Life only got started one time here on earth....."The most profound and true statement that ever was"...as Mr Byrne has expressed it..
Does anyone even dispute that? If true, I believe it is, this seems to be the 800lb ‘gorilla in the room’ on many issues discussed here at AO... Why hasn't life happened over and over on a planet so perfectly suited for live? Why not every day and in the creek behind my house?. And why is this not the most important (and least likely) component in the Drake equation of probabilities for ETL?
Like most of the readers here, I dearly want to believe that we are not alone...that SETI will find more than a proverbial hum. But I read about the chances of spontaneous self replication with enough zeros to go around the block...and it only happened ONCE here on this floating smorgasbord for life !
If I use that 'one-in-a-trillion-trillion' chance of life just getting started, factored with the probability of having all the natural resources needed to advance a civilization, times the liklihood of the physical configurations required to manipulate those resources (thinking smarter dolphins and elephants), I come up with an absolute zippo chance of aliens flying around our galaxy and stopping here at some point in history. Not 00001%. More like a ZERO and I don’t need all the other factors to get to zero and no we sure don’t qualify.
In fact I think we could be the most progressed life form within our galaxy. Nothing wrong with this thinking and It makes all of mankinds achievements that much more fascinating. I enjoy Ancient Aliens (and websites such as this) as much as anyone but I attribute it to our Amazing Ancestors, all these special people who came before us.
A millennium from now, with deep and intimate knowledge of our Milky Way, the notion of us as mere midgets amongst a galaxy full of planet hopping aliens will be parked in the same space that flat earth thinking occupies today.
In the meantime, there’s still money to be made on the contrary.
I get what you mean, and I can follow the reasoning....I just don't wannnnnaaa! In the words of Fox Mulder, "I want to believe!" :)
love, light and blessings
There are those who hold the opposite view, that the odds are staggeringly in favor of extraterrestrial life despite any formal contact (ie. Fermi's paradox). Nobody actually knows how to calculate the odds though, so such arguments are hubris.
The scientific view of how life began on earth is murky and littered with conjecture
Our knowledge of the parameters for life in this universe is by no means complete
Science has NO IDEA how large the universe actually is
Life may have less to do with chance than some think
Extraterrestrial life may know about us but have no desire for contact
We may have already had brushes with non-anthropomorphic extraterrestrial life and not recognized it
i agree with Rizzman. i recently saw adocumentary on Nova about how the Earth has had 2 complete ice ages freezing the entire surface of the Earth killing everything. according to this documentary life has evolved 3 times here. i am no expert, but they are. maybe they are right maybe not. while i believe there is life elsewhere in not just the Universe but this galaxy, there is not one shred of evidence that aliens were here or are even coming.
I was really only implying the sheer unlikelyhood of life buzzing around our own 200b planets and intervening in our accomplishments, aka ancient aliens..
Who we are and what we have accomplished in a relative nano second should be the first thing on everyones mind and yelled from every rooftop. To me, that's even more profound than ET, and it's real, not wishful thinking...
Wishing I knew a little more....
> I was really only implying the sheer unlikelyhood of life buzzing around our own 200b planets and intervening in our accomplishments, aka ancient aliens..
I was apparently reading too fast and misunderstood.
While I don’t disagree with your basic point, I think there are other ways to look at it that we should keep in mind.
You said, “I read about the chances of spontaneous self replication with enough zeros to go around the block...”
This is an important point; as you say, there are enough zeros to go around the block. Basically what that means is, even when all the necessary elements are present and the environment is calm and non-destructive—the proverbial “primordial soup” cooked to perfection, in other words—the likelyhood of the most basic elements of life arising spontaneously is extremely close to zero.
A good rule of thumb for translating probability calculations to the real world is, the lower the probability of a given event, the longer the span of time necessary to allow for it to occur. Probability calculations are made without considering duration, so the number is telling you the probability that something will occur at any given moment—in the case of the spontaneous formation of life, that probability is extremely low even in favorable circumstances. But once you factor in a time dimension, you see that even for the most improbable of events, the more time that passes without the event occurring, the more probable it becomes that it will occur.
When considering the improbability of the spontaneous formation of life, all those zeros stretching around the block are telling us that a very long time span is needed in order for such an extremely improbable event to become probable. After that, if more time passes without the event taking place, it actually becomes more and more improbable that it won’t happen.
What’s interesting in the case of life on earth is the fact that no such large time span seems to have taken place. The first, most rudimentary life forms appeared here almost as soon as the earth had cooled and solidified from its original formation. This is why Francis Crick, one of the original discoverers of the double-helix structure of DNA, speculated on the idea of “directed panspermia”, which says that the “production of living systems from molecules may have been a very rare event in the universe, but once it had developed it could be spread by intelligent life-forms using space travel technology.”
That’s something to think about. It would also explain why any alien visitors would be visiting—we’re all part of the same cosmic family, having all had the same genetic great-to-the-Nth-degree grandparents.
Another thing to keep in mind is the various evolutionary “explosions” which appear to be present within the fossil record. While not nearly as improbable as the spontaneous formation of DNA, the evolution of entirely new species from more rudimentary life-forms is still extremely improbable. As such, one would expect large spans of time would be necessary in order for such a thing to take place.
But again, that isn’t what appears to have happened in many cases. The record seems to show long periods of time where almost no evolutionary development at all takes place. Then there is a cataclysmic event that wipes out a lot of life on earth—a mass extinction—followed by an ”explosion” of hundreds or thousands of entirely new species which seem to show up all at once….followed by another long period of very little evolutionary development. (One of these is known as the “Cambrian Explosion”, for instance.)
This seems to suggest that something other than mere chance is involved in the development of life, at least here on earth.
That’s my two cents. Great topic of conversation, by the way….have enjoyed reading the thread and everyone’s views on this subject.
Nice post Tsurugi. Have you seen this? http://www.huffingtonpost.com/2015/02/03/aliens-send-space-seed-to-earth...
Hah! I knew about the meteorite mentioned in the article, but I never heard of Wainwright's discovery. That's awesome, thanks for the link!
It's like....aliens are shooting microscopic full-metal-jacket biopaintballs at us, or something.
WE SHOULD SHOOT BACK.
...sorry. I'm from Texas, so....
Most scientists don’t agree that life happened one time. The simple fact is that there’s no way of telling if it only happened one time or if it has happened millions of times. If life were to spontaneously come into existence at this very moment there would be no way for any of us to tell. It would be microscopic life and we probably would not be able to differentiate it from other life even if we happened to stumble across it. If we ever encounter an alien civilization they will probably look a lot different than us, but their primitive organisms might be very similar to ours. DNA/RNA could be the norm. Perhaps when life happens to come about, it comes with a similar makeup which would make it impossible to differentiate as NEW or as ALIEN.
It could be that it has happened several times in the past but was killed off by existing life or simply evolved to blend in with existing life. There would be no physical evidence available in the fossil record...and besides, you can’t determine if life is new or alien based off a fossil. Fossils don’t show genetic coding(or lack of). It could be that the first organisms to use DNA were actually new life rather than having evolved from previous life. It could be that at one point in time life died off from an impact but the planet was reseeded with new life.
We simply don’t know if life happened once and any scientist that claims to know this is simply not well informed.
For me it’s a numbers thing. Starting with our galaxy of, say 200b stars and using any realistic probabilty factors in the Drake equation we quickly get down to manageable numbers of 1 to maybe 10,000 chances of life capable of spitting out radio waves coincidal with our existence here and now. I feel like there would be at least a dozen more ‘components’ (or rewritten completely) to get to galaxy roaming, planet hopping, earth visiting, life we would recogonize, space invaders that Georgio is so certain of. Life being SO immeasurably difficult to get started is just a part of the equation and 200b is just not a big enough starting point. We are so lucky.
‘In the universe’ of course is a whole nother story.
Wishing I knew a little more....
Rizzman, i checked out that link. thanks because those pics of the fossils in that meteor look like some sort of microscopic life. it supports my belief that there is life out there. proof for me. as to how it got here, if it was purposely sent or if some giant meteor splattered another planet and that chunk managed to survive entry to our atmosphere, who really knows for sure? to me those little plant like fossils are/were life! to convince me it is aliens shooting it here, i’m going to have to see a spaceship or ray gun. anyway eye-opening stuff that’s for sure
Given our estimated age of the universe, and the much younger age of the Earth, there would have been plenty of time for life to have evolved elswhere, and spread to Earth through panspermia. Earth was formed relatively recently, and again, there was plenty of time for the evolution of highly advanced races who may have indeed employed directed panspermia to seed other worlds. Until we have more definitive evidence, however, it is a fascinating scenario, but a highly speculative one at best. With that being said...”I too want to believe”.
R. Lee Bowers