A weblog with random thoughts and reflections on society and ecology.
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Monday, September 08, 2003
Fermi's Paradox
I was just reading a review on a book on Fermi's Paradox: If the Universe is teeming with life, where is everybody?
Form what we know about life (which is admittedly limited to this one planet), it would not be surprising if the Universe is indeed teeming with life. Life (as we know it) does seem to arise quickly under the right conditions (liquid water, organic matter). It may also not be surprising that we have had no - verified and "universally" accepted - contact yet.
Contact does require many components to be in place: (a) Another civilization that has developed technology for radio communication (since we listen for radio signals) or long-distance travel. (b) That they desire contact (they may have it as a low priority, want to protect the other civilization or themselves from the consequences of contact, or have other reasons). (c) That they are active in our vicinity (within this galaxy). (d) That they are active at a time that allows us to detect them (so their signals arrive now - when we are finally listening, or have visited during the last few thousand years, wanted their presence known, and the visits were recorded so later generations could decipher it correctly).
Civilizations may be sophisticated and advanced, and yet use neither radio communication nor space travel - their technology may be very different from ours. They may decide that technology is far less important than many other areas of life (culture, spirituality). Or they may have the technology but not desire contact or letting themselves be known. Maybe most likely, civilizations with the rights characteristics for us to detect them (compatible technology, desire) may be (a) far away from us, and (b) active at a time that does not allow us to detect them (in the past or future).
Still, I think that SETI (Search for Extraterrestial Intelligence) is one of the most worthwile efforts humans can undertake. It sets our own situation in perspective - we may be just one of a myriad of civilizations out there. And if there is contact, if we do detect another civilization, it will be among the most important discoveries of all time. It will change our own civilization forever.
09:46
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Sunday, September 07, 2003
Lynn Margulis
 Lynn Margulis, one of my favorite scientists, was interviewed on NRK recently. She is the main (nearly the only?) proponent of the importance of symbiogenesis in evolution of life.
Symbiogenesis is the emergence of a new species through the combination (symbiogenesis) of two other species. The cells in all plants and animals have evolved through symbiogensis (this is one of Margulis' theories that met immense resistance when it was first launched, and today is widely accepted).
I thought the program did a good job in explaining symbiogenesis, and in emphasizing that it does not replace natural selection in explaining evolution. Symbiogenesis explains the emergence of some species, while natural selection explains the continuation (or not) of the species. The question - and here is where Margulis' views differ from that of most of biologists - is how important and frequent symbiogenesis is. How many species, and which ones, have evolved through symbiogenesis. Is it as common as she says, or infrequent - an aberration - as others assume. One thing is for certain, none of us would be here was it not for symbiogenesis. All life we see around us is the direct consequence of symbiogenesis (all eukaryotic cells originated through symbiogenesis). It cannot be seen as an aberration.
The program also mentioned the other main theory promoted by Margulis: The Gaia theory - the Earth seen as a living system.
Again, there is a general agreement that the Earth is indeed a living system. It is, after all, a seamless whole, and it is undeniably living. And again, the disagreement is to what extent and how (processes, mechanisms). Is it self-organizing (self-regulating)? Is it self-transcending (evolving)? Is it self-healing? I believe that all the data points to a "yes" to all those questions. The Gaia Theory does fulfull most or all commonly used criteria used to define a living system. It is just difficult for us, still living in an outdated reductionistic and mechanistic worldview, to accept the idea. It is also difficult for us as it is so much larger than us - we are just one small part of it. (Note that the Gaia theory says that Earth is a living system, not living organism).
18:16
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