Life in the universe? Almost certainly. Intelligence? Maybe not
May 12, 2009 By Alvin Powell
Fisher Professor of Natural History Andrew Knoll describes the beginnings of life on Earth. Photograph by Stephanie Mitchell/Harvard News Office
(PhysOrg.com) -- We are likely not alone in the universe, though it may feel like it, since life on other planets is probably dominated by microbes or other nonspeaking creatures, according to scientists who gave their take on extraterrestrial life at Harvard recently.
Speakers reviewed how life on Earth arose and the many, sometimes improbable steps it took to create intelligence here. Radio astronomer Gerrit Verschuur said he believes that though there is very likely life out there — perhaps a lot of it — it is very unlikely to be both intelligent and able to communicate with us.
Verschuur presented his take on the Drake equation, formulated by astronomer Francis Drake in 1960, that provides a means for calculating the number of intelligent civilizations that it is possible for humans to make contact with.
The equation relates those chances to the rate of star and habitable planet formation. It includes the rate at which life arises on such planets and develops intelligence, technology, and interplanetary communication skills. Finally, it factors in the lifetime of such a civilization.
Using Drake’s equation, Verschuur calculated there may be just one other technological civilization capable of communicating with humans in the whole group of galaxies that include our Milky Way — a vanishingly small number that may explain why 30 years of scanning the skies for signs of intelligent life has come up empty.
“I’m not very optimistic,” Verschuur said.
Verschuur was a speaker at “Crossroads: The Future of Human Life in the Universe,” a three-day symposium sponsored by the Harvard-Smithsonian Center for Astrophysics (CfA), the Smithsonian Institution, the Harvard Origins of Life Initiative, and the Cambridge Science Festival.
The event kicked off with a showing of a popular science fiction movie, “Colussus: The Forbin Project,” before diving into more serious material. Topics included finding habitable planets, the rise of artificial life, human travel to Mars, and the idea that life might have a self-destructive streak. Speakers included Verschuur, J. Craig Venter, Freeman Dyson, Peter Ward, Andy Knoll, Dimitar Sasselov, Maria Zuber, David Charbonneau, Juan Enriquez, and David Aguilar.
Sasselov, professor of astrophysics at Harvard and director of the Harvard Origins of Life Initiative, agreed with Verschuur that life is probably common in the universe. He said that he believes life is a natural “planetary phenomenon” that occurs easily on planets with the right conditions.
As for intelligent life, give it time, he said. Though it may be hard to think of it this way, at roughly 14 billion years old, the universe is quite young, he said. The heavy elements that make up planets like Earth were not available in the early universe; instead, they are formed by the stars. Enough of these materials were available to begin forming rocky planets like Earth just 7 billion or 8 billion years ago. When one considers that it took nearly 4 billion years for intelligent life to evolve on Earth, it would perhaps not be surprising if intelligence is still rare.
“It takes a long time to do this,” Sasselov said. “It may be that we are the first generation in this galaxy.”
Several speakers hailed the March launch of NASA’s Kepler space telescope, which is dedicated to the search for Earth-like planets orbiting other stars. Several Harvard-Smithsonian Center for Astrophysics faculty members, including Sasselov, are investigators on the telescope mission.
Sasselov said he expects Kepler to quickly add to the 350 planets already found orbiting other stars. By the end of the summer, he said, it may have found more than a dozen “super Earths” or planets from Earth-size to just over twice Earth’s size that Sasselov expects would have the stability and conditions that would allow life to develop.
If life did develop elsewhere, Andrew Knoll, the Fisher Professor of Natural History, used the lessons of planet Earth to give an idea of what it might take to develop intelligence. Of the three major groupings of life: bacteria, archaea, and eukaryotes, only the eukaryotes developed complex life. And even among the myriad kinds of eukaryotes, complex life arose in just a few places: animals, plants, fungi, and red and brown algae. Knoll said he believes that the rise of mobility, oxygen levels, and predation, together with its need for sophisticated sensory systems, coordinated activity, and a brain, provided the first steps toward intelligence.
It has only been during the past century — a tiny fraction of Earth’s history — that humans have had the technological capacity to communicate off Earth, Knoll said. And, though Kepler may advance the search for Earth-like planets, it won’t tell us whether there’s life there, or whether there has been life there in the past.
Provided by Harvard University (news : web)
Jul 25, 2008 |
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Does the autor deny his intelligence or doesn't he have it? ;)
This is stating faith not science. There is no basis for a decision one way or the other. For one reason, the sample set is far too small.
After all, the chances of intelligent life existing in the universe are 100%. It seems counter-intuitive to me that none exists outside of Earth. We aren't that special.
Intelligent life in the universe(besides us). Absolutely!!!!
The universe is trillions of years old.
But guess what. Life existed before the universe of matter existed!!!
We can barely detect planets outside our solar system yet we are going go out on a limb and proclaim life may not be intelligent elsewhere, based on what???
The size of the universe is so vast it's almost incomphrensible where in as already stated in the above quote their seems to be an infinite amount of stars.
In other words, I call bullshit. We cannot reach this conclusion based on the technology and the information we currently have.
Have you ever seen an alien?
No?
That proves they are intelligent enough not to come here!!
why I am I responding. We are intelligent life, can we leave our solar system ??? See how foolish you sound now? I bet you thought you were being clever.
In particular, I would question how this guy decided what the average "lifetime" of an interstellar civilization is. (Exactly how many interstellar civilizations has he visited?) Okay, if you assume these civilizations last 1000 years each, then, yeah, they're always going to be pretty darn sparse. But if you assume they last a billion years each, then the universe is probably crammed with them. And how could a civilization spanning, say, a million star systems (which is only 0.00025% of our galaxy) ever go completely extinct anyway? It seems like only a war could do that -- but even then, the winners of the war would recolonize the dead zones.
...or that we lack the tools to detect other civilizations. If faster-than-light signaling exists, then it is almost certain that interstellar civilizations will use it, which explains why we pick up nothing on the EM bands we're scouring. If you had a brother on Alpha Centauri, would you want to wait 4.37 years for him to pick up the phone every time you call?
You are assuming that these aliens would have the same level of moral development as humans. But if their morals are evolved much beyond those of us animals, then they may have set up protections for "nursery planets".
Also, you're assuming that these aliens would *want* to live on planets. Empty space would be much more economical, due to its abundance. And you don't have to deal with the gravity wells that planets are stuck in. After a few million more years of evolution, who's to say whether we humans will have any further use for planets? Or even stars? Perhaps we'll colonize the space between galaxies. Nice and roomy. Of course, we'd need power generation, building materials, etc, but those should be trivial problems for a million-year-old race.
I actually think it has some merit though because even if life is reasonably common on planets with the right conditions, evolution of life does not necessarily tend towards intelligence. It tends towards ability to survive.
i was thinking however that the drake equation is used to find the possible number of civilizations in the milky way alone...this article says his numbers using that same equation account for all the galaxies including the milky way.
*youll have to forgive the expression here, I couldnt paste in what I wanted, and I cant type some of the characters in this textbox...
N = R* x fp x ne x fe x fi x fc x L
Drake equation uses:
N = 10 × 0.5 × 2 × 1 × 0.01 × 0.01 × 10,000 = 10
yes i know its just accepted that 10 stars per year in our galaxy form, but that idea came from the drake equation itself from my understanding. i could find ACTUAL evidence that only that many stars per year form. I tend to think its much higher than that.
brant-its ~3.7 billion years old last I heard...not even approaching a trillion yet
komone-there is intelligent life...theyre called dolphins :D lol
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all in all, i agree with most of you in the aspect that intelligent life is probably extremely rare, but without knowing the true numbers, the drake equation, though likely an accurate formulation to determine the true number of intelligent civilizations, is nothing more than a random number generator.
The earth has been around for a long time...it teems with life, but it is only home to a single intelligent species (and only has ever housed the one as far as anyone knows).
Judging from the history of our race, periods where the population was very low, it seems a miracle that we were able to evolve this far.
Why is it so absurd to assume that intelligence is rare? It seems like decent reasoning to me from these points alone.
It reminds me of George R. R. Martin's books that share the same futuristic universe, where humans have colonised the universe so much they have forgotten where they came from...but have never run into anything they can have a conversation with (except a sentient mud rock :P ). Plenty of animals...no intelligence.
A few thousand years hence, and we won't even resemble what we are now. We will have unimaginable powers (if we survive, of course) and we MIGHT move out into the universe, but I think that by then we will consider the universe, that which we see around us right now, to be a very boring place. I think it likely we will have moved on to other dimensions, built other universes, who knows.
I have a lot of respect for our present level of intelligence, but to any species that had the power to reach us, we would be about as interesting as slugs (no offense to slug lovers) or even simple microbes.
We have a long way to go and a bright future, but we may never meet any species at the same level as our own.
Sometimes it seems a lonely existence for mankind, but geez, we've got intelligence right here! When you get right down to it, the guy living next door is an intelligent alien. So make contact.
Heck, I am no environmentalist, but I was blown away the first time I saw a video of an elephant painting. Yeah, I know they were taught what to paint, but you can just tell that they kind of get the general idea and actually seem to enjoy it. We have more in common with elephants, a species that could be considered to be a million years or more behind us in intelligence, than we do with a civilization that is merely a thousand years ahead of us - they would appear as gods to us even if we could see them (cloaking, remember?)
were just the only intelligent species left....
gemini-i think its likely that most planets capable of harboring life as we know it probably go through the same or similar stages in development...and most likely right down to the asteroid/comet impacts and massive supervolcano events....
of course other types of life could exist, but i would expect that if life as we know it were to exist, the same conditions that exist on earth, or at least damn near it, must be present on the other planet.
Yes. These people are being extremely parochial. Are we the 'exception'? How human centric! And, certainly we are self-destructive, but, again, why should that be the rule?
Oh well, we will probably not get an answer in our lifetimes. I do hope...
The odds still don't look good though (from my pessimistic outlook :P )
Even looking on Earth, where we know at least one intelligence to have evolved, some estimates have put bacteria as 50% of all biomass on the planet. So yes, the vast amount of life is bacterial, even here. Now consider life existing in the harsher regions of the galaxy will be bacteria, such as extremophiles, and have no chance of ever evolving to higher lifeforms unless conditions improve.
Quite frankly the arbitrary number of intelligent species quoted in the article is irrelevant, whether it's one or ten or ten-thousand, the amount of bacterial life out there will still be several orders of magnitude greater.
I cannot help but agree with the article; radio intelligence (and if you're arguing lots of advanced intelligence exists, lots of intermediary intelligence will also exist) is observably rare and unless you're going to claim there is no extraterrestrial life, period, this explanation is a pretty good one.
Hell, even on earth the volcanic smokers teeming with life surprised all of us.
Claiming advanced life is not very likely, is a proof of Gerrit Verschuur's bad guesswork more than anything else.
It's silly to assume that aliens use radio to communicate. Just look at us, most of our communications now go through fiber optic cables or are narrowly transmitted. In the future communication seems much more likely to be done with lasers which can contain more information and focus it.
I also don't see why evolved civilization would have huge empires. Again looking at us we see that the more we develop the less children we have. In western europe there are already countries with declining populations due to people not wanting more than 2 children. So even if we expand to other planets who will be making all these children, and why?
Yea, that Bushie guys was so much better. He could even tie his shoes and chew gum at the same time
"Yea, that Bushie guys was so much better. He could even tie his shoes and chew gum at the same time"
lol, i'm falling off my chair.
It would appear that their views are more theologically based than scientifically based.
Out of our monumental ignorance (and in this I am referring to our brightest minds) we assume that we are somehow special and unique and we also assume that all life must be like us.
We do this when we do not fully understand ourselves and our planet let alone other planets.
I would expect that life is the norm for the entire universe.
I would not be surprised if some life forms were chemically different to all that we know, so different that our hospitable environment would be toxic to them. But as we have no experience of such life systems we have no way of knowing one way or another if this is possible.
So how can we possibly presume to declare that we and we alone are the sole intelligent life form.
Because we have no direct evidence of other intelligences we should not close our mind to the possibility that there are such life forms.
As far as Drakes equation is concerned it does not constitute even a good guess let alone a reliable formula.
We need to enormously increase our intelligence, do a lot more research and be far more patient because at the present stage of our intellectual development we find our best theory for the present state of the observable universe is 80% short of the matter it needs to support the theory.
That strongly suggests that as a species our ignorance far outweighs our intelligence.
@Luckybrandon - Bravo! I knew I could count on you to take up the slack while I was gone :)
@Everyone else - First off, whenever this topic comes up, there is one phrase thrown around that makes me giggle. "Life as we know it". Why do we assume that only carbon based life can exist? If there is one undisputable fact we HAVE learned, it's that life will find a way. Extremophiles are a prime example of this. While yes they are carbon based, they definately were not life as we knew it then. Which brings up another point. Life as we know it is in a constant state of change and revision. Just because something worked on this planet ina certain way, doesn't mean it would work on ANY other planet out there. That being said, and knowing that life will find a way, there are likely thousands of ways some form of sentient life could evolve.
We are limited to only what we have seen and studied, and honestly, we haven't even gotten that right yet.
Even if intellegent life is limited to 2-10 species per galaxy, there would still be billions of other races out there. Some more advanced, some less, and some right in the middle.
Any less advanced you can pretty much write off. Same with those around the same level as our own. If we can not leave our own solar system, it's quite probable that they couldn't either.
That leaves us with those that would be more advanced. Now you can see even here on our own planet what happens when a more advanced group gets involved with a less advanced group. I personally couldn't see a more advanced race making contact with us while we can't even manage to get along with the races we have on our own planet, unless of course they were coming in to take over. In that case sure, go ahead and fight each other, makes the invader's job easier! lol.
Couple that with how insanely huge space is, and you also have to stop and think, gee, maybe they just haven't found us yet.
With our current level of advancement, we are still mostly dependent on another race initiating contact. An advanced civiliation doesn't get to be advanced by being short sighted and stupid. If they are aware of us, it is likely contact would only be made once we have managed to get our proverbial shit together as a species. Untill then? Yeah it is kinda lonely here.
2) The understanding is pretty simple... if in a billion stars, only a few hundred million can support life, and of said life supporting planets, each supplies hundreds of millions of species, but, as per our example, only one of hundreds of millions of species achieves sentience...
It's very easily quite possible that the universe would have to be orders of magnitudes larger in order to support a second sentient lifeform, statistically.
http://www.judgex.com/
Bravo, good post.
As for coming up empty-handed in the search for other intelligent beings in the universe, perhaps those beings have advanced beyond the use of such low-tech, low-speed means as electromagnetic radiations for communications. Besides, why would they want to talk to us; after all, the vast majority of humans still delight in being carnivores, devouring billions of their unfortunate fellow creatures annually. Sign of true intelligence?--hardly.
In their star map to our galaxy, the Earth is most likely labeled with a warning marker--the dominant species: carnivorous with rudimentary intelligence; the most dangerous kind of life to be avoided.
Au-pu-
it depends on the type of life your speaking of. as humans, most just initially think of and speak about lifeforms that would be from environments like ours. In that context, it is likely right that there are very very few intelligent species that are like us (breathe comparable and same toxic gas levels as we do). i agree, there are likely other intelligent lifeforms out there based off of other chemicals than we are...thats probably the first ones wed go to war with though, as wed both literally be toxic to each other....
mro-
i agree with you whole heartedly, but only in the aspect of intelligent life like that found on earth. there may very well be other types of entirely different life out there..id be amazed if there wasnt. however, microbes like those on earth are likely quite quite common. I wouldnt be surprised at all if they found space dwelling microbed inside of gas clouds with the right ingredients for that matter.
Given that to probe the universe for intelligence of whatever variety (truly sentient or not) would require at the very least a basic form of artificial life, able to self-replicate and spread itself throughout the galaxy (surely soon within our technological grasp), it is indeed a mystery as to why we haven't been contacted by other civilisations, should they exist. The Drake equation is statistical probability (with all of its inherent weakness) for wont of evidence. A concerted effort to explore Mars or the moons of Jupiter for microbial evidence, be it in the fossil record or living, would greatly aid in the effort of providing proper and qualitative input to the Drake equation; and answer once-and-for-all, the question (and greatest of assumptions) of whether life is indeed commonplace in this universe. It will not however, answer the inherent mystery of us being alone.
Perhaps in the face of this we must ask ourselves a new set of questions?
Perhaps only once in 2049 years...
http://en.wikiped...t_story)
Nightfall by Isaac Asimov - short story, good read.
Japan isn't increasing that much. Furthermore I point you to the UN which has recently predicted Earth's population to level off at around 9 billion due to development of countries. The estimation used to be around 12 billion, but this has been decreased steadily due to increased development.
extremophiles...
not like us...
nuff said :D
N=1 ==> manifest destiny?
I personally want to meet the .74 of a species :) i bet they're cut ups...lol
So if we are unlucky, all those alien species are like the Japanese and take all their cameras with them ;-)
No animals (or Japanese people) were hurt during the making of this comment.
I would definitely agree about the radio transmitter being built by extremophiles = not gonna happen...BUT, thats not to say there isnt some form of intelligent life out there that isnt much bigger than an extremophile that could build one.
For the record though, I highly doubt any intelligent species out there is gonna be at radio transmitter technology level unless they are at a further out edge of the "blast wave" from the big bang...and since they would be moving away from us at a phenominal rate, we'll never get their signal anyways.
I concur.
I'm completely 100% certian that at least half the posters here haven't even read the article. Be the change you want to see, people.
IS THIS BASED ON THE SCIENTIFIC METHOD OR BELIEF ON DR. SASSELOV'S PART?
------>>>"...occurs easily on planets with the right conditions."
Has Dr. Sasselov observed life originating easily on any planet? Or, is this statement based on his existing evolutionary beliefs?
Ask some of your colleagues (if you work in academia) to see if they can help answer! Oh, wait a minute. They may fire you for even questioning the particles-to-people evolutionary religion...
lol
The drake equation will become more and more useful over time, as our inputs become more and more informed. It is, however, very easy to get any result you want from it, so surprising outputs should only be given credence if the inputs are reasonable. I didn't see any of the inputs listed in this article, which I found startling!
But with it being planetary bodies, one could assume it means just planets, however, I have always taken it to mean any "planetoid" capable of life, meaning planets, moons, and even possibly large asteroids in a close enough orbit to the host star.
fazer-going back to your earlier comment...we have been reasoning beings for more more than a few thousand years. I would be willing to bet 125,000 yrs. Take music as an example, I think, and to use your words, it would take a "reasoning" being/form of life to create any arts such as music, or cave art even.....you have to be able to reason to go beyond your natural survival only instincts that lower class animals have....I believe the article posted up just today stated a flute that is 35,000 years old has been found (how do ya like that "the world is only 10,000 yrs old" thumpers??).
If you reaaallly think about though, even chimps reason "what with" being able to pick out the proper color on a screen to get a banana and all :)