How Blood Evolved (Many Times)

  • Published on: 15 January 2019
  • Blood is one of the most revolutionary features in our evolutionary history. Over hundreds of millions of years, the way in which blood does its job has changed over and over again. As a result, we animals have our familiar red blood. But also blue blood. And purple, and green, and even white.

    Thanks to Julio Lacerda, Lucas Lima, Franz Anthony of Studio 252mya for several illustrations throughout this episode. You can find more of their work here:

    Produced in collaboration with PBS Digital Studios:

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  • Runtime : 10:28
  • dinosaurs dinos paleo paleontology scishow eons pbs pbs digital studios hank green john green complexly fossils natural history triploblastic diploblastic burgess hemoglobin hemocyanin hemerythrin blood circulatory systems evolution burgess shale cambrian Marrella bilateral symmetry globin heme globin fold purple red green white blue


  • takitaki rumbah
    takitaki rumbah   1 days ago

    Then how can there be no life on other planets when some kind of fish that lived 600m years ago developed blood from copper

  • Glob Animations
    Glob Animations   3 days ago

    Pbs Eons:living things have bloodMe: DO PLANTS HAVE BLOOD

  • mem Sisters
    mem Sisters   6 days ago

    Need to know connection between hemoglobin, and cytochromes, myoglobins, ISC iron sulpher cluster in mitochondri

  • Donny Sandley
    Donny Sandley   1 weeks ago

    I just saw a girl cooking a horseshoe crab and I'll tell you they don't look anything like I thought they would on the inside 😳

  • BookUnbinder
    BookUnbinder   1 weeks ago

    Snails evolving hemocyanin like that queen on Drag Race who doesn't know how to sew, meanwhile octopodes are LIVING.

  • Topten Dawg
    Topten Dawg   2 weeks ago

    Omgosh like what is these guys life like.Guys: ok finished report of newly discovered species...nothing new apparently... next!

  • A. N.
    A. N.   2 weeks ago

    Biliverdin sounds sick as h*ck.

  • hagala
    hagala   2 weeks ago

    no what gives blood the read colour is communism

  • Robert Eischen
    Robert Eischen   2 weeks ago

    I learned word hemoglobin is pretty fun to say. I'm not too bright though. 😅

  • HonorisCreed
    HonorisCreed   2 weeks ago

    Thank you for teaching me that I have a slight fear of blood.

  • first last
    first last   3 weeks ago

    But arthropods don't have a circulatory system I thought? That's why insects can't grow too thick because they need to get oxygen from opening in their exoskeleton which can't penetrate very deep, I thought?

  • Corleone
    Corleone   3 weeks ago

    I didn't expect a cuckold to be commentating for PBS

  • M P
    M P   3 weeks ago

    We were squids, THEN we were kids.

  • Gustavo Pomar
    Gustavo Pomar   3 weeks ago

    After the second or third "improvement" (mutation), who might've been the lucky ones that survived and were even able to reproduce!!! One really needs lots, I mean loooooots of faith to believe this.

  • _R.N.04_ Bluefaceb
    _R.N.04_ Bluefaceb   3 weeks ago

    Anyone else smart that watches videos at 2x speed and still understands them, you can get thru so many videos

  • jacob reww
    jacob reww   3 weeks ago

    How can you dislike everything?! XD

  • I Scream for Ice Ring

    5:44 LOL!!! Did you know shells of living snails carbon date to 100,000 years old?

  • Helljumper
    Helljumper   3 weeks ago

    Can a human lose their consciousness?

  • Zane Finlay
    Zane Finlay   3 weeks ago

    Evolution of sap and other mechisms that plants/trees/fungi use

  • Gender Woman
    Gender Woman   3 weeks ago

    What's the difference between a tapeworm and a human embryo?Tapeworm has other kind of blood than his host...

  • Gender Woman
    Gender Woman   3 weeks ago

    There's an iron.So that's why fresh blood smells like warm metal...

  • Gender Woman
    Gender Woman   3 weeks ago

    4:23-What's that colorful painting? Is it Picasso's?-It's blood.

  • JustSay That
    JustSay That   4 weeks ago

    A Mosquito that was hacking internet just found this video!

  • magnum opus
    magnum opus   1 months ago

    Looks likes Piccolo's blood has hemerythrin who knew 😀

  • Nime Ano
    Nime Ano   1 months ago

    This is what youtube shall be use for 👍🏿

  • bulruq
    bulruq   1 months ago

    Here's an idea worthy of investigation: Does carbon monoxide poison these different types of blood equally or are some more resistant to its' toxic effects?

  • K Sage
    K Sage   1 months ago

    I love this channel so much!