How Evolution Works (And How We Figured It Out)

  • Published: 12 June 2019
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    As a scientific concept, evolution was revolutionary when it was first introduced. With the help of all three of our hosts and the Smithsonian National Museum of Natural History’s new Deep Time Hall, we’ll try to explain how evolution actually works and how we came to understand it.

    This episode was written by Darcy Shapiro.

    Produced in collaboration with PBS Digital Studios:

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    Bowler, P. (2001). History of Evolutionary Ideas: The Modern Synthesis. ELS: Encyclopedia of the life sciences, 1-5.
    Papavero, N., & Santos, C. F. M. D. (2014). Darwinian evolutionism? Contributions of Alfred Russel Wallace to the theory of evolution. Revista Brasileira de História, 34(67), 159-180.
  • Science and Technology Science and Technology

Comments • 1 283

  • Aydin Barnbrook
    Aydin Barnbrook  4 days back

    Christians should watch this stuff. At this point I think people who have access to the internet are just like ignoring facts. This is better than going to church. Make this explode pls.

    • Aydin Barnbrook
      Aydin Barnbrook  4 days back

      @picturepainterreligion bothers me

    • picturepainter
      picturepainter  4 days back

      Most Christians accept evolution. The mainstream ones at least.

  • service asap
    service asap  5 days back

    How does evolution explain identical twins with different DNA and different fingerprints?...

    • service asap
      service asap  2 hours back

      @Ákos Körmendi Logic? according to atheism the concept of logic can't be proven scientifically so all you're saying with all your rambling is that atheist have "Faith"

    • Ákos Körmendi
      Ákos Körmendi  2 hours back

      @service asap Nope, It's the only logical conclusion. Unfortunately, we can't peer back into hundreds of millions of years to see what exactly happened. However, we can use reason, logic, our knowladge of the theory of evolution and of living organsisms to figure out what most likely happened. We don't have direct evidence, which kinda suks tbh. But we can still infer from other places to answer the question.

    • service asap
      service asap  2 hours back

      @Ákos Körmendi No you go with that because you've produced no evidence to support your hypothesis...

    • Ákos Körmendi
      Ákos Körmendi  3 hours back

      @service asap No. Our common ancestor with them already would have male and female. Convergent evolution on such a scale is incredibly unlikely, while not out of the realms of possibility, but the probability of our common ancestor already having this trait is million times more likely, so we're going with that.

    • service asap
      service asap  3 hours back

      @Ákos Körmendi Sooooo humans plus all the creatures on this planet just happen to evolve male and female all at the same time sounds like evolution was intentional...

  • Wichita Disciple
    Wichita Disciple  6 days back

    “The extreme rarity of transitional forms in the fossil record persists as the trade secret of paleontology. The evolutionary trees that adorn our text- books have data only at the tips and nodes of their branches; the rest is inference, however reasonable, not the evidence of fossils.""
    -Stephen Gould

    • Hamma Lammadingdong
      Hamma Lammadingdong  3 days back

      Google “list of transitional fossils” and enjoy...

    • picturepainter
      picturepainter  4 days back

      Stephen Jay Gould preferred to think of evolution as a messy bush rather than a tree.

  • Fracking Saves
    Fracking Saves  6 days back

    David Koch: a horrendous & evil billionaire whose name should not be associated with any scientific endeavor.

    • peter papadimitriou
      peter papadimitriou  1 weeks back

      Great video I like to find out more the problem that I have a disability I'm a stroke and cardiac arrest survivor just to clarify and the one stupid question I have is if living things change over time including us humans, how come the change doesn't go from having one thing and the next generation its something else?

      • Reviews You Can Use
        Reviews You Can Use  1 weeks back

        If evolution are true, Is there a discovery of specie today that being evolb to new specie?

        • Greg Zeng
          Greg Zeng  1 weeks back

          A very brief version of evolution.
          Other variables are much more important than TIME.
          If the breeding cycle is very short, then TIME is less required.
          Many "tricks" can be used to shorten the breeding cycle. Correct selection of species. Acting genetically, environmentaly, etc - simultaneously & sequentially. Increasing "randomness" via radiation, chemicals, etc.
          In my forthcoming book: "Non-human Cognitive Science", I show how cache systems (software) can use hardware to create "evolution". This evolution video does not show that evolution is software. Hardware (biochemistry here) comes in many forms, but it does not create evolution.

          • son of perdition
            son of perdition  2 weeks back

            blessed are the meek

            • DC S
              DC S  2 weeks back

              "...if you say that you can't say it. Does it mean you trip over the words"?

              • Jeremy Poedel
                Jeremy Poedel  2 weeks back

                Something can’t come from nothing. Matter cannot make itself. There is no examples of change of kind. The birds adapted but they always remained birds. There is no fossil examples of the transitions actually happening. A bird is a bird is a bird. It’s not evolution, it’s adaptation. Of course life is always changing, the earth changes. If you are telling me that all life arose from the sea, how did gills magically become lungs? How long did that take? There are fish today that have four flippers, they did not evolve into legs. What really gets me is the absolute certainty of these ideas and claiming to be strictly scientific when no evidence of the beginning or change if kind can actually be provided. DNA is the book of like that was designed. It is not just by accident.

                • Hamma Lammadingdong
                  Hamma Lammadingdong  3 days back

                  Jeremy Poedel - here’s a little live letter from the National Academy of Sciences...

                  “...the theory of evolution is supported by so many observations and confirming experiments that scientists are confident that the basic components of the theory will not be overturned by new evidence.”

                • Ákos Körmendi
                  Ákos Körmendi  2 weeks back

                  Demonstrate something cannot come from nothing.
                  Demonstrate matter cannot make itself.
                  I'm not arguing for either of these, I don't find them reasonable either, but you have no basis to say that they are impossible to happen beside not seeing it happen yet. And none of it has to do with evolution.
                  Correct, kinds always remain. Birds are still birds. Just like how mammals are still mammals. Birds are still dinosaurs, and humans are still apes. Our ancestry will never change.
                  Adaptation is evolution.
                  The gills didn't become lungs, blabbers, the thing that keeps fish afloat probably did, seeing how they are found in the same place with the same structure.
                  Of course there aren't, they already went extinct as they were probably outcompeted in mobility by tetrapods. Tiktaalik tho is a fossil fish who possesses 4 flippers.
                  There's no absolute certainity in science, these are all conclusions drawn from evidence and knowladge. Anyone saying with absolute certainity that evolution happened is foolish, just like how anyone who says with absolute certainity that there are anything is foolish. You can't know everything, you can't rule out the possibility that you are hallucinating. There can only be reasonable certainity.
                  DNA is a sequence/molecule for coding proteins and their order. Not a book. You can't actually tell what a sequence does by looking at it. If you could, scientists wouldn't be cautious with gene modification, as they don't know what side effects might result from it. It's not something you can read, you need the entire reproduction system to its thing for it to make sense.

                • Hm Grraarrpffrzz
                  Hm Grraarrpffrzz  2 weeks back

                  For how many million years have you watched birds, so that you can say that they were always birds?

              • Martin Gleeson
                Martin Gleeson  2 weeks back

                Micro evolution Yes macro evolution No

                • Freedom Anderson
                  Freedom Anderson  2 weeks back

                  Speciation has been observed.

                • Hm Grraarrpffrzz
                  Hm Grraarrpffrzz  2 weeks back

                  both is exactly the same thing, only looked at with different timeframes in mind. saying that one works and the other not is ignorant

              • Taran O'Reilly
                Taran O'Reilly  4 weeks back

                I think this is one of your best videos. Too bad it hasn't been viewed more.

                • Matt Morgs
                  Matt Morgs  1 months back

                  What about sexual selection my guys ?

                  • Neale Baxter
                    Neale Baxter  1 months back

                    I'm not getting any selection.
                    It's been ages since I've had my brains "selected" out.
                    To paraphrase Mick Jagger, _'I can't get me no, No, no selection'_

                • r4hnsn
                  r4hnsn  1 months back

                  Its a miracle !! my eyes just decided to grow, even though I was just a sightless blimp, and then somehow my pea brain also thought it better connect up some wiring to go with them.

                  • Neale Baxter
                    Neale Baxter  1 months back

                    Nope! Don't think your pea brain ever did connect up some wiring.

                • fivedriedgramsinsilence
                  fivedriedgramsinsilence  1 months back

                  There is no such thing as "macro and micro evolution'', just evolution.

                • Scott DeGasperis
                  Scott DeGasperis  1 months back

                  “Nothing in biology makes sense except in the light of evolution.”
                  ― Theodosius Dobzhansky

                  • David McCaig
                    David McCaig  1 months back

                    Man just observes what had already been set in motion and therefore deserves no credit for the genius of what he observes.

                    • Deecy P
                      Deecy P  1 months back

                      Don’t we already know

                      • Nate
                        Nate  1 months back

                        Becoming quite addicted to this channel and having a decent understanding of both science and english while being a native french speaker I'm starting to seriously consider adding french subtitles on these videos. Though I've never done anything like that I'm sure I could figure it out.

                        • Neale Baxter
                          Neale Baxter  1 months back

                          Mon français est de la merde. Votre anglais est bien meilleur.

                      • Sophia Sourkraut
                        Sophia Sourkraut  1 months back

                        I wanna watch When Whales Walked, but it's not available outside the U.s. :(

                        • Tamara Molina
                          Tamara Molina  1 months back

                          Fantastic summary with awesome attention to oft-forgotten scientists in the history of the evolution of evolution theory!

                          • Gregory Munby
                            Gregory Munby  1 months back

                            EXCELLENT VIDEO!!

                            • Eternal - Fire
                              Eternal - Fire  1 months back

                              I went to the smithsonian on my school trip to Washington but it was still in renovation.

                              • Sophie Shenkal
                                Sophie Shenkal  1 months back

                                This is my favorite channel on YouTube. Thank you for existing so that I can learn about all of these incredible things 🙏🙌

                                • Joel M
                                  Joel M  2 months back

                                  Please send this video to ray comfort and every other nutbag that does not think evolution is true!!!

                                  • Soldier Of Life
                                    Soldier Of Life  2 months back

                                    I'll pray for yall

                                    • James West
                                      James West  4 weeks back

                                      Soldier Of Life
                                      I'll sacrifice a goat for y'all.

                                    • Neale Baxter
                                      Neale Baxter  2 months back

                                      … and we'll all think for you.

                                    • Joel M
                                      Joel M  2 months back

                                      Soldier Of Life Please don’t , it doesn’t work anyway!!!

                                  • Plack morty
                                    Plack morty  2 months back

                                    The evolutionary tale of evolutionary theory

                                    • The FPV Life
                                      The FPV Life  2 months back

                                      Meteor strikes has a lot to with our evolution. It altered and allowed we humans to evolve.

                                      • Andy Miron
                                        Andy Miron  2 months back

                                        And we still evolve. Humans get larger och taller all the time..
                                        Eat that you religions nuts. :D

                                        • anti/HUMAN Designs
                                          anti/HUMAN Designs  1 months back

                                          @Cory in da hus Yes, and better overall health/sanitation. We are less sick, and better fed (both amount and quality of food), so we develop better.

                                          Our average height has gone up a lot over just a few thousand years, yet our DNA hasn't really changed in taht short time, so this particular thing has nothing to do with evolution, just as you say.

                                        • Cory in da hus
                                          Cory in da hus  2 months back

                                          Thats due to better nutrition

                                      • Dicky Liu
                                        Dicky Liu  2 months back

                                        I thought evolution was invented by Pokemons...

                                      • LegoCookieDoggie
                                        LegoCookieDoggie  2 months back

                                        um so why would the Koch brothers be okay with the theory of evolution and "that there are limited resources" and then proceed to destroy our planet?

                                      • George Mulvaney
                                        George Mulvaney  2 months back

                                        You left out von Humbolt. Darwin specifically mentioned him.

                                        • Alopias pelagicus
                                          Alopias pelagicus  2 months back

                                          I literally just had to like the video immediately after they included Wallace. Thank you!
                                          However, Darwins theory was actually based on the Mockingbirds. Only later did the finches play a role.

                                          • Paul Ford
                                            Paul Ford  2 months back

                                            I've been to that museum several time - it's an amazing place. I could spend days looking at all the exhibits! Thanks for this video. 😊

                                            • Edward Martens
                                              Edward Martens  2 months back

                                              Really Nice to see three of the great presentors of this channel explaining it so clearly and enthusiasticly.

                                              • Harry Decker
                                                Harry Decker  2 months back

                                                Darwin only mentioned finches three times in Origin of Species. Many other birds are mentioned such as pigeon (106 times), duck (42 times), goose (23 times), and woodpecker (16 times). The word beak and various forms are mentioned over 70 times, and Darwin does write about differences in beaks, uses of beaks, beak size, and beak shape among many different birds. Here is the only thing he wrote about the finch and beaks: “The short-faced tumbler has a beak in outline almost like that of a finch.”

                                                • Strength Honour
                                                  Strength Honour  2 months back

                                                  I like the camera used to record the clips of this video in the museum. It looks so clear.

                                                  • Dion7
                                                    Dion7  2 months back

                                                    Koala's have proven that survival of the fittest is nonsense.

                                                    • Dion7
                                                      Dion7  1 months back

                                                      @Demiligne Right, that's the Dutch spelling. Force of habit.

                                                    • Demiligne
                                                      Demiligne  1 months back

                                                      + *Dion7* There's no apostrophe in "koalas".

                                                    • Zanta 100
                                                      Zanta 100  2 months back

                                                      sloths do that waaaaayy better
                                                      they are so lazy they can die from gripping their arm

                                                    • Dion7
                                                      Dion7  2 months back

                                                      @Ricahrd P'Brien XD

                                                    • Ricahrd P'Brien
                                                      Ricahrd P'Brien  2 months back

                                                      You are a better example.

                                                  • William Bailey
                                                    William Bailey  2 months back

                                                    Are you people not aware that you're spuiking an exhibition which seeks to rehabilitate of one of the most insidious, influential climate change deniers in history? A man uniquely responsible for promoting ecocide, poverty, death and destruction on an unimaginable scale?
                                                    David Koch was no friend either to humanity or science, and I don't know how much the Smithsonian paid you for this but you should've refused to promote anything bearing his name as a matter of principle.

                                                    • Socra Tease
                                                      Socra Tease  3 months back

                                                      Guy with glasses is best. Can understand him and he’s easiest on ears

                                                      • miri
                                                        miri  3 months back

                                                        We evolved and that’s the end of the never ending story

                                                        • James Benton Ticer
                                                          James Benton Ticer  3 months back

                                                          Told many a Christian to watch this...guess how many have? yup zero.

                                                          • Paul Ford
                                                            Paul Ford  2 months back

                                                            Now now, many (if not most) Christians accept the facts of science, including evolution. It's the vocal know-nothings that make the most noise though.

                                                          • miri
                                                            miri  3 months back

                                                            James Benton Ticer
                                                            Even if they did do you think they’d see reason? Maybe eventually but they tend to persist in their ignorance even in the face of evidence. That is why it’s called faith I guess.

                                                        • tigerfan3905
                                                          tigerfan3905  3 months back

                                                          What's going on with stories of soft tissue and blood vessels being found in dinosaur bones??

                                                          • tigerfan3905
                                                            tigerfan3905  4 weeks back

                                                            @anti/HUMAN Designs It's a mystery dude...just like what caused the big bang, the fine tuning, the 3.5 billion bits of code in dna, what 96% of the universe consists of, the cambrian explosion, no precursors to the dinosaurs, how the big bang produced laws, forces, space/time...etc. Our science is a joke!! Happy now??

                                                          • anti/HUMAN Designs
                                                            anti/HUMAN Designs  4 weeks back

                                                            @tigerfan3905 I'm not really happy with that.

                                                            I mean, this was a T-Rex, right? Correct me if I remember wrong. That means they found the fossil in the upper cretacious rock, otherwise that would be even bigger news.
                                                            Creatacious rock is 66+ million years old.
                                                            T-Rex's only lived the last 3 million years before the K/Pg extinction event, 66 million years ago.

                                                            You say the bone must be at maximum 3-4 million years old, yet that would disagree with all fields of science that's involved, here. Creatacious rock cannot be that young, not only befcause it would mean that you would have to fit the entire paleogene in only 4 million years, which isn't reasonably possible, but for a arge number of other reasons.

                                                            No, the fact is that while I agree that fossilization happens over only a few million years, give or take, I'm also awware that things can be preseved in a number of ways, such as by being encased in amber.
                                                            This fact proves taht there is no absolute law that states it's impossible for this to survive past 4 million years.

                                                            So, the choice is to either go against all the related fields of scinece, and all the facts and measurement, or alternatively to accept that we just found yet another way that something can be preserved for a longer time.
                                                            Which is the most reasonable, to you?

                                                          • tigerfan3905
                                                            tigerfan3905  4 weeks back

                                                            @anti/HUMAN Designs Oh well, agree to disagree I guess. It won't fix any of the worlds problems either way...✌✌✌

                                                          • anti/HUMAN Designs
                                                            anti/HUMAN Designs  4 weeks back

                                                            @tigerfan3905 Except it's clearly possible, since it did survive that long.

                                                            Science moves on, it learns something new. Apparently there are cases where it can be preserved that way, that's what we learnt.
                                                            Yes, the increase in entropy and so on, but once something has been encased in a crystal, for example, then entropy can stay relatively the same for a very, very long time.
                                                            I mean, we have insects from the age of the dinosaurs encased in amber, and they're pretty well preserved. And what we're talking about here is merely some remains of soft tissue from inside a bone.
                                                            Like I said, it wasn't soft tissue when they found it, they needed to apply a solution to remove the minerals from it, and then it because fairly soft. That doens't mean it's "well preserved" in any way, it's just a softer material.
                                                            It souds like you think you can transplant it into a living creature and it would work fine. It's completely broken. The only interesting thing about it is that it wasn't replaced completely by minerals, that's all. You're making a chicken out of a feather, here.

                                                          • tigerfan3905
                                                            tigerfan3905  4 weeks back

                                                            @anti/HUMAN Designs 3-4 million is the oldest, the best case scenario of preservation could possibly do. It's impossible for tissue to survive 65 million years.

                                                        • Roy Calderon
                                                          Roy Calderon  3 months back

                                                          Now this is beautiful!. Love this video!!! Thank you for this.

                                                          • Leto85
                                                            Leto85  3 months back

                                                            It's kinda funny now I think of it; this video is basically the evolution of evolution.
                                                            I'm afraid that this wonderful hall of wondrous is located a few oceans too far for me, but maybe they'll make a 3D tour one day? I'm definitely interested. :)

                                                            • Dan Severns
                                                              Dan Severns  3 months back

                                                              This is such an excellent video but the "music" detracts from it. It would be better with no music.

                                                              • Valeria Hidalgo Ruz
                                                                Valeria Hidalgo Ruz  3 months back

                                                                I love u guys! Such a great channel <3 Greetings from Chile

                                                                • clifton gaither
                                                                  clifton gaither  3 months back

                                                                  Kelly , you are absolutely adorable.