RE: Message in a Bottle
Good questions and many have tried to think of logical means to do the communication. Using coded files, using the "water hole" frequencies, etc. Sagan and others speculated onthe period of time a civilization might even be interested in communications. I have my opinions as to the "right" frequencies but they are at odds with the "experts". I am sure if we ever hear signals they will be the reuslt of a SETI like search or purely conincidental while we are doing something else. The problem of "encoding" a messange so any intelligent species capable of recieving it can also interpret it has been discussed as well, Drake's message send after the Arecibo refurbishment was one, Sagans graphic panels on the Pioneers and the "records" on the Voyagers are early attempts. It seems to me the only way to communicate with any hope at all of finding listeners is by casting a big net "use of a broadband (inefficient) signal" -- then hope some one out there has invented a receiver. Mickey -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] Sent: Friday, December 08, 2000 3:08 PM To: [EMAIL PROTECTED] Subject: Message in a Bottle In a message dated 12/8/2000 8:27:57 AM Alaskan Standard Time, [EMAIL PROTECTED] writes: Alien Voyagers could be zipping past the solar system as we write. The fact we have a hard time finding objects (NEO's) 1km in diameter a few million miles of earth would indicate that locating a 3-4 meter silent spacecraft missing the solar system by billions of miles would indicate that its unlikely we or anyone else would ever detect the craft traversing our region of space. Even if it came with in a million miles of earth I doubt we'd seen it. Putting a bit more philosophical thought into this brought me inevitably back to the underlying question: How do you talk to a cockroach? Consider: how does a presumeably galactic civilization, with presumeably higher intelligence than anything on Earth today, figure out how to talk across the distances of time and space, to another species that might not even be born yet? How does a completely alien creature communicate with a human, in an unambiguous way? How does it make a communication device that is big enough, bold enough, to be seen for many light years, and last for millenia? This, of course, is begging the question, why it would even WANT to do so. After all, there's no profit in doing anything for someone who is not related to you, and may be born 1,000,000 years in the future. It's all too speculative, etc. So, presuming that an alien intelligence is truly so alien as to want to make a communication with someone it does not know, and may never actually know, and presuming that it can make a communication 'time capsule' effectively, what form would it take? Clearly, little gold plaques ala' Voyager are not going to be enough. Enigmatic monoliths probably won't do the trick either. You need something big and bold, and which clearly violates normal physics enough that it will be recognized. At this point, a science fiction author might jump in and volunteer quasars or something, as that cosmic lighthouse. Perhaps messages might be encoded in viral DNA -- a self-replicating message able to survive the ages. Perhaps, as a prior writer noted, the universe might be filled with Alien Voyagers; we just haven't recognized them yet? -- John Harlow Byrne, enquirious as ever == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/ == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
The Rapid Origin of Reproductive Isolation
To: [EMAIL PROTECTED], [EMAIL PROTECTED] From: [EMAIL PROTECTED] Mailing-List: list [EMAIL PROTECTED]; contact [EMAIL PROTECTED] Delivered-To: mailing list [EMAIL PROTECTED] Date: Sat, 25 Nov 2000 21:19:06 +0100 (CET) Reply-To: [EMAIL PROTECTED] Subject: [Htech] BIO: The Rapid Origin of Reproductive Isolation http://www.sciencemag.org/cgi/content/full/290/5491/462 ECOLOGY: The Rapid Origin of Reproductive Isolation Nick Barton* The part that natural selection plays in the origin of species has long been debated. It is easy to see that if two populations are kept separate--by mountains or ocean, for example--they will eventually become so different that they can no longer interbreed successfully. Their differences may have evolved by natural selection, but their reproductive isolation is merely a side effect of changes that emerged for other reasons. This view seems unsatisfactory to those who emphasize the positive aspect of selection in evolution. Both Alfred Russell Wallace (1) and Theodosius Dobzhansky (2) argued that natural selection would reinforce reproductive barriers between diverging populations. There has been little evidence, however, that selection has in fact contributed directly to the formation of new species (speciation) in this way. Reports by Higgie et al. (3) and Hendry et al. (4), on pages 519 and 516 of this issue, provide examples from fruit fly and sockeye salmon populations showing that selection can produce the kind of isolation that separates species in the wild (3), and moreover, that it can do so within a very short time (a dozen or so generations) (3, 4). The best evidence that selection has reinforced mating barriers as an adaptation to reduce interbreeding has been indirect: Where two species encounter each other in nature, their preference for their own kind is typically stronger than for species whose ranges do not overlap (5). In their report, Higgie et al. (3) give the first direct evidence that such a pattern can be generated by selection, and that it can be generated very quickly. They worked with Drosophila serrata and Drosophila birchii, fruit flies that are almost indistinguishable in morphology and produce viable and fertile hybrid offspring in the laboratory. These sister species are found together in northeastern Australia, yet they rarely interbreed. Where their ranges do overlap, the two species differ in the mix of hydrocarbons on their cuticle (see the figure, below). The strong correlation between mate choice and hydrocarbon profiles in hybrid offspring, and in flies perfumed with hydrocarbons from the other species, shows that mate choice is largely due to the scent of these chemicals (6). Most important, in southeastern Australia, beyond the range of D. birchii where only D. serrata is found, the hydrocarbons of D. serrata change abruptly, and there is a corresponding weakening of its mating preference (3). In flagrante delicto. Gas chromatographic profile of hydrocarbons in the cuticle of the fruit fly Drosophila serrata. Individual hydrocarbons that are important for mate recognition are labeled 1 to 10. (Inset) Photograph of a male and female fruit fly (D. serrata) mating. CREDIT: HYDROCARBON PROFILE COURTESY OF M. HIGGIE; PHOTOGRAPH COURTESY OF A. O'TOOLE/UNIVERSITY OF QUEENSLAND Higgie et al. (3) set up experimental populations containing D. birchii together with D. serrata from either the north or the south of its range. After nine generations, Higgie et al. compared the cuticular hydrocarbons of D. serrata with those of control populations in which only one species was present. Little change was seen in D. serrata taken from the north, within the range of D. birchii; in contrast, D. serrata taken from further south, where D. birchii is absent in nature, tended to evolve hydrocarbons more similar to those of the northern D. serrata. (Females from three replicate populations evolved in this direction, as did males from two replicates. However, males from the remaining replicate evolved in the opposite direction.) The investigators did not test the consequences for mate preferences, but the strong correlation between hydrocarbons and mate choice in previous experiments suggests that selection has acted so as to reduce cross-mating between the species. The interpretation is simple: D. serrata in the north had long been exposed to the presence of its sister species, and so did not evolve in response to the presence of D. birchii in the laboratory. In contrast, D. serrata from the south evolved in the laboratory in the same way as northern populations presumably had in the past. Selection for a shift in mate choice is strong: When D. birchii is present, the proportion of D. serrata males from the south that successfully inseminate females of their own species is reduced by nearly 50%, whereas there is no significant interference with insemination by males from the north. Thus, the speed of the response to selection is not
Panspermia Articles - CCNet 122/2000 - 27 November 2000
From: Peiser Benny [EMAIL PROTECTED] To: cambridge-conference [EMAIL PROTECTED] Subject: CCNet, 27 November 2000 Date: Mon, 27 Nov 2000 11:43:27 - X-Mailer: Internet Mail Service (5.5.2650.21) CCNet 122/2000 - 27 November 2000 - "In like manner as a tree sheds its seed into the neighbouring fields and produces other trees; so the great vegetable, the world, or this planetary system, produces within itself certain seeds which, being scattered into the surrounding chaos, vegetate into new worlds. A comet, for instance, is the seed of a world; and after it has been fully ripened, by passing from sun to sun, and star to star, it is, at last, tossed into the uniformed elements which everywhere surround this universe, and immediately sprouts up into a new system." -- David Hume, Dialogues Concerning Natural Religion, 1779 "Still, a compelling case can be made for panspermia. A recent discovery indicates thatmicrobes can remain dormant for millions of years -- enough time to travel from planet to planet. An experiment suggests that microbes inside a meteor would not be incinerated during entry into the Earth's atmosphere. While NASA's astrobiology effort has certainly not come down on the side of panspermia, it has identified panspermia as worthy of serious investigation, along with more conventional ideas about the origin of life on Earth." -- NASA Ames Research Centre, 22 November 2000 (1) SCIENTISTS CLAIM DISCOVERY OF MICROBE FROM SPACE CNN, 24 November 2000 (2) SCIENTIST'S EXTRAORDINARY CLAIM: ALIEN MICROBE DISCOVERED NASA Ames Research Center, 22 November 2000 (3) SIGNATURE OF POSSIBLE EXTRATERRESTRIAL BACTERIA AT 83KM IN THE ATMOSPHERE Cardiff Centre for Astrobiology, 24 November 2000 (4) A BACTERIAL "FINGERPRINT" IN A LEONID METEOR TRAIN Cardiff Centre for Astrobiology, 24 November 2000 (5) AN ATMOPSHERIC TEST OF COMETARY PANSPERMIA http://www.panspermia.org/balloon2.htm (6) THE PANSPERMIA THEORY ACCORDING TO HOYLE WICKRAMASINGHE Chandra Wickramasinghe === (1) SCIENTISTS CLAIM DISCOVERY OF MICROBE FROM SPACE From CNN, 24 November 2000 http://www.cnn.com/2000/TECH/space/11/24/alien.microbe.claim/index.html By Richard Stenger CNN.com Writer (CNN) -- An international team of scientists claims it has recovered a microorganism in the upper reaches of the atmosphere that originated from outer space. The living bacteria, plucked from an altitude of 10 miles (16 km) by a scientific balloon, could have been deposited in terrestrial airspace by a passing comet, according to the researchers. Noted scientist Chandra Wickramasinghe, a participant in the study, said the microbe is unlike any known strain on Earth. The astrobiology team recovered the microorganism samples from different heights for about a year, but "want to keep the details under wraps until they are absolutely convinced that these are extraterrestrial," said Wickramasinghe, a professor at Cardiff University in Wales. NASA's Ames Research Center posted a cautious reaction to the report on its Astrobiology Web site. NASA said the finding is likely to meet considerable skepticism in the scientific community. "Aerobiologists might argue that 10 miles is not too high for Earth life to reside, a possibility that Wickramasinghe appears to accept," the statement said. However, NASA said, a compelling case can be made for the transport of microorganisms through space aboard comets and meteors. "A recent discovery indicates that microbes can remain dormant for millions of years -- enough time to travel from planet to planet," NASA said. Disputing critics who suggest that the balloon was contaminated on the ground, Wickramasinghe said the experiment took place with strict controls. He does acknowledge the possibility that terrestrial bacteria could be kicked up into the stratosphere. Living fungal spores have been discovered at altitudes of 7 miles (11 km). But observations from this and a related study suggest the presence of living bacteria far too high in the atmosphere to have originated from the surface of the planet, according to Wickramasinghe. "What is present in the upper atmosphere, critics will say it came from the ground. That is a serious possibility at 15 kilometers, but at 40 or 85 kilometers, you can forget about it," he said Friday. Wickramasinghe and colleague Sir Fred Hoyle published a draft report on the Cardiff University Web site Friday about evidence that they say strengthens the hypothesis that unusual microbes float through the upper reaches of the atmosphere. Looking at spectral data from the 1999 Leonid meteorite shower, they detected a bacterial "fingerprint" as the tiny space rocks streaked across the sky. In other words, the micrometeorites burned through the atmospheric edge in a manner that suggests they sizzled
Huygens Helps Cassini To Meet Galileo At Jupiter
Date: Fri, 24 Nov 2000 19:14:47 -0800 (PST) From: [EMAIL PROTECTED] Subject: Huygens Helps Cassini To Meet Galileo At Jupiter Reply-To: [EMAIL PROTECTED] To: undisclosed-recipients:; ESA Science News http://sci.esa.int 22 Nov 2000 Huygens helps Cassini to meet Galileo at Jupiter As the Cassini spacecraft starts its approach of Jupiter, the Huygens Probe and all its onboard instruments remain dormant. However, Huygens is not going to be totally passive. The role of Huygens in acting as a sunshield will be crucial in protecting Cassini's instruments from the heat of the Sun. Helped on its way by an Earth swing-by in August 1999, the Cassini Orbiter is now heading towards the outer Solar System for a final gravity-assisted manoeuver at Jupiter. This final planetary swing-by is vital in acquiring the velocity needed to reach Saturn, the final destination of the seven-year interplanetary cruise. The ESA/NASA Cassini-Huygens spacecraft is now approaching the giant planet. The closest approach to Jupiter will happen at the end of December this year at a distance of ten million kilometres. Even at such a vast distance the gravity of Jupiter will be sufficient to bend Cassini-Huygens' trajectory and re-direct it to Saturn. All the scientists involved in the Cassini-Huygens mission will remember 2000 as the year of the approach, observation and flyby of Jupiter. Moreover, for the first time ever, two spacecraft, namely Cassini and NASA's Galileo, will simultaneously observe Jupiter. Around the time of Cassini's closest approach, Galileo will be in the magnetosphere, while Cassini will be in the Solar Wind. Huygens will also play an important role in this encounter. The Huygens heat shield will be used to shade the Orbiter and its instruments from the Sun's heat. Huygens has happily been filling this role since early October 2000, as shown by the changes in temperature of key Huygens parts, monitored by the Orbiter, which are well within what the Probe is able to withstand (see Figure 2). Except for short periods during manoeuvres, the Probe has been shadowed by Cassini's High Gain Antenna, which until February 2000 had always been pointed towards the Sun. The Probe is equipped with a robust thermal subsystem, designed to maintain the temperature of the instruments within the allowed range throughout the mission. On the other hand, the Probe dissipates about 200 W of power during a Probe checkout, during which it gets pretty warm inside (about 35 C). Because of the super-insulation, it takes a few days for the Probe interior to cool down after a checkout. The overall temperature variations from early January until end of September 2000 of the monitored key points in the Probe are illustrated in Figure 3. Although the actual Jupiter flyby is scheduled for December 30 this year, the instruments onboard Cassini have been collecting data on the giant planet since early October. Prior to the closest approach, Cassini is outside Jupiter's magnetosphere and is providing reference measurements on the Solar Wind for Galileo, which in the meantime is flying inside Jupiter's magnetic field. Through simultaneous collection of data from both spacecraft, scientists will be able to observe, for the first time, both the environment outside and that within the planetary magnetic field of a giant gas planet. Jupiter's magnetosphere dynamics are believed to respond to changes in Solar Wind conditions. The combined data from the two spacecraft will bring a better understanding of how the Solar Wind interacts with Jupiter's magnetic field. However, Cassini and Galileo will not be close enough to see each other, even at the time of Cassini's closest approach to Jupiter they will be separated by more than seven million kilometers. Ground based telescopes will join Cassini and Galileo in studying Jupiter, in particular in observing the planet in the radio window, and in mapping the synchrotron emissions which are due to the interaction of energetic electrons with Jupiter's intense magnetic field. Furthermore, the ESA/NASA Hubble Space Telescope will be studying Jupiter's aurora in coordination with Cassini, starting 20 days before the closest approach until 20 days after the flyby. The results of all these studies will greatly improve our understanding of the largest planet in the Solar System, and for the second time after the Ulysses Jupiter flyby in 1992, a significant European participation is distinguishing itself in the observation of Jupiter and its environment. For now Huygens is just a helper in this important moment in the history of the mission, but the Probe is waiting patiently for it's big moment, which will be in four years time when it is released into the atmosphere of Titan, Saturn's enigmatic moon. For further information please contact: Jean-Pierre Lebreton, ESA-Huygens Project Scientist Estec, Noordwijk The Netherlands Tel: +31 71 565 3600 Email: [EMAIL PROTECTED] USEFUL LINKS FOR THIS STORY *
Re: On The Rise of Oxygen...
(Bear in mind, too, that some of the brontotheres of the mid Cainozoic were pretty weight competitive with at least the smaller sauropods. No doubt the brontotheres were something less than wildly active; but this shows that sauropodian mammals - while probably less likely than their dinosaurian counterparts - were not completely impossible) Then why didn't Imperial Mammoth grow 100' tall, especially when in cold climates such as an Ice Age, it would be a benefit? I suppose that steppe grasses will only take you so far... On the other hand, perhaps the combination of high body mass AND internal temperature regulation would lead to overheating? Perhaps the brontothere and titanothere had a danger of heat exhaustion? tells us clearly is that it _wasn't_ a change in environmental conditions which doomed the giant sauropod line: it was competition (in Siberia, China NAmerica) finally the Chicxulub impact (everywhere else) which did 'em in. Gary Larson suggests it was cigarette smoking that did in the dinosaurs. Another good eg of this phenomenom at work is amboreiser, the enormous ( i do mean enormous: some where the size of small bears) rat of greater Anguilla. No unusual atmospheric situation here; just a total lack of competition, so that a few, probably wet highly bedraggled rattus rattusi grew very big very fast. Now THAT, I am interested in reading about... So, you're saying that the fabled R.O.U.S. of 'Princes Bride' fame is alive and well, and hunting for large wheels of cheddar cheese on Anguilla... hmmm -- JHB == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
