Cool article calculating the odds of alien life:
http://www.dbskeptic.com/2009/04/19/the-drake-equation/#more-955
The odds given are a little generous, though. For example, he estimates the odds of a civilization evolving on planets with intelligent life at 50%. I think that is way high. The evolution of intelligent life depends on a lot of unique evolutionary events:
http://aigbusted.blogspot.com/2008/09/glorious-contingency.html
My own speculation on this issue is that it is almost certain that bacteria (or some simple form of life) exists somewhere in the universe, and that complex life (things like plants and animals) probably exist elsewhere in the universe, and that it is possible that a few other civilizations exist.
I agree 50% is way too high.
ReplyDeleteI think that evolving *SELF-SUSTAINING* life is certainly plausible, but intelligence isn't necessary for that.
Intelligence seems to be the ultimate consequence of a nervous system; Although I wouldn't say it's the ONLY way. Cockroaches get along just fine (and have been, for over 350M years) with a decentralized nervous system.
Read through the entire article. The author "comes clean" at the end, and says all the previous claims were guesses and pretty much worthless. The article was actually about debunking the Drake Equation, and not about proving anything about alien life.
ReplyDeleteThe comments at the end also talk about the ratios for intelligent life and life-capable planets.
Hey Anonymous,
ReplyDeleteI did read the entire article but just thought that the initial calculation was a bit off. The author admits that at the end we really don't know, but I still think his estimation was a bit liberal.