initial food for thought (is that like breakfast?): if the history of the universe was scaled to a calendar year, humans would only be around for a miniscule amount of time on Dec. 31st...
the probability that life - let alone intelligent life - would arise on this rock in the middle of...well...where are we exactly? if the universe is continuously expanding, what is it expanding into?
anyway...
the likelihood that an explosion (the big bang) would take place 14 billion years ago is amazing. in that giant explosion, a bunch of (liquid) metals started spiralling around the sun. the metals converged and solidified (to some extent) into our earth about 4 billion years ago. the earth keeps whipping around the sun like the roller-skater that gets slingshot-ted(? - slungshot?) in a roller derby (tune to ESPN classics for some real excitement)
So, the earth, much like Mike Dunn - a hard-ass outer shell with a gooey center, became a platform for life (a platform, not the platform, there may be others - that's another story)
On Earth - liquid water accumulated to form one giant ocean, panthalassa = also amazing (also another long story - NOTE: there are a lot of long stories when you're discussing things on a geological time scale). the probability that one continent (pangaea) would rise enough to poke it's bald-rock-of-a-head above the surface of the ocean is nothing less than extraordinary.
with the addition of "land" to elemental cycles, a new platform to exchange...well...elements exists. how life started - who knows? (that's rhetorical - no one knows - there are theories...but i'm getting there) inception (not to be confused with conception or contraception - the letters "tra" have the opposite effect in this situation) was great (i think the top falls over at the end). how a conglomerate of matter somehow turned into the building blocks of life is unkown. furthermore, how simple life forms adapted to survive through harsh conditions AND developed an organ that can store all sorts of information and foster abstract thoughts, design tools, and other powerful functions that most of us don't even know about is unbelievable (if you don't believe it, you're foolish - it's just a figure of speech)!
the "origin" theories have their strenghts and weaknesses: Steve Pirnie shows some support for an RNA world at http://helixturn.blogspot.com/2011/03/rna-worldview.html in which RNA was the foundation for life (but he's a biochemist = bias).
i like the redox world (sidenote: i'm not biased by chemistry).
in a redox world there are simple reduction - oxidation reactions. the presence of some transition metals (probably iron - Fe) acting as catalysts made certain redox reactions more kinetically favorable. more complex reactions would find more favorable pathways until there was some sort of "kinetic trap". the thought is that these kinetic traps developed metabolic functions which grew into monkeys (i may have skipped a few steps,...sue me). Darwin thinks that the silhouettes of these monkeys slowly stood up.
origin aside: the link to the science article brings a good point in the last paragraph; there are a few different theories on the origin of life...but a more interesting question is how many times did life start before it succeeded? maybe all of the theories are plausible and happened, but one of them was able to stick around for a while!
pretty neat.
pretty neat.
in summary - the probability of this planet forming...life starting...intelligent life forming (thus we know we're here)...is low at best.
moral of the story: i think my odds in vegas are pretty good - who's in?
trivia: how many stars in our solar system? (answer is below the links)
if you are killing time at work and want to read more, check out Steve's post or these papers:
http://marine.rutgers.edu/ebme/HistoryEarthSystems/HistEarthSystems_Fall2008/Week2/Williams_Silva_J_Chem_Education_2004.pdf(ONE!! Our star; the sun - is the center of our solar system...other stars are outside our solar system)
I prefer the redox world too, but I'm absolutely bias by chemistry!!
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