The Odds of Life and Intelligence

  • Published on: 18 May 2020
  • If we re-ran Earth's clock, would life arise again? Would another civilization eventually evolve? Astrobiology is faced with trying to contextualize our place in the Universe using just a single data point. But even a single data point contains information. The key to unlocking it is a careful understanding of the selection biases at play and intricacies of Bayesian statistics. Today, we're thrilled to present to you our explainer video of a new research paper led by Prof David Kipping that provides a direct quantification of the odds of life and intelligence on Earth-like worlds, based on our own chronology. Presented & Written by Prof. David Kipping.

    This video is based on research conducted at the Cool Worlds Lab at Columbia University, New York. You can now support our research program directly here:

    Previous episodes to catch up on:
    ► "Watching the End of the World":
    ► "Why We Could Be Alone":

    ► Kipping, D. 2020, "An Objective Bayesian Analysis of Life’s Early Start and Our Late Arrival", PNAS:
    ► Spiegel, D. & Turner, E., 2011, "Bayesian analysis of the astrobiological implications of life's early emergence on Earth", PNAS 109, 395
    ► Carter, B. 2007, "Five or six step scenario for evolution?", Int. J. Astrobiology 7, 177 :
    ► O'Malley-James, J. et al. 2013, "Swansong biospheres: refuges for life and novel microbial biospheres on terrestrial planets near the end of their habitable lifetimes" Int. J. Astrobiology 12, 99:
    ► Bell, E. et al., 2015, "Potentially biogenic carbon preserved in a 4.1 billion-year-old zircon", PNAS 112, 14518:
    ► Smith, H. & Szathmáry, E. 1995, "The Major Transitions in Evolution", Oxford, England: Oxford University Press
    ► Schopf, W. et al., 2018, "SIMS analyses of the oldest known assemblage of microfossils document their taxon-correlated carbon isotope compositions", PNAS 115, 53:

    Video materials & graphics used:
    ► Berkeley Lab/Sloan Sky Digital Survey:
    ► Life Beyond by melodysheep:
    ► K2-18b animation by ESA/Hubble, M. Kornmesser:
    ► Earth 4k by NASA/ESA/M.Kornmesser:
    ► Galaxy spinning animation by Huy Trường Nguyễn:
    ► Earth timelapse from NASA DSCOVR EPIC:
    ► Animation of GJ1214b by ESO/L. Calçada:
    ► Roulette table by steveh552:
    ► Sky timelapse by National Geographic:
    ► Milky Way animation by Stefan Payne-Wardenaar:
    ► Outro by Carl Sagan from his book Pale Blue Dot
    ► Thumbnail image licensed through, image #8872987 by RAStudio

    Movies/TV scenes used:
    ► Agora (2009)/Focus Features
    ► The Martian (2015)/20th Century Fox
    ► Noah (2014)/Paramount Pictures

    Music used in chronological order:
    ► "The Sun is Scheduled to Come Out Tomorrow" ( by Chris Zabriskie (; licensed under a Creative Commons Attribution license (
    ► "Cylinder Five" ( by Chris Zabriskie (; licensed under a Creative Commons Attribution license (
    ► "Cylinder Two" ( by Chris Zabriskie (; licensed under a Creative Commons Attribution license (
    ► "Stories About the World that Once Was" by Chris Zabriskie (; licensed under a Creative Commons Attribution license (
    ► "Painted Deserts" by Shimmer, licensed through

    And also...
    ► Columbia University Department of Astronomy:
    ► Cool Worlds Lab website:

    Latest Cool Worlds Videos ►
    Cool Worlds Research ►
    Cool Worlds Long Form Videos ►
    Guest Videos ►

    SUBSCRIBE here:


    #AreWeAlone #Astrobiology #CoolWorlds
  • Runtime : 28:13
  • are we alone could we be alone probability that we are alone odds that we are alone probability of alien life chance of aliens chance of alien life is there life are there aliens astrobiology life universe statistics alien life bayesian statistics aliens bayesian statistics life


  • Cool Worlds
    Cool Worlds   1 years ago

    Thanks so much for watching everyone, make sure to like/share/subscribe if you enjoyed this! This has been a major research effort over the last year and I'm thrilled to finally share it with you. We have so many other exciting projects on the horizon but only so much in the way of research resources to pursue these thrilling ideas. If you want to support our research, you now can through the Columbia Just Giving platform - - thanks for anything you can do to help us unravel the Universe's secrets!

  • Frenk
    Frenk   10 hours ago

    What if the expansion phase of the universe is causing life to emerge and evolve, too much noise/activity clump together otherwise. Complex atomic arrangement (life) is just a recent '' phase '' of the universe.

  • Boik
    Boik   1 days ago

    Cool Worlds and great stuff. Just spending time with eloquent, well studied, logical people is refreshing as hell considering the number of low functioning humans still thrashing about in the netting of Bronze Age religions. Fascinating, thought provoking as always.Thank you sir.

  • Hans de Ruiter
    Hans de Ruiter   1 days ago

    The odds off live is pretty high. Creatures are found at remarkable palaces where it shouldn't exists. Intelligence is a quit other thing. A microbe (or greater) can be smart in its own environment. but is not capable to emit a strong signal to us. Let alone to build a star ship. We compare it to much with our own history. Maybe they didn't invented the wheel or didn't have to. They could have other capability’s unknown to us. We see too much intelligence like our own. This Bias is hindering us. They must behave like us to be intelligent? Maybe they aren’t curious what's out there. We do. Is this a part of intelligence? Maybe not. They are content with their ways. Intelligence does not have to be our way of thinking. That's the mistake here. We think too much like us. Greeting from planet Zilgko. We did found this earlier. We make also this mistakes. The concept bodered our civilization also. We aren’t you call the grey’s A pestering race with no respect.

  • Bud White
    Bud White   6 days ago

    27:00. You sound pretty optimistic that our descendants will answer this question when the current descendants believe there are 20 genders and don’t know which bathroom to use. Humanity has peaked, lt’s all downhill from here

  • AVClarke
    AVClarke   6 days ago

    My belief is microbial life is likely common on many worlds, but intelligent life is uncommon.

  • jj stop raging
    jj stop raging   1 weeks ago

    See that’s you’re problem, just because you can’t think of any probabilities you automatically think there’s no way there can be nothing out there

  • Klaas Deforche
    Klaas Deforche   1 weeks ago

    We will know the answer soon enough. All we need is a good telescope.

  • Sean Cooney
    Sean Cooney   1 weeks ago

    There is one problem with the 4.1 year time frame is there is one external factor that wasn't considered. That factor are large extinction events. I wonder how the odds would change if that was factored in.Based on the fossil record there have been 5 large extinction events in Earth's history. For fun let's say the the last major extinction event didn't happen the cretaceous event aka the dinosaur Extinction .. how would of that effected the time it took for a intelligent lifeform to evolve ( yes I know there was a star trek episode with the same idea).If that would of sped up the process let's say by 40 million years that would increase the odds of intelligent life evolving. Maybe the great oxidation event didn't occur 250 million years ago ... How much would that of sped up the evolution process. Also we are just looking at stars like our own. In the comments section there had been mention of brown dwarfs. While less likely they would be around much longer then our star and while more prevalent to solar flares, a planet close enough would be more then likely tidally locked and would have areas less effected. I don't know maybe it's my own bias but I have the feeling intelligent life is not as common or as rare as people believe. As we look into the sky we are seeing the past and even in our own galaxy we can be looking as much as 100,000 years in the past.

  • Frank White
    Frank White   1 weeks ago

    One variable not in the "equation": What do you see when you OPEN YOUR EYES?

  • Boris Chang
    Boris Chang   1 weeks ago

    The universe might be teeming with life, even intelligent life. But the odds of meeting up with intelligent life in another star system are probably close to nil due to the propensity for intelligent life (judging by intelligent life on earth) of destroying the planet’s ability to sustain life due to over-exploitation of resources, destruction of the environment, and overpopulation. That happening before they are able to achieve interstellar travel seems a plausible outcome.

  • qcxcq
    qcxcq   1 weeks ago

    Great in-depth explanation of the power of Bayesian statistics. But something that makes me skeptical about the odds as a whole is that the very quick appearance of life on Earth is always interpreted as life being common in the universe. Is there a reason why it's unlikely that for example it might have required the entire lifetime of a very specific generation 2 solar system to develop life to become capable of 'panspermically' seeding the early Earth?

  • Joel Kavanagh
    Joel Kavanagh   1 weeks ago

    owl th' wary beast dis-semanates it's stadard comment :: ' where is s. Lem with his '60s ' silent universe,, itsense of impropab. of 'Contact ", still holding up! " ? ... ( all the best from Berlin ... .. .

  • KikodeKliko
    KikodeKliko   1 weeks ago

    I don't get the whole statistic conclusion at all (why is life common and intelligence rare instead of both rare?) But I appreciate knowing that a scientist did the math and came to this conclusion :-)

  • Martyn Knipe
    Martyn Knipe   1 weeks ago

    Interesting to listen to another reasonable and possibly true theory.But with over half the world population believing in UFO´s many of which defy any known characteristics of earthly propulsion and with so many creditable witnesses observing this , I find it hard not to believe that other intelligent races do not exist.Our science says (at the moment) and Einstein said ,travel faster than the speed of light is not possible, but the planet next door never heard of the guy and perhaps came up with different theories about space travel.Personally I think the universe is teeming with life and to date have witnessed two unexplained sightings myself.

  • Nelson Mandela Muntz
    Nelson Mandela Muntz   1 weeks ago

    No we’re not we’re surrounded by billions of other weirdos and misfits not including all the creatures that wanna kill us for food don’t need another bunch of psycho’s looking to take us out, 🤣🤣🤣 life’s a horror show get used to it 🤣🤣🤣🤣

  • B Williams
    B Williams   2 weeks ago

    The two scariest thoughts everA) We are alone in the universe B) We are not alone in the universe

  • Bob Fisk
    Bob Fisk   2 weeks ago

    A fallacy of all this is the assumption that humans are intelligent. Oopsie.

  • GODLESS101
    GODLESS101   2 weeks ago

    Everything that can happen within the universe does . . . And happens . . . And happens again billions and billions and billions of times over. Astoundingly rare events happen all the time. Speculating that our existence might be a singularly rare event within the universe without first explaining how that could even be possible seems more like faith and arrogance, after all, whatever is the reason for that must itself be an extremely unlikely event that needs explanation.

  • Bobby Moncrief
    Bobby Moncrief   2 weeks ago

    Every time I watch this, I understand a little bit more.

  • Bryan B
    Bryan B   2 weeks ago

    It is ridiculous to say intelligent life took billions of years to evolve on earth and therefore suggest that intelligence in the universe is rare. The dinosaurs were wiped out 65 million years ago. 65 million years is how long it took intelligent life to evolve not billions.

  • DBAY 012
    DBAY 012   2 weeks ago

    The Universe is so huge that, even if there are other intelligent species, until we develop space craft that has warp drive capabilities able to reach the speed of light , we’ll never come across them.

  • Rick Rhone
    Rick Rhone   2 weeks ago

    whats up with the green square at 17:09

  • rcud1
    rcud1   2 weeks ago

    Yes. For all practical purposes, we are alone!

  • MadMax McInnes
    MadMax McInnes   2 weeks ago

    We're most certainly not alone ........ the size of the universe is unfathomably huge ...... but I reckon, because of that, we're never gonna' make contact with any life. Mankind simply won't be around long-enough to achieve the technology to enable that to happen.

  • Marianela Guzman
    Marianela Guzman   3 weeks ago

    Did not expect this video to be so wholesome! 😂 We do have to make many assumptions just to get to any hypothesis, thinking of "human intelligence" as point of comparison when this concept can be something else, intelligence for an alien organism could be something we can't even imagine. But that's a completely different topic. Truly fascinating. Thank you for sharing your thoughts and knowledge with us.

  • Jon Shaffer
    Jon Shaffer   3 weeks ago

    You really need to take better care of yourself and waking up and taking a shower before you get from a camera

  • Todd F Wright
    Todd F Wright   3 weeks ago

    I'm still waiting for someone to recognize the first essential question that must be answered before going any further, and I'm frankly baffled that not one person has yet done this.The question is: WHAT NUMBER of specific factors, combined in all the right ways, at the right time, are actually necessary for abiogenesis to occur? All the evidence so far seems to indicate that it may be such a huge number that only one instance of abiogenesis could happen, and that is Earth. (Yes, this is essentially what the Rare Earth Hypothesis is, but I am suggesting even that hypothesis has not gone far enough in considering the necessary elements required.) What if it is so unlikely, that it actually requires an infinitely large universe to make it mathematically possible at all? If that's the case, then we can be certain of the answer and no further energy need be wasted with pursuing the question.Yet, no one has even asked the question, and there is no point whatsoever in attempting to continue making opinion (fantasy)-based guesses or guesses based on the method you demonstrate here. It may be that we are simply incapable of even estimating the number of factors necessary for abiogenesis to occur, and it is easy enough to prove this true by stating one undeniable fact: We have never learned how to create life.If WE can't create biogenesis ourselves, with all of our knowledge of science, then how dare we even go on without accepting the reality of not actually knowing the number of special factors necessary?

  • Darth News
    Darth News   3 weeks ago

    Bruh. This dude has a chin large enough to sink the titanic

  • Darth News
    Darth News   3 weeks ago

    Faith is all we have man. Nothing is set in stone

  • Kahanu Morales
    Kahanu Morales   3 weeks ago

    Can't wait to rewatch this when I'm not half asleep

  • matthew owens
    matthew owens   3 weeks ago

    When you look up at the stars and think maybe there is someone or something on one of thoes stars doing the same

  • RUHI4
    RUHI4   3 weeks ago

    Consider this:"The learned men, that have fixed at several thousand years the life of this earth, have failed, throughout the long period of their observation, to consider either the number or the age of the other planets. Consider, moreover, the manifold divergencies that have resulted from the theories propounded by these men. Know thou that every fixed star hath its own planets, and every planet its own creatures, whose number no man can compute." – "Gleanings from the Writings of Baha’u’llah", p. 163.

  • Screww Googlle
    Screww Googlle   3 weeks ago

    Bottom Line = Math-a-Magicians have always been Full of Schitt !

  • Screww Googlle
    Screww Googlle   3 weeks ago

    Pretty Poor example when you open your video Questioning a Fake Phony POS like Bill Nye "The Sciece Guy" who isn't even a Scientist !

  • Boris
    Boris   3 weeks ago

    We are not alone... the aliens are just avoiding a bad neighborhood

  • Hebe Gebes
    Hebe Gebes   3 weeks ago

    life out there? to this i say no.