The Evolution of the Heart (A Love Story)

  • Published: 14 February 2019
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    In order to understand where hearts came from, we have to go back to the earliest common ancestor of everything that has a heart. It took hundreds of millions of years, and countless different iterations of the same basic structure to lead to the heart that you have today.

    Thanks as always to Nobu Tamura for allowing us to use his wonderful paleoart:

    Thanks to Ceri Thomas for the Ichthyostega reconstruction. Check out more of Ceri's paleoart at and

    Produced in collaboration with PBS Digital Studios:

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Comments • 613

  • brooklyn560
    brooklyn560  3 hours back

    A half billion years of evolution, just for us to clog it with red meat cheese and fried food

    • Fabricio Fercher
      Fabricio Fercher  1 days back

      Emotions are in the brain, not the heart. This mythological notions are not science!

      • Bob Bowles
        Bob Bowles  3 days back

        I just noticed the date this was uploaded - day before Valentine's!

        • Fadil Langston
          Fadil Langston  2 weeks back

          What about the evolution of spooky, scary skeletons?

          • Nate
            Nate  1 months back

            It's not the first video on PBS Eons where I notice this but I must say I find it really good that he talks of a "healthy debate" among researchers. He acknowledges that there are currently different opinions on the matter without any drama. Disagreeing about something and debating about it can lead to better understanding. It allows people to think in more than one way about the evidence we have and THIS to me is the heart (pun fully intended) of the scientific process. It's a good thing.

            • TOZTYBUNZ
              TOZTYBUNZ  1 months back

              Sorry but I heard stinks 0:39

              • arno kosterman
                arno kosterman  1 months back

                A ant runs vaster in constant motion.
                than Lepra😍 if we look from tham in there own dimentions towarts it's inviormant.

                To underatand howe the hart wurks in its own manivistation you need tu understand the proton😍

                Nice ro see the diverences of harts.

                Is in a dolfin is tha hart point open🙄?
                I wish to understand.
                In mi excperience if the hart point is open we have fins in stade of lagges🙄
                This i wish to find in the knowledge if it is like that😍 so i can share it en go more in to the depts of it
                From the atomig plasmatic behaviure towats a grown entety
                I have seen the manivistation of mi self 80 % just from understanding the atom the way it is shared in plasma science😍

                • arno kosterman
                  arno kosterman  1 months back

                  Just read it as it is intent to 😍
                  Withs wurth you dont understand when u have read the wole sentens our text i wil tace the time to explain😍

                • Blu
                  Blu  1 months back

                  @arno kosterman Dude I love your comment and all but I can barely understand what you're saying cause the spelling is so bad.

                • arno kosterman
                  arno kosterman  1 months back

                  Men have shift there shacra treu the wish to the wish towart evolution within there own speces
                  En that is way our hard is this way

                  I think that picturs of human hart develpmend don' sheuths realety.
                  As the cell blast has let men loos the treu immige of there own creation to follow🙄

                  Is the tinman tisheu containing
                  Amino structure of thin?
                  in the eurtly inviormant has add to .
                  But the feilds were there furst to atrect en manivest.
                  Feilds from the intentions of the colective entetys there souls 😍🙄

                  I go surge for the tinman tisheu wat it excactly is thank you🍀🌹

                  For enteties to start wurking en evolving with surtent needs.
                  En jat it has manivested this needs on its own to be able to survive🐳🐸🕊

              • Todd Mitchell Christensen

                I'd really like some more anatomy evolution videos. Why do we have lips? Why do some animals have beaks? When did muscles first appear? Why don't we have claws?

                • Bryan lozano leon
                  Bryan lozano leon  1 months back

                  All these million of years my Heart took to create itself and develop... For her to come and destroy it 😢

                  • Salvatore Escoti
                    Salvatore Escoti  2 months back

                    It is a very flawed design. Multiple small hearts all over the body would be much more failsafe. It is strange that mammals have two kidneys if one would do the job perfectly by its own. But we have only one heart even if multiple hearts would be much better. So much for INTELLIGENT DESIGN!!

                    • Hot Key
                      Hot Key  2 months back

                      How about the evolution of the pancreas?

                      • River Loves Musicals
                        River Loves Musicals  2 months back

                        Love the video. But how do you make a video on the evolution of hearts without talking about the amazing complexity of crocodile hearts???

                        • shadowblobSS
                          shadowblobSS  2 months back

                          What I gathered from this video, scientists must have great eyes, cause I can't see any heart in a fossil.

                          • Dea Likes Bands
                            Dea Likes Bands  3 months back

                            Playback speed .75

                            • Sachin Rao
                              Sachin Rao  3 months back

                              Could you do a video on the evolution of the brain?
                              And, I really admire your work. It's a beautiful learning experience. Thank you.

                              • Chris Metcalf
                                Chris Metcalf  3 months back

                                The fact that a vertibrate heart develops the same way - I mean come on, if you have any doubts about evolution, explain that.

                                • martijns ark15
                                  martijns ark15  3 months back


                                  • Richard Deese
                                    Richard Deese  3 months back

                                    Thanks! I do have one minor complaint [I know, I'm sorry ;) ]. I think this video would have been even more entertaining / informative, if you had included some numbers regarding when oxygen became a thing, when multicellular life started using it widely, and tracking the evolution of the heart along with the rise in atmospheric oxygen. Just trying to help! ;) Rikki Tikki.

                                    • One Nation Under God
                                      One Nation Under God  3 months back

                                      Amazing that our heart is so developed after just 35 days from conception. Such a shame some people believe abortions should be allowed clear up to birth.

                                      • x64Joxer
                                        x64Joxer  3 months back

                                        thank you

                                        • SSFandomLove
                                          SSFandomLove  3 months back

                                          I love this channel but every time I watch this guy’s video I keep getting distracted by his non-stop hips thrusts 🤣
                                          I would keep wondering why he’s doing that and then I would keep missing segments of the video lol
                                          (By the way I absolutely do not mean getting distracted “that way” 😅)

                                          • 1of3
                                            1of3  3 months back

                                            Very informative. Maybe do that for other organs/problems like kidneys or waste disposal

                                            • Bethany Linebarger
                                              Bethany Linebarger  4 months back

                                              I am still waiting on the episode covering the evolution of a the placenta that gave rise to live birth being a "thing." Did I just miss it?

                                              • S
                                                S  4 months back

                                                Can you also do a video on Bioluminescence that must have also existed countless times in our past and not use exist in today’s time. The ocean must have had it back then numerous times for example.

                                                • S
                                                  S  4 months back

                                                  Can you do a video on the evolution of bone to mobility for sea, land, and sky creatures... and some of its return to the previously mentioned niches.

                                                  • nil bogg
                                                    nil bogg  5 months back

                                                    I would like to see the "Evolution of the BRAIN". It is after all, the most important organ. It MUST be well researched...right?

                                                    • Aishwarya Singh
                                                      Aishwarya Singh  5 months back

                                                      Can you please do a video on the possibility of immortality in multi-cellular organisms!!

                                                      • Buddha's Disciple
                                                        Buddha's Disciple  5 months back

                                                        Evolution of lungs / respiratory system next please :)

                                                        • Joseph Banatlao
                                                          Joseph Banatlao  5 months back

                                                          Wait, you mean it didn't came from Kingdom hearts?!

                                                          • Tyler Merlin
                                                            Tyler Merlin  5 months back

                                                            A wealth of information explained extremely well. Thanks.

                                                            • Teacup Toe
                                                              Teacup Toe  5 months back

                                                              Can you tell the story of gums? It's weird having pink squishy stuff around our teeth like that

                                                              • sollidottingen
                                                                sollidottingen  5 months back

                                                                I'm pretty sure people also say they'll give the D to someone.. Or the finger.

                                                                • Thomas Just
                                                                  Thomas Just  5 months back

                                                                  Music was unnesesary, romanticism was also not nesesary...It bored me and I lost interest...thumbs down

                                                                  • The Kiss off
                                                                    The Kiss off  5 months back

                                                                    ITs More Than That!!

                                                                    • Bagville Babacar
                                                                      Bagville Babacar  5 months back

                                                                      Good video. I have a question though. Of course creatures with hearts have DNA that makes hearts, but I don't get the reason that means these creatures are related. I think the video mentions that different creatures developed hearts separately too. So, the 'tinman' genes in flies just 'look like' the genes that make the human heart in people, what does that mean? That must be overly simplified because obviously the human heart is significantly different, which to me (a simple layperson) the human DNA should have significantly more and different instructions to build the human heart. Is that right? So in what way are the genes related? Why does that mean they related?

                                                                      • Ironweaver
                                                                        Ironweaver  5 months back

                                                                        In which we learn that time lords are descended from squid.

                                                                        • Space dolphin corp.
                                                                          Space dolphin corp.  5 months back

                                                                          Went to the google science journal.
                                                                          I didnt know Google was so much more awesome than id ever expect. THATS THE REASON WE ALL NEED GOOGLE FI.
                                                                          Thanks PBS-eons your videos bring my childhood dreams into reality

                                                                          • Perry Dowd
                                                                            Perry Dowd  6 months back

                                                                            Once I loved
                                                                            And it was a gas
                                                                            Soon turned out...

                                                                            • Jude Francisco
                                                                              Jude Francisco  6 months back

                                                                              I'm in love to the host of this episode. :)

                                                                              • MK B
                                                                                MK B  6 months back

                                                                                "Like every other part of you, your heart is as complex as the story behind it. So the next time you give your heart away to someone, be sure that they know that your give is more than a half billion years in the making."

                                                                                Wow thanks

                                                                                • Robert Huston
                                                                                  Robert Huston  6 months back

                                                                                  Nice. Very helpful. Thanks a zillion Universe.

                                                                                  • shafeen Mahmud
                                                                                    shafeen Mahmud  6 months back


                                                                                    • Dalia Capellan
                                                                                      Dalia Capellan  6 months back

                                                                                      Yes, but how do you fix it once it's been broken?

                                                                                      • Yathish s
                                                                                        Yathish s  6 months back

                                                                                        It is interesting to know that the same concepts (features) appears separately, multiple times... It's like life knows what's best for life to thrive.. and there is more than one way to do it....
                                                                                        I would really like you to make a video of an overview of the evolutionary path.. the journey life took to get here...
                                                                                        Like the different features that came and went and a few were useful so it stayed...
                                                                                        It would actually turn out to be a story of life's features their birth, evolution, and extinction...

                                                                                        • Joel Bernal-Garcia
                                                                                          Joel Bernal-Garcia  7 months back

                                                                                          thanks for getting to the...heart of issue

                                                                                          • Nikki Bishop
                                                                                            Nikki Bishop  7 months back

                                                                                            I always want more about invertebrates (from any eon!)

                                                                                            • Nikki Bishop
                                                                                              Nikki Bishop  7 months back

                                                                                              Octopodes - yay!

                                                                                              • Fadimations
                                                                                                Fadimations  7 months back

                                                                                                What about your kidneys. You can give them to people and if you lose both or they break you can die