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 • 1 258

  • peter papadimitriou
    peter papadimitriou  20 hours 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 days back

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

      • Greg Zeng
        Greg Zeng  1 days 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  5 days back

          blessed are the meek

          • DC S
            DC S  7 days back

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

            • Jeremy Poedel
              Jeremy Poedel  1 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.

              • Ákos Körmendi
                Ákos Körmendi  4 days 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  4 days back

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

            • Martin Gleeson
              Martin Gleeson  1 weeks back

              Micro evolution Yes macro evolution No

              • Freedom Anderson
                Freedom Anderson  4 days back

                Speciation has been observed.

              • Hm Grraarrpffrzz
                Hm Grraarrpffrzz  4 days 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  3 weeks back

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

              • Matt Morgs
                Matt Morgs  3 weeks back

                What about sexual selection my guys ?

                • Neale Baxter
                  Neale Baxter  3 weeks 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  4 weeks 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  3 weeks back

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

              • fivedriedgramsinsilence

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

              • Scott DeGasperis
                Scott DeGasperis  4 weeks 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  4 weeks 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  1 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  3 weeks back

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

                                  • Neale Baxter
                                    Neale Baxter  1 months back

                                    … and we'll all think for you.

                                  • Joel M
                                    Joel M  1 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  3 weeks 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  4 weeks back

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

                                                  • Demiligne
                                                    Demiligne  4 weeks 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  2 months back

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

                                                    • miri
                                                      miri  2 months back

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

                                                      • James Benton Ticer
                                                        James Benton Ticer  2 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  2 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  2 months back

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

                                                        • tigerfan3905
                                                          tigerfan3905  3 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  3 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  3 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  3 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  3 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  2 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.

                                                                • Tessa T
                                                                  Tessa T  3 months back

                                                                  I've been to see the new Smithsonian Exhibit! My son and I met friends their earlier this month. It was really cool! I'd like to go back after the school year starts when we have more time and it is less crowded.

                                                                  • Richard Deese
                                                                    Richard Deese  3 months back

                                                                    EDICT = *_Evolution: Diversifying into Infinite Combinations (Theoretically)._* :o) Thank you! 𝓡𝓲𝓴𝓴𝓲 𝓣𝓲𝓴𝓴𝓲.

                                                                    • Iván
                                                                      Iván  3 months back

                                                                      Gotta love Biology. 😏

                                                                      • Quinceps
                                                                        Quinceps  3 months back

                                                                        Just say "land" for me (La La Leeeeend).