A new theory assigns values to our scant chance of existing. So what does this mean in the search for alien life?

ET Universal Studios

We've talked in this space in the past few months about detecting the existence of Earth-like planets in other solar systems, and on the educated guesswork which goes into putting a number on the probability of intelligent life existing out there as well. You may remember that the discovery of terrestrial planets is well on its way as technology improves; and that the Drake equation—with all its assumptions—has proved to be remarkably accurate. Now another theory has been put forth about the probability of intelligent life elsewhere, but this one is centered around the numbers behind our own evolution.

Developed by Andrew Watson and published in the journal Astrobiology, the theory looks at the four steps in our evolution which Watson has deemed "critical" to our success. Those steps are: the appearance of single-celled bacteria, complex cells, specialized cells, and intelligent life with language. Each step has been assigned a likelihood within the context of the habitable lifespan of Earth, which is another innovation in this thinking.

Watson has estimated that a planet elsewhere similar to Earth—similar terrain, atmosphere, distance to its star, etc.—will have a lifespan of about five billion years during which life is possible. Given that length of time, each of the four steps has been assigned a probability of 10%, which puts us at having lucked into a 0.01% chance of coming to be over the course of our four billion year evolution.

So even if we do manage to locate and Earth-like planet, the chances of it harboring intelligent life—most especially at the time at which we find it—are astonishingly low. This is, of course, all assuming that life will be similar to ours and does not take into account the possibility of life on a gaseous giant or a frozen hunk of ice. We just don't know what could possibly be out there.

Via BBC

13 Comments

equation.sampleSize=1; //very big sample

Solace

from Ojai, California

A very good argument I heard- of the four billion years life could have appeared on our planet, it appeared sometime within the first half-billion of it being possible. If life was unlikely to appear, it probably shouldn't have happened so early in our planet's history.

- I believe it was Steven Hawking who said that, although I'm not 100% sure...

The article isn't about just life, it's about the possibility of INTELLIGENT life. In the 4.5 billion years that the Earth has existed, it has produced exactly one intelligent (as opposed to merely sentient) species. No other species has developed technology or even a written language. Think about that. 4.5 billion years. At least 10 million species of life in that time. 1 intelligent. That does not seem very easy or quick. Also, while monocellular life has been around for billions of years, plants and animals did not exist until the latest billion. And if you remember statistics, it does not mean that 1 in 10 million planets will have intelligent life. It means that each and every single Earthlike planet has the same 1 in (some unfathomable number) chance. The Drake Equation is wildly optimistic in that regard. While it would be exciting and quite possible to find simple life on other planets, the odds of SETI's success are vanishingly small. Bacteria will not be signalling us. Read the book "Rare Earth" by Peter Ward and Donald Brownlee.

I hope there is somting out there ,and I hope Just maby it's smarter than us.......stupid humans
Matthew T. Gossar

Now assuming these predictions of probability are relativly accurate, seems to me that there would be a huge chance of intelligent life being out there (finding/contacting is a different issue). .01% means that if we could find some 10 000 earths there should be an extremely good chance that one of them has developed intelligent life. yea, yea, 10 000 seems large when you consider the parameters needed for a planet to qualify as an "earth", but on the grand scheme of the universe, 10 000 is a pretty small number.....Think about how many billion stars/plantets/galaxies have already been identified and that is still only a miniscule peice of the whole pie.

"the surest sign that there is intelligent life out there is that it hasn't tried to contact us." - Calvin and Hobbes
I know, Calvin and Hobbes has absolutely no scientific credibility, but in this case, I think it has a point. Based on sublumjack's point that 1 in 10 000 earthlike planets will have intelligent life, there is a very good chance that there is life out there that is more intelligent than humans. With that level of intelligence, they quite likely have already figured out that a)we exist and b) if they tried to contact us, we would probably just wage interplanetary war against us.

In my view there is a possible flaw in this because they don't take into acount the way that basic life forms adapt to their needs. Example if there was an alien from a plant that's atmosphere was composed of co2 that would be toxic to us might not be for them. But i still feel that it is highly unlikley that there could be intelegent life. The only reason we are intelligent is because of a sereis of seemingly dull events such as man discovering fire

Well, I've finally gotten done with my diatribe about
the "Great Debate", I was playing Devil's Advocate (no
pun intended... ) to look at both/all sides of the
issue. I have mixed feelings about it. From a layman's
point of view, it's probably pretty in-depth, but from
a scientist's point of view, it's probably full of
holes, and from the religionist's point of view, it's
probably not only full of holes, but sacrilegious as
well. Ah, but such is the nature of debates. Please
feel free to give whatever advice or feedback you'd
like to give, I'd value your perspective. Also, if this
could be posted on a message board that you may
know of for other's feedback, it would be greatly
appreciated!
Indy Plume
travelbuddies04@aol.com

CREATIONISM vs INTELLIGENT DESIGN:
A VERIFIABLE SOLUTION

Although the debate on Stem Cell research is taking
political center stage at this time,
the debate on Creationism vs Intelligent Design has
just been set aside for a while and, just like
abortion, it won’t be going away anytime soon.
We still see evidence of it’s presence in newspaper
cartoons, newly published books, and lectures. This
debate will be heating up again, and is likely to get
hotter then before. That’s a good thing--as long as
it’s debated appropriately and responsibly.
A somewhat recent, well-attended debate on this
matter, which occurred in St. Louis and sponsored by a
prestigious university, was both disappointing and
disturbing, on several levels.
Disappointing because it wasn’t a valid debate,
rather, it was more on the level of a contentious
junior high
school dispute. First of
all, they didn’t talk about the same topic
simultaneously, they jumped erratically from one topic
to another, thus avoiding actual confrontation or
discussion of the pertinent issues in the debate. The
gentleman who represented the Intelligent Design
“establishment” was
a rather poor speaker, seemingly hesitant and insecure
in expressing himself. He really offered nothing more
than an expressed belief and assumption that life was
just “too complex” to be due to chance alone, without
offering any further explanation for the basis of his
support, or debate. Disturbing because the person who
represented the Creationist “establishment” utilized
“psychological warfare” rather than true scientific
debate (ie-sharp, condescending and disdainful tone of
voice, aggressive and attacking in his choice of
words, repeatedly and expressively claiming “that’s
not fair”, and reading the newspaper on more than one
occasion while the other speaker spoke). While sitting
back and watching his tactics and methods, I almost
got a glimpse of what it must have been like when the
Church Inquisitors mockingly put those of the
scientific establishment on display, and grilled them
for their “heretical, ridiculous beliefs”, rather than
proclaiming “what everyone knows to be Truth and
Fact”. Except, however, the shoe was on the other foot
this time: faith and power politics had come back
around, full circle.
The overall dispute somewhat hinted upon, (but
neither delved into nor centered upon), so many of the
different issues actually involved in the debate:
Creationism vs Intelligent Design; the teaching of
“truth and fact” vs “theory and beliefs”; Parents vs
the Education System; being told what one should
believe vs individual right to decide; power politics
vs power politics; inner vs outer experience; logical
reasoning vs emotional beliefs; to have information be
regarded as “true” before being taught in the school
vs being taught in the school before being regarded as
“true”; random chance vs intelligent guidance; science
vs religion; Church vs State; atheism vs faith; the
“world” vs “family values”; science and religion are
mutually exclusive vs both can be mutually inclusive
to find “the truth” together.
And, of course, the unspoken debate: of the
scientific establishment’s belligerent demand and need
for justice by aggressively asserting their political
right “to get even” with the Church for it’s tortuous
oppression of scientists and the scientific
establishment, for their defiance of the “Authority of
the Church” during the Middle Ages.
But, back to the present debate at hand, it’s true
that science doesn’t have all the answers and that
there are large, gaping holes–and assumptions–in it’s
explanation of life, the Earth and the universe. This
includes all the various life forms and their
processes, and to the myriad inter-relationships of
plants and animals to each other, and to their
environment, both organic and inorganic. And,
ultimately, to the creative passions and extraordinary
prowess of the human Mind. It is all extremely
complex--to say the least.
For example, how is it that scientists can say, with
such certainty, that they can explain when and where
human life began, thousands of years ago, and where
they migrated to based on a tooth or a few bone
fragments...yet we can’t figure out who killed Nichole
Brown Simpson despite all the immediate, fresh
evidence in the present, state-of-the-art forensic
science, exhaustive testing, and equipment at our
present and immediate disposal?
And, speaking of migration theory being based on
selected few bone fragments, the OLDEST human bone
fragments were probably deposited and fossilized where
the majority of humans probably lived at that
time--along the ocean shores when sea levels were much
lower, during the Ice Ages--and which are presently
far under water after the Ice Age melted and the
waters rose. And why do they say that humans evolved
and migrated out of Africa? What’s so special about
Africa? Why didn’t we, and life, evolve everywhere
throughout the planet, at the same time? Isn’t that
curiously odd?
So, the objective findings, and therefore the
results and theories, are skewed–we just happened to
find the easiest ones to find, not necessarily the
oldest upon which to base what actually occurred with
human origins and migrations.
And how can scientists say that the entire universe
came “from nothing” and traveled out “into nothing”,
and that it is “infinite”, without rationally
explaining how? That kind of talking sounds exactly
like the faithful, and non-rational, religious, whom
the scientists scorn for their irrationality.
What was there before the, supposed, Big Bang? One
theory postulates that there were some kind of walls
created by (yet another unproven theory of) super
strings, and a Big Bang, or the explosion of
super-intense energy of the entire universe, was
created from the infinitely small point where the two
walls touched each other (much like the intense spark
that’s created when a positive and negative electrode
contact one another), thereby creating the entire
universe on one side of the walls at that point. If
that were the case, where did the super strings come
from? From another universe created by the contact of
a previous super string, and one before that, ad
infinitum, much like a domino being struck by the
domino proceeding it, in a long line of dominos? But
where did the original super string come from? The
theory never really solves the basic problem, it just
pushes it further back in time to the same question.
It’s rather similar to a particular religious point of
view where the “world” rests upon the back of a
turtle, with that turtle supported by a larger turtle,
which is supported on the back of an even larger
turtle, ad infinitum....
And, let’s face it, scientific “facts” or theories
are based and formulated as much upon politics and
popularity as it is on objectivity and evaluation.
Can science truly explain everything accurately?
What about the once-held scientific belief that mice
spontaneously generated out of boxes filled with rags
and grain and placed in a dark attic? And, while we
understand the processes, and use, of electricity,
time, fire and life, what about the fact that we still
can’t describe what they are, fundamentally.
And what about the scientific assumption or premise
that all life on earth is possible with enough time
and random mutations? How, and by what process, did
DNA first get correctly organized and arranged to
create the very first life forms?
Likewise, religion too has shown that it is a very
poor in accurately describing the realities of the
universe, as well. For example, every religion claims
that their religious views are true, and every other
religion's view is not only wrong but, oftentimes, an
amusing myth as well, ie--that the universe revolves
around the earth because that is, obviously, what is
seen with our own eyes; that uncontrolled movements of
a person's arms or legs are due to "St. Vitus' Dance";
that the human spirit is reincarnated as a cow; that
gods live on mountain tops; or that the sun is pulled
across the sky by flaming chariots. And why do people
consider these things to be “true, or fact”? "Because
that's what someone wrote or told us throughout our
history; because that is our tradition; because that's
how we feel and, therefore, believe; because it's the
unknown and beyond our knowledge so it's our way of
creating order and understanding and we must have
faith in it to feel safe, despite any other objective
facts we may learn."
Just look at how vastly different each religion
describes the origin of the universe, and how deeply
and fervently they believe that it is "the only Truth
about reality".
The Intelligent Design establishment's assertion
that there must be a creative and divine Intelligence
guiding life and the universe “because it's just too
complex to be due to chance alone" is understandable,
but it's just too simplistic (and a rather childish
argument as it's debate). What kind of proof is that?
But in all fairness, let us take a closer look. Life
and the universe IS extremely complex--to say the
least--and because the most complex computer and
machines we can create are absolutely NOTHING compared
to the complex, intricate workings of life, the
universe, and our minds--and those computers and
machines were definitely not created by chance alone!
Fundamentally, computers are nothing more than
chemical parts and bits of electricity, yet it
requires the essence, and unique configuration, of the
software and hardware--as well as a cognitive being to
create, and give it a force of, purpose and direction
to function, perfectly. Realistically, what is the
probability of a computer gathering itself together
(given enough time and energy), function as a
computer, and replicate itself for future generations,
by itself? Or, a better example yet, what is the
realistic probability of a group of sentient monkeys
sitting in a room with a typewriter being able to
create Shakespeare or the Treaty of Versailles, motion
pictures or music, or even the pure conceptual thought
of geometry–which is demonstrated in the actions of
nature--given enough time and energy?
The Creationist Establishment’s
fundamental assumption and belief that all life is
strictly due to natural selection and random chance of
genetic mutations--given enough time– is also
understandable, but it doesn’t look at the whole
picture. It’s an extrapolation and projection of the
whole from it’s viewing of individual, selected
“parts” or events. Where is the real scientific study,
or proof, behind this assumption? Has it ever been
tested? Where are the tests that were conducted that
shows this to be a fact of nature, and not just an
assumption?
But in all fairness, let’s look at it closer.
Science is
profound in it’s
ability to, realistically, describe the universe as
well as life and it’s processes much better than
religion ever has (remember the Dark Ages?), despite
all it’s gaps and assumptions. And it’s ability to
harness this knowledge–why, just look at all that
we’ve been able to discover, and accomplish! Human
beings, who are relatively helpless compared to other
animals, have obtained the power to actually fly
objects far beyond our solar system, to discover and
peer into--and even harness--the depths of individual
atoms.
As dichotomous as Science and
Religion are, or seem to be, they are actually the
opposite faces of the same coin. How can you totally
separate Nature and Nurture, and completely exclude
one or the other, in establishing the form of
personality? How can you totally separate Science and
Religion, and completely exclude one or the other, in
establishing life and human consciousness? And who
says that they must be mutually EXCLUSIVE? Where is
the proof behind that assumption or belief? After all,
weren’t we able to accept the fact that light is both
a particle and a wave at the same time? The problem
that it’s difficult to see both sides fully at the
same time, on such a profound scale.
So, how do we resolve
this problem of dichotomy, opposite viewpoints and
opinions? The Scientific community assumes and
believes–fundamentally–in the scientific method and
evolution as being the cornerstones of it’s entire
philosophy. So much so that it has never applied it’s
scientific methods to test the randomness of evolution
itself. How does it absolutely know–as a fact–that
life and the universe is strictly due to chance alone?
It doesn’t, it just believes it to be fact and truth
and is unwilling to look at it further. They believe
this as blindly and fervently as the religious believe
in their faith of Divine Intelligence. And the
Scientific community’s argument that the Intelligent
Design proponents don’t offer any proof to their
arguments, also applies to the Scientific community
itself, as well.
So how do we resolve this
conflict? One suggestion is that we gather and
establish a massive data base of all the information
we know about life, it’s internal processes, it’s
interrelationships of plants and animals to each other
and to the environment (both organic and inorganic),
as well as the diverse fields of quantum mechanics,
the forces of energy, and the processes of the
universe itself. (We have already started this, to
some degree, by working to establish an internet-based
‘Encyclopedia of Life’ to list and record all of the
different species of life on our planet). Then--with
the use of chaos theory, probabilities and super
computers--we conduct massive, detailed data mining
programs to correlate, compare and contrast all of the
information in order to study one simple hypothesis:
to determine or prove the statistical chances of
whether or not life as we know it is strictly due to
chance alone, or by some kind of metaphysical
intelligent guidance or force. (Note: for those who
may know this, the answer is not “42").
It’s true--this is not a feasible
option or solution. The idea, and magnitude, of
gathering and programming all of this data, as well as
creating the software to comprehend and process it, is
just too daunting to even seriously be considered. But
why not? If Wal-Mart can create and use supercomputers
to keep track of it’s massive worldwide inventory and
shipments–in real time--and we can apply our vast
resources to comprehend, design and create
superconducting supercolliders to see if we can find
particle(s) of nature--and can use the motivation and
rationale of justifying the expense of building one
because we need to beat the other country who’s also
building one--why can’t we build one to find an answer
to this one essential and fundamental question? At
least it would be a start. It would be a start to
solving this debate, even on a small scale, rather
than “socially fighting our selves to the death” to
establish who is ultimately “right”, much like the
proverbial two cats whose tails are tied together and
hung over a clothesline to see which one has the
ultimate “right” to survive or be “the truth”, while
the other one has to be defeated or die because it’s
“wrong”.
Most people don’t know,
or publicly acknowledge this, but Darwin, the Father
of Evolution and the Creationist’s belief system, was
himself not an atheist, and did not mutually exclude
science and religion. He was a man who devoutly
believed that God was the source and creator of the
evolutionary process. So who says that it can’t be
both, if Darwin is able to believe and publicly admit
this?
Could it be
possible that the thesis, “Scientific Spirituality:
Discovering the Living Universe” may be an actual
unifying theory for the two dissonant and disparaging
groups? So, in summary, will there be critics and
opponents of this idea? Of course–it’s a new idea, and
new ideas, like change, are always resisted,
criticized and challenged if, for no other reason,
than because they’re new and they challenge our
(comfortably secure) belief system. Will some
challenge “the biases” that they might see in this
article? As you can see, the pros and cons of both
sides have been adequately and appropriately reviewed.
The only question for the critics are, what solution
do you have to take it’s place (after all, as the
saying goes, “complaining is volunteering”).

As Albert Einstein once said--
“Imagination is more important than knowledge”.

Thats the same as a scientist telling you, "you have a 1% probability of winning this game" and then you go and beat it 500 times.

It's more of a 50/50 chance for every planet before we know for sure, because although there is "only" one species on this planet that is "intelligent" doesn't exactly mean we have prime conditions here. In fact, for a planet with life on it that rather seems to be the opposite of true.

The idea that technology and a written language makes us intelligent, also appears to be a slippery truth.

As a species, we don't even appear to know for the most part how it is to live WITH the planet, but rather seem to be steadily working against it.

Plus, if I where to mark a species as being intelligent, It would be a species that knows how to work TOGETHER for the common good, not a "where one person looses another person succeeds"
society.

As a species, we have been destroying our habitat and destroying other species habitats. I'm sure that with our guidance and help nearly every species on this planet would have a chance to evolve into a state equal to our own.

I don't think there is life on other planets. Life is a miracle. It's like a fantasy sci fi geeks have. Always looking to the stars and dreaming instead of dealing with the here and now on earth.

Sorry, but that's nonsense. You really don't understand statistics at all if you think it's anywhere near 50/50. Good luck winning that game 500 times if your probability is 1%. You probably won't even win once in a thousand times. We do have prime conditions here. Again, read the book "Rare Earth." Look at the other eight planets in this solar system. Not so much as a bacterium found yet. Look at all the extrasolar planets found to date. No reputable scientist would tell you life is possible on them, given their masses, orbits, etc. It takes a lot to make a planet hospitable to sustained evolution, as the book above tells if you're just willing to read it rather than propound some pseudoscientific "if we all helped other species" theory.

If technology and language don't imply intelligence, how will we ever find another intelligent species? They wouldn't be able to communicate meaningfully with no written language to record and transfer complex knowledge and even if they could, they wouldn't have radios.

You claim every species on the planet could evolve intelligence if given a chance. The Homo genus has been around for about a million years. Dinosaurs ruled the Earth for 160 times as long but never showed any glimmer of intelligence and probably never would have. Some species that old are still around today. Know any intelligent crocodiles? Birds? Sharks after over 400 million years in the oceans? Even cetaceans have been around for almost 40 million years, yet nobody would expect a whale or dolphin to understand complex concepts.

"and that the Drake equation—with all its assumptions—has proved to be remarkably accurate"
What the heck is this sentence supposed to mean? You obviously don't understand the intent of the Drake Equation.

The Drake Equation originally had no numbers with it - it was only proposed to illustrate the point that one *could* do some work and try to fill in enough numbers to get an estimate of how much (intelligent) life there is in the universe. However, the vast majority of the numbers (and variables, for that matter) involved in this equation are highly debatable and therefore there is no one "accuracy" you can apply to it, as there is no, one agreed upon form of the Drake Equation.

Furthermore, seeing as we only have one data point (or maybe eight, if you count all of our planets and assume that they are lifeless), even if you could fill in all of the other numbers in the Drake equation, it would be impossible to assess its accuracy as we have no definitive way of knowing which of the planets/stars/galaxies we observe actually have life.

Spiritof76, while your point makes sense, he was not stating that technology and language do not imply intelligence, but simply that they do not constitute intelligence,


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