WhatsNEW Archives, January-February 2000
HERV-W protein mediates trophoblast cell fusion |
February 29: Another gene installed by a virus appears to serve an important human function. Geneticists in Cambridge Massachusetts say that an endogenous retroviral gene may be important in human placental morphogenesis. Additional viral genes may play related roles, prompting the possibility that "an ancient retroviral infection may have been a pivotal event in mammalian evolution." In commentary, Stoye and Coffin remark, "Identification of ERVs has frequently involved serendipity. The study by Mi et al. is no exception." In Cosmic Ancestry, horizontal gene transfer by viruses and other mechanisms is essential for evolutionary progress.
Sha Mi, Xinhua Lee, Xiang-ping Li, Geertruida M. Veldman, Heather Finnerty, Lisa Racie, Edward Lavallie, Xiang-yang Tang, Philippe Edouard, Steve Howes, James C. Keith and John M. McCoy, "Syncytin is a captive retroviral envelope protein involved in human placental morphogenesis" [abstract], p 785-789 v 403 Nature, 17 February 2000.
Jonathan P. Stoye and John M. Coffin, "Reproductive biology: A provirus put to work" [text], p 715-717 v 403 Nature, 17 February 2000.
Viruses... has other examples listed under "What'sNEW." [Next-What'sNEW about HGT-Prev]
February 27: More on Stardust, the mission to return cometary dust.
Sweeping up Stardust, by Tony Phillips, Space Science News, 27 February 2000.
Going Comet Wild, by Tony Phillips, Space Science News, 27 February 2000.
Can The Theory Be Tested? is a related CA webpage.
Kidwell |
February 25: Some horizontally transferred genes target the host's germ cells and avoid the somatic cells! This is among the findings by Margaret G. Kidwell, Regents Professor of ecology and evolutionary biology at the University of Arizona. She and colleague Damon Lisch conclude that transposable elements can play a useful role in evolution, including humans', where they constitute more than 35 percent of the genome. In a 1997 article, Kidwell and Lisch had already observed, "The number of well documented cases in which element sequences appear to confer useful traits on the host, although small, is growing rapidly."
Margaret G. Kidwell and Damon R. Lisch, "Transposable elements and host genome evolution," p 95-99 v 15 n 7 Trends in Ecology and Evolution, 2000.
Margaret G. Kidwell and Damon R. Lisch, "Transposable elements as sources of variation in animals and plants" [text], p 7704-7711 v 94 Proc. Natl. Acad. Sci. USA, July 1997.
Jumping Genes Play Useful Role In Human Evolution, by Lori Stiles, UniSci, 21 February 2000.
Viruses... is a related CA webpage. [Next-What'sNEW about HGT-Prev]
A Reply from Damon Lisch clarifies this finding, 7 Sep 2001.
Nakhla contamination |
February 23: Contamination a possibility! In any case, members of the NASA team that first announced fossil evidence for microbial life on Mars now say that nine out of nine meteorites they examined are contaminated by earthly bacteria. Apparently, contamination happens faster than previously believed. Bacteria cultured from meteorite samples, including Murchison, turned out to be familiar — two of them are commonly found on human skin! The team even says that earlier isotopic evidence (supporting the extraterrestrial account) can be explained away with rapid metabolism by the contaminating germs. The racemization (gradual loss of chirality) by amino acids remains as positive evidence that the biomaterials are too old to be earthly, but this is now also questioned. Although the new research does not specifically deal with the microfossils published here on January 27, it looks like the case for fossilized extraterrestrial bacteria in meteorites has lost ground. David McKay et al. maintained, last year, that their fossils were integrated with the (Nakhla and Shergotty) meteorite matrix in ways that earthly contaminants wouldn't be. It is not clear whether this position has changed. Zhmur and Gerasimenko said the same thing about their (Murchison and Efremovka) fossils, and we have asked them to comment. Steele et al. conclude with a surprise: "We therefore, propose that... apart from some low molecular weight organic material... all other compounds could be the products of microbial and terrestrial contamination." We have previously suggested that the complex organic compounds in space may be post-biotic instead of pre-biotic. Do Steele et al. somehow almost agree with us on this point? The papers containing the contamination findings (and many other papers) will be delivered at the 31st Lunar and Planetary Science Conference, March 13-17, 2000, in Houston Texas.
31st Lunar and Planetary Science Conference, from the Johnson Space Center. The website has instructions for downloading papers. The three referenced below are from session 50.
A. Steele, J.K.W. Toporski, F.W. Westall, K. Thomas-Keprta, E.K. Gibson, R. Avci, C. Whitby, D.S. McKay and C. Griffin, "The Microbiological Contamination of Meteorites; A Null Hypothesis [#1670]." [Synopsis:] "Using 4 different techniques we have studied 9 meteorites including the Martian meteorites ALH84001and Nakhla for terrestrial contamination in all 9 we have found evidence of terrestrial microorganisms."
J.K.W. Toporski, A. Steele, F. Westall, C. Griffin, C. Whitby, R. Avci and D.S. McKay, "Electron Microscopy Studies, Surface Analysis and Microbial Culturing Experiments on a Depth Profile Through Martian Meteorite Nakhla [#1636]." [Synopsis:] "Combined electron microscopy studies and culturing experiments have shown that Nakhla became contaminated with recent terrestrial microorganisms. Additional surface analysis detected an as yet unknown organic species which may represent a biomarker."
C. Whitby, C. Griffin, J.R. Saunders, A. Steele, J.K.W. Toporski, C. Allen and D.S. McKay, "The Direct Extraction of DNA from Allende [#1732]." [Synopsis:] "We have devised a protocol for the direct extraction of DNA from extraterrestrial materials and have successfully applied it to the Allende meteorite."
Fossilized Bacteria in Murchison and Efremovka is the related CA webpage.
Other meteorites may show life on Mars is the What'sNEW item (19 March 1999) about fossils in Nakhla discovered by McKay et al.
February 23: Are the microfossils in Murchison contaminants? A recent web story suggests so. No surprise, as its author interviewed only scientists who were sceptical of Zhmur and Gerasimenko's photos, and not the Russian scientists themselves, nor NASA's Richard Hoover, the organizer of the conference where the photos were announced. The same charge, contamination, was made against the lefthanded amino acids in Murchison, in the 1990s. Subsequent isotopic analysis proved they are indigenous. Since the 1960s, when Bart Nagy published his photos, sceptics have invoked a "Catch-22" against microfossils in meteorites. If they look earthly, they're judged to be contaminants. If they don't look earthly, they're deemed nonbiological altogether. (In all versions of panspermia, earthly germs will resemble cosmic germs, to which they are related.) We will post developments as they unfold. [Thanks, Larry Klaes.]
Fossilized Bacteria Found in Ancient Meteorite, by Michael Paine, Space.com, 21 February 2000.
Fossilized Bacteria in Murchison and Efremovka is the CA webpage with microfossil photos (470K).
Amino Acid Asymmetry in the Murchison Meteorite is a related CA webpage.
February 22: Stardust collected interstellar dust today. Its aerogel collector was aimed at the dust stream overtaking it from behind. [Thanks Ron Baalke.]
Successful Start of the Historic Interstellar Dust Collection by STARDUST, by Tom Duxbury, Stardust Status Report, 22 February 2000.
Stardust Mission Status, by Ron Baalke, 22 February 2000.
Utah-Bound Spacecraft Sweeps Stardust Today, by Lee Siegel, The Salt Lake Tribune, 22 February 2000.
Spacecraft collects stardust, by David Whitehouse, BBC News Online, 23 February 2000.
27 Apr 2000: Most interstellar particles captured by Stardust are complex organic compounds.
First Direct Chemical Analysis of Interstellar Dust in Sterne und Weltraum p 326-329, v 39, May 2000.
February 18: If life can exist in the ice above Lake Vostok, thousands of metres below frozen Antarctica, who is to say that it might not be found also below the ice fields of Europa?
The ice microbes cometh, by Philip Ball, Nature: Science update, 11 February 2000.
Life on Europa... has links to WhatsNEW on Jupiter's and other moons.
February 15: The Comet Nucleus Tour (CONTOUR) mission has received approval to begin building the spacecraft. Planned for a July 2002 launch, CONTOUR is expected to encounter Comet Encke in November 2003 and Comet Schwassmann-Wachmann-3 in June 2006. The mission has the flexibility to include a flyby of Comet d'Arrest in 2008 or an as-yet undiscovered comet. The spacecraft will fly by each comet at a distance of about 60 miles (100 kilometers). The CONTOUR mission is managed for NASA by the Johns Hopkins University Applied Physics Laboratory, in Laurel, MD. The Principal Investigator is Dr. Joseph Veverka of Cornell University, NY.[ Thanks, Ron Baalke.]
NASA Begins Building Next Mission to Study Comets, NASA press release 00-26, 15 February 2000.
NASA gives go-ahead to Cornell-led 2002 mission to explore comets, Cornell University news release, 16 February 2000.
NASA Gives Green Light to Comet Mission, SpaceViews, 15 February 2000.
Discovery Mission: CONTOUR, a homepage for the mission.
Comet Rendezvous is a related section of the CA webpage "Can the Theory Be Tested?"
February 14: NEAR spacecraft achieves orbit around asteroid 433 Eros. The asteroid is only 21 miles long, so the orbit insertion reqired delicate maneuvering. The Near Earth Asteroid Rendezvous craft had sailed right by its target on the first try, in December, 1998. New discoveries are almost sure to come from this mission.
First Orbit Around an Asteroid, Space Science News, with links, 14 February 2000.
Now Orbiting, ABCNews.com, with links, 14 February 2000.
NEAR home page, Johns Hopkins University.
NEAR's Encounter with Asteroid 433 Eros, SpaceRef.com, with links.
Warren E. Leary, "Trailblazing Craft Exposes an Asteroid" [text], The New York Times, 18 February 2000.
Can the Theory Be Tested? is a related CA webpage.
February 12: Chandra Wickramasinghe and Barry DiGregorio chat with Laura Lee about life on Mars, panspermia and related topics. This interview program will be available on the Internet in two one-hour parts, February 18 and February 25, at 7PM PST, 10PM EST.
The Laura Lee Show, with schedule and Internet audio feed instructions.
Life on Mars! is a related CA webpage.
February 1: Two new Mars meteorites found — The pair had languished for twenty years in the back yard of a Los Angeles rock collector. Only a dozen Mars meteorites were previously known.
Old rocks are new Mars meteorites, by Alan Boyle, MSNBC, 31 January 2000.
New Mars Meteorite Found In California, by Ron Baalke, SpaceDaily, 31 January 2000.
Life on Mars! is the related CA webpage.
January 28: Russia plans space probe to Mars in 2005. "We hope to gather information which may help us to understand why there is no life on Mars," said Leonid Ksanfomality, of Russia's Academy of Sciences' Space Studies Institute. (Or maybe if there is life?)
Russia Eyes Mars 2005 Probe, SpaceDaily, Moscow: 28 January 2000.
Life on Mars! is the related CA webpage.
January 27: Pictures of fossils in two carbonaceous meteorites, Murchison and Efremovka, are now available. Taken by two Russian scientists, they are published in the proceedings of the July, 1999, SPIE conference organized by Richard Hoover. At right is a detail from one of the photos, showing a branched structure that resembles cyanobacteria of the genus Mustigocladus in the Murchison meteorite.
Stanislav I. Zhmur and Lyudmila M. Gerasimenko: "Biomorphic forms in carbonaceous meteorite Alliende and possible ecological system - producer of organic matter hondrites" in Instruments, Methods and Missions for Astrobiology II, Richard B. Hoover, Editor, Proceedings of SPIE Vol. 3755 p. 48-58 (1999).
SpaceDaily ran the story and pointed to our related webpage.
Fossilized Bacteria in Murchison and Efremovka is the CA webpage with the pictures.
January 27: A radiation-driven ecosystem on Europa? — It's possible, according to calculations in a new article by Chris Chyba of Stanford University and the SETI Institute. "But only direct exploration will reveal whether life on Europa actually exists."
Christopher F. Chyba, "Energy for microbial life on Europa" [abstract], doi:10.1038/35000281, p 381-382 v 403 Nature, 27 January 2000.
How life may live on Europa, by David Whitehouse, BBC News Online, 26 January 2000.
New energy in debate over alien life, by Alan Boyle, MSNBC, 26 January 2000.
Jovian Radiation Could Heat Up Europan Soup, by Mark Shwartz, SpaceDaily, 27 January 2000.
New calculations support prospect of life on Europa, by Gloria Chang, Discovery Channel Canada, 28 January 2000.
Life on Europa... has links to WhatsNEW on Jupiter's and other moons.
January 25: Yukon Meteor Blast — "A thunderous meteor streaked over the Yukon last week. Now a NASA airplane has flown through the debris cloud in search of extraterrestrial particles."
Yukon Meteor Blast, Space Science News, 25 January 2000.
Comets: The Delivery System is a related CA webpage.
January 21: Scientific American recognizes the evolutionary importance of lateral gene transfer. "...Vertical inheritance is not the only important process that has affected the evolution of cells. Rampant operation of a different process — lateral, or horizontal, gene transfer — has also affected the course of that evolution profoundly. Such transfer involves the delivery of single genes, or whole suites of them, not from a parent cell to its offspring but across species barriers." Intriguingly, the article also notes, "Many eukaryotic genes ...seem to have come from nowhere."
W. Ford Doolittle, "Uprooting the Tree of Life," p 90-95 v 282 n 2, Scientific American, February 2000.
Viruses... is a related CA webpage.[Next-What'sNEW about HGT-Prev]
January 20: Are viral influenza epidemics correlated with solar activity? Fred Hoyle and Chandra Wickramasinghe have long thought so. The current epidemic also coincides with a peak in the 11-year cycle. An article in Current Science, a weekly journal of the Indian Academy of Sciences, will reiterate the case and propose a mechanism. [Thanks, Barry DiGregorio.]
The Dilemma of Influenza (preprint), by Fred Hoyle and Chandra Wickramasinghe.
Flu comes from outer space, claim scientists, Stuart Millar, The Guardian, London, 19 January 2000.
The Dilemma Of Influenza, (reprint, in two parts) in SpaceDaily, 21 January 2000.
Germs From Outer Space!, by Robert Roy Britt, Space.com, 21 January 2000.
Influenza from Space? is a new CA webpage.
January 20: Could adenine be synthesized in collapsing interstellar clouds? A study from Calcutta suggests so. (This line of investigation supports "abiogenesis" without confining it to Earth.)
Seeds of life, by Andy Coghlan, New Scientist, 22 January 2000.
January 19: Chemical synthesis of complex organic molecules can occur rapidly in stellar environments, according to a paper presented at the American Astronomical Society (AAS) meeting in Atlanta. The authors say, "We do not understand how chemical reactions can occur so efficiently in such a low density environment." Biological causes are not considered.
Complex organic molecules form quickly in old stars, ESA, 17 January 2000.
Possible Astronomical Implications for the Origin of Life-chemical synthesis in the circumstellar environment, University of Calgary press release, 12 January 2000.
A potentially life-carrying meteoroid from an extrasolar system may have landed on Earth during the Earth's history. At least the chance is not unrealistic, according to probability calculations in another paper presented at AAS.
M. J. Valtonen et al., "Transfer of Potentially Life-carrying Meteoroids from One Planetary System to Another" [AAS abstract], 12 January 2000.
January 18: A robot to look for meteorites in Antarctica is being tested. About as big as a Volkswagon Beetle, "Nomad" was built by Carnegie Mellon University's Robotics Institute in Pittsburgh. In 1997, it slowly crossed 130 miles of Chilean desert under remote control. Now it will explore rock-strewn ice on Elephant Moraine using special instruments and software to select and gather likely meteorites. The technology will also be useful in future space expeditions. Dr. William Whitaker is the principle researcher on the Nomad project.
Warren E. Leary, "Search for Meteorites Enlists a Novel Recruit" [text] The New York Times, 18 January 2000.
"'Nomad' Finds Its First Meteorite" [text] The New York Times, 25 January 2000.
Robot hunts for space rocks, BBC News Online, 19 January 2000.
Robot Alone Via Antarctica, SpaceDaily, 17 January 2000.
Can the Theory Be Tested? is a related CA webpage.
January 14: Tower of Babel — In a new book philosopher Robert T. Pennock reviews the longstanding disagreement between evolution and creationism — and he painstakingly rebuts the creationists' case. The review is thorough and informative. For example, we learn that there was a time when the two sides engaged in meaningful dialogue. Fruitfly geneticist Theodosius Dobzhansky and creationist author Frank Lewis Marsh corresponded at length in the mid-1940s. "Marsh was one of the first creationists to accept the truth of microevolutionary change.... Dobzhansky labored to help Marsh take the next step, explaining how the evidential basis for large-scale evolution rested on inference..." (p 54-55). We also learn that such dialogue has completely ceased. Although occasional "debates" may still be staged, each side already has a fixed position that no opposing argument or evidence can influence. But Pennock can introduce us to all the major creationist participants. And he has researched lots of related issues, like, did Darwin recant on his deathbed?
Pennock's support for Darwinism, however, is less thorough. His crowning example of a computer model of evolution, to which he devotes several pages, is Tom Ray's Tierra. Pennock is apparently unaware that no evolution in Tierra has generated any lengthy new programs that would be necessary for sustainable evolutionary progress. Some virtual creatures do become longer, but they exhibit no progress and they survive poorly. Indeed, the best survivors in Tierra are have shorter instructions than their ancestors (p 106-108). Later, Pennock zealously defends Richard Dawkins' virtual "biomorphs," while admitting their limitations. In 1986, Dawkins had written that when the limitations were overcome "Evolution in the computer would then really take off...." Pennock says this prediction has now been upheld by Tierra (p 262). But Tom Ray is still looking for a way to produce "a large spiraling upwards in complexity" in his model. Apparently its evolution hasn't really taken off yet. In biology proper, Pennock adopts the mainstream position that microevolution can easily produce unlimited macroevolution.
Pennock specifically addresses creationists' attack on "naturalism," which could also be called "scientific faith" or "LaPlace's wager." It is the principle that there is nothing supernatural within nature. Pennock carefully outlines and refutes the creationist argument against naturalism authored by Berkeley Law professor Phillip Johnson. On this issue we completely agree with Pennock — if creationists want to do science, they must do it scientifically.
One may ask why creationists are bold enough to challenge professional scientists in the first place. Pennock gives the standard answer — that science has always had conservative, non-scientific, religious, sometimes powerful opposition. But in a 1997 Gallup poll, 68% of American adults thought creationism should be taught alongside evolution in public schools. What other modern scientific theory is so widely doubted? Could there be a grain of truth in the opposition to evolution? Of course there could. Science has not suddenly become infallible. Perhaps the neo-Darwinian molecular mechanism behind evolution really is inadequate for producing sustained progress. But this inadequacy would not mean that we have to abandon science altogether — as both sides in this controversy seem to suggest!
Our issues aside, Tower of Babel is the most thorough opposing review of creationism that we have seen.
Robert T. Pennock, Tower of Babel: The Evidence Against the New Creationism, The MIT Press, 1999.
Evolution vs Creationism is a related CA webpage.
Computer Models of Evolution has more about Richard Dawkins, Tom Ray and others.
January 12: Astronomers have found a pair of bacteria that might have been able to survive a trip from Mars. Curt Mileikowsky of the Royal Institute of Technology in Stockholm said Bacillus subtilis and Deinococcus radiodurans are resistant to high speeds, extreme heat and radiation. The report came at a meeting of the American Astronomical Society in Atlanta.
Did Bacteria Survive Trip From Mars?, Yahoo!.News, 12 January 2000.
Are We All From Mars?, by Kenneth Chang, ABCNEWS.com, 12 January 2000.
Did Mars Seed Earth?, Discovery Channel Online, 13 January 2000.
"Life on earth may have an unearthly origin: Panspermia," The Economist, 22 January 2000.
Bacteria: The Space Colonists is a related CA webpage.
January 11: More evidence for Europa's ocean — Changes in Europa's magnetic field indicate that the moon has an outer layer of conducting material such as a salty ocean. The Galileo spacecraft that collected the data, on January 3, continues to function after completing its primary mission to Jupiter two years ago.
Galileo Findings Boost Idea of Other-Worldly Ocean, NASA JPL newsrelease 2000-02 by Jane Platt, 10 January 2000.
Spacecraft finds alien ocean, BBC News Online, 11 January 2000.
Surf's Up on Europa?, Space Science News, 10 January 2000.
Galileo Provides Further Evidence of an Ocean on Europa, by Keith Cowing, SpaceRef.com, 10 January 2000.
Life on Europa... has links to WhatsNEW on Jupiter's and other moons.
January 10: Mars meteorite contains biologically produced magnetites? What if much of the magnetic material on Mars' surface is biogenic? The debate continues. [Thanks, Larry Klaes.]
New Life for the 'Mars Rock", by Leonard David, space.com, 3 January 2000.
Life on Mars! is a related CA webpage.
January 8: NASA will host an international conference on astrobiology science, April 3-5, 2000, at NASA Ames Research Center, Mountain View, California. Bruce Jakosky of the University of Colorado is the Chair of the Scientific Organizing Committee.
First Annual Astrobiology Science Conference, NASA Ames Research Center.
Is Sustained Macroevolutionary Progress Possible? has been submitted for presentation at the conference.
January 5: The spectrum of Pluto's moon, Charon, shows crystalline ice. This is a surprise because exposure to solar UV radiation should make the ice amorphous. Crystalline ice is evident on the moons of Jupiter and Saturn, but they are warmer than 120 K, the temperature at which amorphous ice recrystallizes. Charon's surface temperature is only about 50 K. A number of explanations are possible, including the presence of ammonia that would reduce the recrystallization temperature, or continuous micrometeorite impacts that would revaporize the ice. The spectrum also suggests that "the dark surface component is optically red," a possibility that especially intrigues us. Charon was first seen only in 1978, and distinguishing its faint spectrum from Pluto's was a feat in itself. [Thanks, Francisco Carrapico.]
Michael E. Brown and Wendy M. Calvin, "Evidence for Crystalline Water and Ammonia Ices on Pluto's Satellite Charon" [abstract], p 107-109 v 287 Science, 7 January 2000.
Eliot Young, "Charon's First Detailed Spectra Hold Many Surprises" [summary], p 53-54 v 287 Science, 7 January 2000.
Pluto's moon Charon is covered with crystalline water and ammonia Ice, by Keith Cowing, SpaceRef.com, 30 December 1999.
Observations Show Frigid Charon Has Had Some Hot Times, by Greg Clark, space.com, 30 December 1999.
The Astonishing Redness of Kuiper-Belt Objects, by Wickramasinghe and Hoyle is a related CA webpage.
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