December 1998.
Life on Europa... has links to WhatsNEW on Jupiter's and other moons.
November 4, 1999: Horizontal Gene Transfer — "Movement of genes from one species to another has until recently been considered merely an oddity of the life of some micro-organisms or a series of tricks that research geneticists have played on unsuspecting laboratory animals. Today, however, horizontal gene transfer is a rapidly growing area of research.... Ultimately, the phenomenon has the potential to profoundly affect fundamental concepts of evolutionary theory." This 500 page collection of 34 articles by eminent researchers at a 1996 conference will be eye-opening even to advocates of Cosmic Ancestry. Among the interesting findings and comments we noted:
- "The delivery of DNA to eukaryotes is a general property of conjugative plasmids and not a special property evolved for exclusively pathogenic relationships" (p 15).
- Conjugative plasmids in dead cells remain viable and can be transferred by natural means back to live cells, "thereby resurrecting genes from dead cells" (p 18).
- In addition to plasmids, transposons can be transferred by bacterial conjugation. Some reintegrate only at specific sites (p 42).
- Direct transfer of DNA from bacteria to mammals has been demonstrated (p 107).
- A plant-parasite model demonstrates that "infection leads to efficient gene transfer" (p 121).
- Bacterial uptake of DNA is "selective" (p 131).
- Nucleotide sequence variation among genes reveals that horizontal gene transfer has been a major force during evolution (p 192).
- An estimated 31,000 nucleotides of "foreign DNA are introduced and substantially fixed in the Escherichia coli genome every million years" (p 208).
- Among eukaryotes, evidence that transposable elements are horizontally transferred between distant species is now overwhelming. Until the host develops control over the acquired elements, splicing the transcript from pre-mRNA serves as an interim defense. But ultimately, "splicing of elements may result in partial to full gene expression" (p 296).
- Cytochrome-c in some plants was more likely acquired from fungi than other plants (p 328).
- "The interpretation of the fossil record seems easier with horizontal gene transfer than without it" (p 422).
- It is plausible that "genes coded for a body form in one lineage have occasionally been transferred to another to introduce a larval form" (p 437).
Our jaw hit the floor when we read this last article about larval forms. But as horizontal gene transfer is explored there are sure to be major surprises. For example, could the ability to resurrect genes from dead cells also extend the reach of life in space, or give nanobacteria an evolutionary role? This book advances the exploration considerably.
Syvanen, Michael (pictured) and Clarence I. Kado, eds., Horizontal Gene Transfer, Kluwer Academic Publishers, May 1999.
Papers by Dr. Michael Syvanen on Horizontal Gene Transfer (links to PDFs), UC Davis, 1985-2005.
"Cross-species Gene Transfer; Implications for a New Theory of Evolution," by Michael Syvanen, J.theor. Biol., 1985.
Viruses... is a related CA webpage. [Next-What'sNEW about HGT-Prev]
16 Mar 2014: It is difficult to imagine a more radical restructuring....
November 3: Fossils of primitive fish have been found in the Lower Cambrian. One fossil resembling a lamprey, and another a hagfish, were found near Kunming City, Yunnan, China. "These agnathan vertebrates predate previous records by at least 20 and possibly 50 million years.... These finds imply that the first agnathans may have evolved in the earliest Cambrian." Of course, the evolution of the first vertebrates from invertebrates was a huge advance. If this finding is sustained, the Cambrian explosion will look more powerful than ever.
Shu, D-G.; H-L. Luo; S. Conway Morris; X-L. Zhang; S-X. Hu; L. Chen; J. Han; M. Zhu; Y. Li and L-Z. Chen, "Lower Cambrian vertebrates from south China," p 42-46 v 402 Nature, 4 November 1999. Abstract.
Janvier, Philippe, "Catching the first fish" p 21-22 v 402 Nature, 4 November 1999.
Oldest fossil fish caught, BBCNews, 4 November 1999.
Neo-Darwinism: The Current Paradigm is a related CA webpage.
November 2: Does Microevolution Explain Macroevolution? has been added to the CA webpage "Neo-Darwinism: The Current Paradigm." It includes a recently discovered example of undisputable microevolutinary progress — the evolution of trichromatic vision.
Does Microevolution Explain Macroevolution?
November 1: Comets' nuclei can be blacker than coal, even though the "coma" of gas and dust they expel near the sun may appear bright from Earth. During an encounter in July, 1999, an experimental camera aboard Deep Space 1 couldn't make out the asteroid Braille and missed the chance for a closeup photo. Optical tracking devices designed for stars have a hard time seeing such dark objects, and guidance from Earth would arrive too late help during high speed flybys. NASA engineer Marc Rayman will convene a workshop at NASA's Jet Propulsion Laboratory on November 5, to consider what comets might look like up close and to propose guidelines for tracking software on future missions.
Creating the Model Comet, by Andrew Bridges, space.com, 1 November 1999.
Spacecraft fails to keep eye on job, BBC News Online, 30 July 1999.
Comets: The Delivery System is a related CA webpage.
October 27: "Life Beyond Earth" airs on PBS television November 10, with two hour-long segments, "Are We Alone?" and "Is Anybody Listening?" Scientists featured include biologist Norman Pace, paleontologist Stephen Jay Gould, complexity theorist Stuart Kauffman, neurobiologist Gerald Edelman, astronomers France Cordova, David Grinspoon and Paul Horowitz and physicists J. Richard Gott III and Freeman Dyson.
Life Beyond Earth, PBS enhanced website (with video purchase link).
October 26: A deep Internet resource on panspermia is available. This carefully categorized website lists plenty of printed references and some Internet links. It is part of "The Net Advance of Physics" at MIT.
Panspermia Theories: Annotated Bibliography, by Norman Redington and Karen R Keck.
October 21: A blood protein arose from a digestive enzyme. Scientists who found sequence similarities between two genes with different functions in the Antarctic cod, in 1997, have now found intermediate genes. Chi-Hing C. Cheng and Liangbiao Chen at the University of Illinois found "chimaeric genes" that code for both protease and antifreeze glycoprotein (AFGP). They believe these findings "confirm the protease origin of AFGP, and indicate how it was created." This is just the kind of evidence that is needed to expose the molecular mechanism behind evolution, and to most scientists the example confirms neo-Darwinism. But as evidence in favor of the neo-Darwinian (closed-system) account versus the Cosmic Ancestry (open-system) account of macroevolutionary progress on Earth, we believe the example has only marginal value for these reasons:
There are too few examples like this one. Cheng and Chen themselves call it "a rare view". Genes without identifiable predecessors are the rule.
Blood antifreeze does not constitute a complex new organ nor even a component of one. (The active part of the antifreeze protein consists of over a hundred copies, from the predecessor gene, of a sequence of only nine nucleotides.)
The example would also support the molecular mechanism behind evolution that Cosmic Ancestry advocates — the insertion of new genetic programs and recombination that is to some extent scripted.
Cheng, Chi-Hing C. and Lingbiao Chen, "Evolution of an antifreeze glycoprotein" [text] p 443-444 v 401 Nature, 30 September 1999.
Neo-Darwinism: The Current Paradigm has a discussion of the 1997 discovery by Chen et al.
October 20: Can life last forever? In a speculative article two physicists at Case Western Reserve University ponder the ultimate fate of life in the universe. They incorporate the latest research, including the surprising evidence that the expansion of the universe may be accelerating. "No meaningful form of consciousness could exist forever...," they suppose. The question matters to us, because life that is eternal in the past seems unlikely, if it can't persist indefinitely into the future. But the physicists conclude with an idea — if universes can spawn other universes as Andrei Linde [and Alan Guth] believe, "life-forms might... send themselves, or at least a set of instructions to reconstitute themselves, through to the baby universe." We welcome this modest endorsement of a way for life to outlast even the universe. And we realize that the subject needs more data.
Krauss, Lawrence M. and Glen D. Starkman, "The Fate of Life in the Universe," p 58-65 v 281 n 5 Scientific American, November 1999.
The End and the Big Bang is a related CA webpage.
October 18: Is anyone out there?
Florida Today discusses the full spectrum of ideas about life in space in a special Sunday section. There are eleven stories and a bibliography with illustrations, sidebars and Internet links — available online and in hard copy.
Is anyone out there? by John J. Glisch, Melinda Meers, Todd Halvorson, Robyn Suriano, Billy Cox, Nate Owens and Alice Garwood, Florida Today, 17 October 1999.
October 14: Retroviruses appear ancient. Nathan Bowen and John McDonald of the genetics department at the University of Georgia have found that "Cer elements" in the genome of nematodes have features similar to complex vertebrate retroviruses. From this evidence they deduce that vertebrate retroviruses couldn't have originated with mammals as previously thought. Of further interest to us, "Retroviruses and related free-moving pieces of genetic material called retrotransposons are extremely important in the genetic makeup of plants and animals, despite the fact they were not discovered until about 50 years ago. For example, half of the maize genome is made up of retroelements, and in some plants such as wheat and pine trees, 90 percent of the genome may be constructed around these 'movable genes.' Researchers now believe that these 'retroelements' are major causes of genetic mutations and are significant factors in genome evolution."
Bowen, Nathan J. and John F. McDonald, "Genomic Analysis of Caenorhabditis elegans Reveals Ancient Families of Retroviral-like Elements" [abstract], p 924-935 v 9 n 10, Genome Research, October 1999.
New University of Georgia study indicates possible ancient origin for retroviruses..., Phil Williams, EurekAlert, 13 October 1999.
Viruses... is a related CA webpage. [Next-What'sNEW about HGT-Prev]
October 14: Water not seen after planned crash of Lunar Prospector. "The controlled crash of NASA's Lunar Prospector spacecraft into a crater near the south pole of the Moon on July 31 produced no observable signature of water, according to scientists digging through data from Earth-based observatories and spacecraft such as the Hubble Space Telescope." There are several possible reasons for the negative result.
No Water Detected from Lunar Prospector Impact, by Becky Rische, NASA News Release 99-63AR, 13 October 1999.
"Bid to Uncover Water on Moon Finds Nothing," The New York Times, 14 October 1999.
October 7: More microbes survive in space. Samples from the genus Haloarcula (archaea) and the genus Synechococcus (bacteria) returned alive, September 24, from a European Space Agency "Biopan" mission. This was the third space mission in a program begun in 1994, by microbiologist Rocco Mancinelli. Additional experiments on the ground that exposed the microbes to radiation and other hazards of space confirmed their survivability. Mancinelli's experiments extend results obtained in the late 1980s, by experiments aboard NASA's Long Duration Exposure Facility. Back then, Bacillus subtilis spores were shown to remain viable after six years in space, provided they were shielded from UV radiation by only a single layer of dead cells or other naturally available protectants. Mancinelli's Biopan experiments go farther because they use microbes that do not form spores. He plans to conduct additional experiments aboard the International Space Station. Thanks, Emily Holton, for alerting us to this news story.
Sawyer, Kathy, "Hardy Microbes Appear Able to Survive in Space" pA11 Washington Post, 4 October 1999.
FOTON-12 capsule with BIOPAN back on Earth, by Peter Sickinger, Kaiser-Threde, 28 September 1999.
Life on Mars: Will It Survive First Contact, by Bruce Moomaw, SpaceDaily, 7 October 1999.
Bacteria: The Space Colonists is a related Cosmic Ancestry webpage.
NASA's interest in the microbes' survivability apparently stems primarily from its concern for "forward contamination" — sending germs from Earth to other planets or contaminating samples returned from space. Barry DiGregorio continues to be concerned about "back contamination," especially the chance that germs from Mars could be lethal on Earth. Thanks, Larry Klaes, for alerting us to this web story.
Can Martian Microbes Endanger The Earth?, by Barry DiGregorio, SpaceDaily, 5 October 1999.
Life on Mars! is a related Cosmic Ancestry webpage.
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