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Is the Earth Special?
Hugh Pickens writes "Planetary scientists say there are aspects to our planet and its evolution that are remarkably strange. In the first place there is Earth's strong magnetic field. No one is exactly sure how it works, but it has something to do with the turbulent motion that occurs in the Earth's liquid outer core and without it, we would be bombarded by harmful radiation from the Sun. Next there's plate tectonics. We live on a planet that is constantly recycling its crust, limiting the amount of carbon dioxide escaping into the atmosphere — a natural way of controlling the greenhouse effect. Then there's Jupiter-sized outer planets protecting the Earth from frequent large impacts. But the strangest thing of all is our big Moon. 'As the Earth rotates, it wobbles on its axis like a child's spinning top,' says Professor Monica Grady. 'What the Moon does is dampen down that wobble and that helps to prevent extreme climate fluctuations' — which would be detrimental to life. The moon's tides have also made long swaths of earth's coastline into areas of that are regularly shifted between dry and wet, providing a proving ground for early sea life to test the land for its suitability as a habitat. The 'Rare Earth Hypothesis' is one solution to the Fermi Paradox (PDF) because, if Earth is uniquely special as an abode of life, ETI will necessarily be rare or even non-existent. And in the absence of verifiable alien contact, scientific opinion will forever remain split as to whether the Universe teems with life or we are alone in the inky blackness."
While most planets are obviously not suitable for life, life itself has a strong tendency to overcome the challenges of its environment. Life endures climate fluctuations, extraterrestrial impacts, and even extreme radiation, all here on Earth. While many of these protective characteristics are conducive to the emergence of higher life, life itself has already shown its capacity to adapt and overcome.
All life really needs is a liquid solvent, energy, and enough time.
"You know, the most amazing thing happened to me tonight. I was coming here, on the way to the lecture, and I came in through the parking lot. And you won't believe what happened. I saw a car with the license plate ARW 357. Can you imagine? Of all the millions of license plates in the state, what was the chance that I would see that particular one tonight? Amazing!"
Just because our "route" resulted in our "life" situation, doesn't mean that other routes couldn't produce equally valid and viable "life" conditions. We're not that special.
My UID is prime!
It seems that life, intelligence, and civilization are the things that we find most interesting, in ascending order, when discussing exobiology. And, in ascending order, much, much more difficult to achieve. In other words, simple life is almost common, complex life is rare, intelligence even rarer, and civilization the rarest of all. Each step requires more time, stability, and opportunities for differentiation, than the last. A lot of the uniqueness of the Earth, according to the article, has to do with its suitability for developing land-based life. I wonder if achieving a land-based civilization is rarer than a liquid-based one. If there are aliens sending probes over here to investigate us, maybe it's to study this weird, land-based civilization. I admit that one advantage to land-based life development is that it's much easier to form divided ecosystems on land than it is in an ocean. This could create more opportunities for divergent evolution, speeding things up if you want to see a particular result, like intelligent life. However, it seems to me that there could be situations on other planets that can create a similar effect in a liquid environment. Perhaps not common, but possible. My point is, it might be chauvinistic to focus so much on conditions that allow the development of land-based life. The other, hidden chauvinism is towards carbon-based life, but it's hard to blame ourselves for that since it's so difficult to figure out how other kinds of life could work.
Contrary to popular belief among religious fundamentalists, most atheists are not anti-Christmas. It has become more of a cultural holiday than a religious one anyway; If you asked 100 people at random what Christmas was about, how many do you think would say "the birth of Christ", and how many would say "presents", "family" or "Santa Claus"?
The people screaming bloody murder about nativity scenes and whatnot are a small but vocal minority. Usually those zealous types are former Christians themselves, the rest of us don't really care.
Maybe, but it's pretty obvious that the GP to your post is anti-Christian.
Just like reality. Ok, reality isn't anti-christian, it's just that christian beliefs are disproved by reality.
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if there is ONE case where it is true and your sample size is (nearly) infinitely large, the chance to find another case is 1.
Perhaps "nearly 1", but not 1. Case in point: There are infinite counting numbers, but only 1 even prime number (2). Surely with an infinite sample size, by your logic, you would expect multiple examples even primes?