How Blood Evolved (Many Times)

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  • Опубліковано 16 тра 2024
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    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: 252mya.com/
    Produced for PBS Digital Studios.
    Super special thanks to the following Patreon patrons for helping make Eons possible:
    Katie Fichtner, Anthony Callaghan, Renzo Caimi Ordenes, John Vanek, Neil H. Gray, Marilyn Wolmart, Esmeralda Rupp-Spangle, Gregory Donovan, Ehit Dinesh Agarwal, الخليفي سلطان , Gabriel Cortez, Marcus Lejon, Robert Arévalo, Robert Hill, Kelby Reid, Todd Dittman, Betsy Radley, PS, Colin Sylvester, Philip Slingerland, Jose Garcia, Eric Vonk, Tony Wamsley, Henrik Peteri, Jonathan Wright, Jon Monteiro, James Bording, Brad Nicholls, Miles Chaston, Michael McClellan, Jeff Graham, Maria Humphrey, Nathan Paskett, Connor Jensen, Daisuke Goto, Hubert Rady, Yuntao Zhou, Gregory Kintz, Tyson Cleary, Chandler Bass, Maly Lor, Joao Ascensao, Tsee Lee, Sarah Fritts, Ruben Winter, Ron Harvey Jr, Jacob Gerke, Alex Yan
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    References:
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    www.mdpi.com/2308-3425/2/1/2/pdf
  • Наука та технологія

КОМЕНТАРІ • 3 тис.

  • @eons
    @eons  3 роки тому +465

    Our friends over at Bizarre Beasts made a spectacular video about the clear blood of the crocodile icefish. It also happens to be hosted by a familiar face...ua-cam.com/video/DtufV5JZLW4/v-deo.html

    • @kanyenorth5711
      @kanyenorth5711 3 роки тому +4

      6 hours ago wow

    • @fzirybells
      @fzirybells 3 роки тому

      woah

    • @bonbin6053
      @bonbin6053 3 роки тому

      Yes

    • @davidt8087
      @davidt8087 3 роки тому +2

      I hated evolution, kept denying it. Watched this channel and then started to think its true. Then you get to the point right here whwre they say "we know it happened but there's no evidence, oh and somehow of course the first organism somehow "evolved" and survived it's initial selection and both genders somehow found each other, or one organism somehow could produce. Even worse go back all the way to the first organism. It comes alive. Then dies. Because it didn't reproduce and because it didn't have the genetic code to reproduce, it couldn't have survived and it died.

    • @dorongrossman-naples9207
      @dorongrossman-naples9207 3 роки тому +12

      @@davidt8087 The first organisms didn't have genders. They were single-celled and probably reproduced by fission (splitting into multiple parts), like bacteria do today.

  • @Twatical
    @Twatical 5 років тому +7262

    You've done nothing but inform the mosquito army of our greatest secret.

  • @15SecNut
    @15SecNut 5 років тому +8193

    How the hell did butterflies evolve to melt themselves and reform into a completely different shape?

    • @reeba4824
      @reeba4824 5 років тому +1580

      Ppl find it normal but seriously, that is such a mind blowing change! Lol it always amazed me

    • @royjonesrampage6684
      @royjonesrampage6684 5 років тому +172

      pretty sure there was a video about it first find the correct term for it via google then put that term n youtube

    • @15SecNut
      @15SecNut 5 років тому +1292

      @Agent J Maybe I just want Eons' presentation and commentary on the subject because they're entertaining? But I wouldn't expect someone with a rick and morty profile pic to realize watching disjunct youtube videos doesn't count as education.

    • @naturalLin
      @naturalLin 5 років тому +57

      This is a good question.

    • @Dragrath1
      @Dragrath1 5 років тому +431

      Metamorphosis is a trait found in a far wider array of insects than just butterflies! Beetles, wasps flies, lepidoptera(moths but note that butterflies are actually a diurnally specialized lineage of moths) From what I have read they really didn't appear on the scene until after the Great dying opened up the opportunity to diversify. I really wonder what they were like before diversifying? The older orders of insects all have incomplete-metamorphosis with both nymphs and adult forms (examples being Dragonflies, Antlions, True Bugs such as Aphids Roaches/Mantids(including Termites) etc. which is more like shedding a different skin)

  • @Gay_Priest
    @Gay_Priest 4 роки тому +2103

    Family: blood is thicker than water
    Me: *angry ice fish noises*

    • @THSmjsmith
      @THSmjsmith 4 роки тому +5

      Silver theDragon that doesn’t even make sense why does this have 140 likes

    • @Gay_Priest
      @Gay_Priest 4 роки тому +12

      THS_mjsmith YT 9:00

    • @kevintan5497
      @kevintan5497 4 роки тому +31

      technically speaking ice is less dense than liquid water

    • @halomaster213
      @halomaster213 4 роки тому +3

      Silver theDragon it still doesn’t make any sense. You’re not supposed to make the sound the fish is supposed to.

    • @Gay_Priest
      @Gay_Priest 4 роки тому +26

      Halomaster 213 yes. Ice fish noises, and it’s angry

  • @johncnorris
    @johncnorris 4 роки тому +762

    Dracula: I want to drink your iron based protein structures with hemogloben designed to transport oxygen.
    Scientist: Yeah, okay.

    • @jollyjokress3852
      @jollyjokress3852 3 роки тому +14

      HAHA.

    • @cxffaye
      @cxffaye 3 роки тому +5

      LOL 😂

    • @neolexiousneolexian6079
      @neolexiousneolexian6079 3 роки тому +36

      Haha, I swapped it out with cyanoglobin, PRANKED!!!
      (Also sheesh I feel woozy, my body's not meant to run off this copper stuff- *thud.)*

    • @rainbowruler6453
      @rainbowruler6453 2 роки тому

      WHY

    • @EmpressLizard81
      @EmpressLizard81 Рік тому +1

      Which is why Lestat surviving on alligator swamp blood would be a completely absurd proposition. (Assuming, you know, vampires existed.)

  • @iNuuutz
    @iNuuutz 5 років тому +3810

    PBS Eons: *releases video about blood*
    Mosquitoes: *Heavy breathing*

    • @ImTheBatchMan
      @ImTheBatchMan 5 років тому +152

      @@LapisOverlord
      Mosquitoes: *Heavy oxygen absorption through skin*

    • @demetraeconomou6096
      @demetraeconomou6096 5 років тому +18

      @@ImTheBatchMan you two made the joke 10x better

    • @wesleymcspadden5437
      @wesleymcspadden5437 5 років тому +1

      @@LapisOverlord it still is a joke tho it doesn't have to be logical

    • @AwesomeYena
      @AwesomeYena 5 років тому +7

      *Mosquitoes swarm around my tablet* HEY!! SHOO!

    • @thecursed01
      @thecursed01 5 років тому

      vampires

  • @JoaoPedro-qp9cw
    @JoaoPedro-qp9cw 5 років тому +2763

    That guy asking for the blood video since forever must be very happy

    • @abyssstrider2547
      @abyssstrider2547 5 років тому +81

      Everyone did ask, after all so many people were curious about it.
      Im sure you were, as well

    • @maan7715
      @maan7715 5 років тому +69

      I was thinking the same
      "oh my god, that guy must be so happy now, after all this time we got the blood video!" XD

    • @monsoon_magic2874
      @monsoon_magic2874 5 років тому +31

      Extend a thanks to that guy as well.

    • @super00su
      @super00su 5 років тому +7

      @@TheGroovyWalrus ua-cam.com/video/UcwfEMdV-aM/v-deo.html

    • @Dragrath1
      @Dragrath1 5 років тому +24

      I honestly didn't know how they would really be able to cover it but they pulled it off despite the limited evidence in the fossil record

  • @JonathanRootD
    @JonathanRootD 4 роки тому +1578

    What blows my mind is that for around 90% of Earth's existence we only had simple life. Larger complex life didn't arise until much more recently.

    • @DanielDavies347
      @DanielDavies347 4 роки тому +103

      Jonathan Root i would argue larger more complex life is yet to come

    • @wrathayush
      @wrathayush 4 роки тому +38

      @@DanielDavies347 exponential growth

    • @wrathayush
      @wrathayush 4 роки тому

      Maybe

    • @rontayan
      @rontayan 4 роки тому +70

      Wait until we get nanotechnology and cybernetics online. Things are really going to get complicated.

    • @louistournas120
      @louistournas120 4 роки тому +14

      +Jonathan Root:
      Simpler lifeforms have more potential to change than complex systems. By simple, I mean unicellular life forms.

  • @theshermanator5156
    @theshermanator5156 4 роки тому +618

    “They all have bilateral symmetry”
    Flatfish: “Am I a joke to you?”

    • @meghanachauhan9380
      @meghanachauhan9380 4 роки тому +29

      NO YOU ARE FOOD TO ME

    • @MichielGlas
      @MichielGlas 4 роки тому +49

      Correct me if I am wrong, but don't they start out vertical and over time flatten out? www.nationalgeographic.com/news/2016/08/flatfish-animals-science-colors-flounders/ Check out this article that mentions that.

    • @DarkMoonDroid
      @DarkMoonDroid 4 роки тому

      IKR?

    • @spindash64
      @spindash64 4 роки тому +62

      They aren’t mirror images, but that’s not the point: they have a clear front and back, and a clear top and bottom. Bilateral symmetry is oddly not about where things are the same, but about how many directions are unique. A sponge is a rather formless blob that can make do with almost any shape. A Jellyfish has more order to it, but still is more or less just a ring. A Flatfish, on the other hand, has distinct parts that aren’t just “bumps”: it has a head where the eyes, brain, and mouth are located. It has a tail/aft section. It has a spine running along its body, from the head to the tail, also giving a direction.

    • @HappyBeezerStudios
      @HappyBeezerStudios 4 роки тому +12

      The flatfish basically lays on it's side and decided that not looking at the ground all the time was a good idea.

  • @NaturesTemper
    @NaturesTemper 5 років тому +3701

    I'd love to see how hair evolved. And the difference between mammal and arthropod hair.

    • @Leto85
      @Leto85 3 роки тому +116

      That would be interesting. I thought it was made of the same material as nails, claws, and I thought scales as well. It's probably evolved from that.

    • @justherald1117
      @justherald1117 3 роки тому +90

      @@Leto85 keratin, I believe

    • @KlavierMenn
      @KlavierMenn 3 роки тому +50

      @@Leto85 If I am not mistaken, hair appeared on the late Carboniferous/early Permian

    • @Changitojuanito
      @Changitojuanito 3 роки тому +21

      I second this request 🧐

    • @BierBart12
      @BierBart12 3 роки тому +66

      I read about arthropod hair before, and the way it evolved was REALLY weird.
      I think they started out as legs, with each species evolving them to a very specific purpose like feelers, hair or MORE LEGS
      Correct me if I'm wrong.

  • @Roxanewolfie
    @Roxanewolfie 5 років тому +4392

    i see lots of people saying 'finally' but not enough saying 'thank you', so... thank you for making the video so many of us asked for!!

    • @fransoto8343
      @fransoto8343 5 років тому +44

      *insert THANK YOU gif*

    • @fransoto8343
      @fransoto8343 5 років тому +30

      @@pullupullupullup4687 well...
      I don't know... Maybe you could go and search it on Wikipedia or somewhere more reliable than a simple UA-cam video.

    • @zddxddyddw
      @zddxddyddw 5 років тому +59

      @@pullupullupullup4687 You're wrong. Blood is a tissue composed mainly by plasma, red and white blood cells, platelets and dissolved gases, nutrients and enzimes. There are no microorganisms. Cells have organelles, not "organs", and of those, the only one with a symbiotic origin is the mitochondria, the other organelles are just, generally speaking, internal extensions of the cell membrane or protein-based structures (like microtubules). Blood cells work pretty much like any other cell in your body (of course, with specializations for the roles they fulfill). There are no microorganisms interacting in your blood (unless you have an infection of some kind).

    • @zddxddyddw
      @zddxddyddw 5 років тому +49

      @@pullupullupullup4687 Also, they said all that they could about the evolution of blood. Like Hank said in the video, less complex animals just move gasses, nutrients and metabolic waste by diffusion through their body walls and internal fluids. All we can say without a doubt about the evolution of blood is that, at some point, animals developed proteins in ther internal fluids that allowed them to transport gases and nutrients more effectively, and thus they could get more and more complex. Not much more than that. You have to undestand that studying the evolution of soft tissues is already hard enough in the fossil record, studying a liquid tissue is even harder, even with tools such as the molecular clock. They even showed in the video when the different blood proteins probably appeared.

    • @AnalyticalReckoner
      @AnalyticalReckoner 5 років тому +2

      How many is enough?

  • @mooxim
    @mooxim 3 роки тому +410

    As a dungeon master for d&d, I need to make a solid mental note about this. Lizards and lizardfolk can have green blood, arthropods can have blue blood, worms can have purple blood (awesome) and arctic beasts can bleed a clearish, white blood.
    I might stick with describing arctic beasts having red blood because I'd like to avoid unnecessary semen jokes and the mental image of red blood on white snow is always very evocative.

    • @akulsinator7680
      @akulsinator7680 2 роки тому +35

      You can make it yellow or maybe orange like fire a contrast to their environments

    • @TheAnimewolfchick
      @TheAnimewolfchick Рік тому +14

      @@akulsinator7680 yeah but that makes me think of injured/dead bugs

    • @stoneraptor6219
      @stoneraptor6219 Рік тому +8

      Could be a large difference in shade or saturation if you wanted to use blue blood again for the arctic creatures that don’t fall under other category

  • @ferna2294
    @ferna2294 5 років тому +629

    Amazing. First time I hear about copper being used instead of iron.
    Great job, perfectly explained.

    • @txikitule
      @txikitule 5 років тому +14

      What about Vulcan like Dr Spock?

    • @scottc346
      @scottc346 4 роки тому +14

      @@txikitule Dr. Spock was human....MR. Spock was Vulcan.

    • @newname3718
      @newname3718 4 роки тому +12

      I have always called this system Blue = copper core, red = iron core.

    • @glenhill9884
      @glenhill9884 Рік тому +2

      @@scottc346 Mr. Spock was half human, half Vulcan.

    • @grell5108
      @grell5108 Рік тому +2

      All the Trekkies: _really?_
      Huh, what a surprise :D

  • @vinicius2uiciniv
    @vinicius2uiciniv 5 років тому +1594

    *The BLOOD video, YESSSSSSSS!*

    • @iancarreras9893
      @iancarreras9893 5 років тому +55

      what are you a vampire

    • @violentbenevolence
      @violentbenevolence 5 років тому +44

      it was a bloody good idea for them to post it

    • @aamirrazak3467
      @aamirrazak3467 5 років тому

      Are you related to Vinicius jr the soccer player

    • @vinicius2uiciniv
      @vinicius2uiciniv 5 років тому +3

      @@aamirrazak3467 Not at all, 'Vinícius' is just a common Portuguese/Brazilian name, not a surname

    • @cadenrolland5250
      @cadenrolland5250 5 років тому +2

      They were working on it, planning, researching, editing, recording, and today UPLOADING!

  • @ericman5455
    @ericman5455 5 років тому +1379

    You could say thats a bloody good subject

  • @samuelbarrow5502
    @samuelbarrow5502 4 роки тому +199

    Gives a whole new meaning to “we all bleed red”

  • @CargodHera
    @CargodHera 3 роки тому +118

    Thank you, Hank Green for explaining even the most complex subjects in an entertaining and engaging way.

    • @CargodHera
      @CargodHera 11 місяців тому

      @✪Hidden I know, poor baby. I love him and his brother so much!

  • @deancyrus1
    @deancyrus1 5 років тому +2523

    I understood about 5% of that. That's 5% more than i knew before. Really interesting stuff thanks.

    • @EGarrett01
      @EGarrett01 4 роки тому +18

      These PBS channels, for one reason or another, seem to deliberately obfuscate the topics, focusing on jargon terms instead of what they actually represent.

    • @souleevands5964
      @souleevands5964 4 роки тому +119

      @Everett01 It’s a science channel, they’re meant to communicate to other scientists who find the information useful, so it really should not be something to criticize for.

    • @EGarrett01
      @EGarrett01 4 роки тому +64

      No, scientists communicate with other scientists through academic journals.

    • @martinalberter6369
      @martinalberter6369 4 роки тому +135

      This is a wonderful level of explanation for late high school and early BSc level EEE biology

    • @souleevands5964
      @souleevands5964 4 роки тому +44

      Everett01 oh I’m sorry that the desk is considered a table
      Just stay off the platform if you think the vocabulary is too complicated for you

  • @enderflashria3597
    @enderflashria3597 5 років тому +426

    *the question I've seen in the comments of every single video and its finally here*

    • @Flarezap
      @Flarezap 5 років тому +4

      Still waiting for the grass video though

  • @Manoto17
    @Manoto17 5 років тому +103

    I’m glad there’s channels like these or else I’d be watching meme compilations and meme review all day.

  • @itzakhywell7668
    @itzakhywell7668 5 років тому +528

    Excellent video, but you omitted the fact that orcs have black blood...

    • @fabkingpuma554
      @fabkingpuma554 4 роки тому +23

      Orc joined the chat

    • @drizzmatec
      @drizzmatec 4 роки тому +18

      Dis hears an Orky thread now boyz!!! WAAAAAAAGH!!!!

    • @lukelim5094
      @lukelim5094 4 роки тому +7

      @@drizzmatec them blood Boyz need some waghh

    • @matthewvanburen6415
      @matthewvanburen6415 4 роки тому +6

      Or Vulcans having green blood.

    • @celinak5062
      @celinak5062 4 роки тому +10

      @@matthewvanburen6415 so they're lizards 8:45

  • @Shaden0040
    @Shaden0040 5 років тому +587

    If life had to adapt to a snowball Earth at least twice, that would explain why copper was adopted early on to fix oxygen in their blood. As copper works better in cold temperatures. So it makes sense that life coming out of this snowball Earth used copper as they diversified into the Ediacaran period life forms.

    • @MasterJedi86
      @MasterJedi86 5 років тому +41

      I never thought of it that way.

    • @aniekanumoren6088
      @aniekanumoren6088 5 років тому +131

      Cool hypothesis

    • @kotanightshade8989
      @kotanightshade8989 5 років тому +94

      Also copper being a softer metal than iron may have eroded from the land into the oceans faster when complex life was evolving

    • @bryal7811
      @bryal7811 5 років тому +59

      @@aniekanumoren6088 oof, that pun is so far under the radar it's sub-zero

    • @dandanthedandan7558
      @dandanthedandan7558 5 років тому +41

      @@bryal7811 Yo, no need to call em out on that. Why don't we just _chill_ for a moment?

  • @nolanwestrich2602
    @nolanwestrich2602 5 років тому +344

    I've seen at least 3 comments asking for this episode, and I thought the idea was too. Thanks for the video!

    • @gibranhenriquedesouza2843
      @gibranhenriquedesouza2843 5 років тому +2

      I hope one day I will see a completo video about fossilization process.

    • @botas5254
      @botas5254 5 років тому +2

      The idea was too what? I don't understand

    • @nolanwestrich2602
      @nolanwestrich2602 5 років тому +9

      @@djimma5080 I meant to say "I thought the idea was _cool,_ too." I don't know how I missed adding the word "cool". Maybe I should my comment before I hit Ctrl-Enter.

    • @kamoroso94
      @kamoroso94 5 років тому

      @@nolanwestrich2602 you can still edit it.

    • @ImmiGaru96MuraSaki
      @ImmiGaru96MuraSaki 5 років тому +3

      @@nolanwestrich2602 Should what?

  • @commanderrockwell1123
    @commanderrockwell1123 4 роки тому +41

    Hank Green shows up at PBS, too?! He’s everywhere!

  • @JennieWrenStar
    @JennieWrenStar 5 років тому +57

    I’m home now and going through my emails. It’s so weird for me, this video was being shown, whilst I was in the process of having a full blood transfusion to save my life, then I needed another few units a month later. Three months in hospital was long enough. When I was younger I used to give blood until my body became too medicated.
    To all the people that donated the blood that saved my life, Thank You. If you are young and healthy enough to donate please do so.

  • @xxxsimedxxx
    @xxxsimedxxx 5 років тому +270

    You made a little mistake.
    seastars belongs like all members of the Echinodermata to the group Bilateria. It's may misleading that adult seastars don't show a bilaterally symmetrical body but the embryos of Echinodermata are bilaterally symmetrical at the beginning.
    Anyway
    Thank you guys for this amazing video. Eons is one of the best UA-cam channels ever! PLEASE DON'T STOP

    • @creppruby
      @creppruby 2 роки тому +1

      well i think if you divide a seas star in half through the top leg then it’s bilaterally symmetrical

    • @xxxsimedxxx
      @xxxsimedxxx 2 роки тому +2

      @@creppruby key point of bilateral symmetry is that you only have one axis that divides the animal im two symmetrical parts. Since you could use every leg of a seastar as a beginning point the adult seastar is radial symmetric.

  • @jj-qr4ro
    @jj-qr4ro 5 років тому +420

    I gasped out loud multiple times when watching this! Science is so interesting thank you for providing another platform to make science more accessible

    • @Proftheskidkid
      @Proftheskidkid 5 років тому +11

      @J Austin Science is the gathering of knowledge. He wasn't wrong in calling it science. The study of history is a science.

    • @TheGuruNetOn
      @TheGuruNetOn 4 роки тому +1

      @J Austin Actually it's the science of evolution of the circulatory system.

    • @evilpimp2475
      @evilpimp2475 4 роки тому +2

      You didn't really gasp out loud at a video...

    • @pickledpeckers7789
      @pickledpeckers7789 4 роки тому +2

      Nerd

    • @Paxton550730
      @Paxton550730 3 роки тому +1

      Get naenaed on dork

  • @thilanbalasuriya6188
    @thilanbalasuriya6188 11 місяців тому +6

    Wonders of evolution is much more mind blowing than any methodology or religion ...

    • @Kitty-xi1sb
      @Kitty-xi1sb 11 місяців тому +5

      "This is too complex, so God"

  • @betobermudez4075
    @betobermudez4075 5 років тому +19

    The people demanded blood, and blood they got. Thank you PBS Eons!

  • @lefleurdulmal
    @lefleurdulmal 5 років тому +62

    They've gone and bloody done it

    • @boy123838
      @boy123838 5 років тому +1

      Hahaahahhahahahhahahhaha
      No.

  • @shrimpbisque
    @shrimpbisque 5 років тому +129

    YES! I was one of the ones who commented asking for this video, and specifically the differences between the different blood proteins! I'm trying to write an advanced alien race with blue or green blood, and I wanted to know how to make it scientifically viable. Since hemocyanin is better in lower temperatures, I may have to scooch their planet back a smidge.

    • @robinbowman1926
      @robinbowman1926 5 років тому +27

      You could also still use hemoglobin, but say that other proteins, compounds and/or minerals in the blood contribute to a different colour.
      In addition, arthropods here on Earth, have hemolymph and don't distinguish between a circulatory system and a lymphatic system.
      You could also say that these aliens use a completely different metabolic system which doesn't use oxygen, in that case the transport proteins for gas exchange could be wildly different.
      Just some things to think about, if you didn't already. Good luck on the world building.

    • @marcogarcia7944
      @marcogarcia7944 5 років тому

      Shrimp Bisque same here wanted to make aliens but there was one detail not right and that was how they transported nutrients and oxygen and how that evolved yet this video helped a lot on that

    • @garyreed2206
      @garyreed2206 5 років тому

      Have you read the "Giants" Trilogy by James Hogan. The aliens in this series had an interesting blood physiology. I won't give any other spoilers, in case you want to discover these stories for yourself.

    • @limiv5272
      @limiv5272 5 років тому +5

      There's no reason why an alien species would have a protein in their cells, which utilize the same 20 amino acids as us, and that has the same fold and general structure of hemocyanin. You should probably just make up an entirely different sort of molecule, but have it use the same principles, like having a copper atom that does the actual binding to oxygen, because the basic rules of chemistry should still apply

    • @jj-qr4ro
      @jj-qr4ro 5 років тому

      Oooh where are you writing it? I’d love to give it a read

  • @bast713
    @bast713 Рік тому +11

    I see science I click. I hear Hank's voice and I immediately smile because I know it's going to be well explained.

  • @thunderflare59
    @thunderflare59 4 роки тому +34

    "Blood can be green..."
    *Spock wants to know your location*

    • @costrio
      @costrio 3 роки тому

      He is green (blooded) with envy?

  • @RickySTT
    @RickySTT 5 років тому +161

    2:54 Despite their adult appearance, sea stars are phylogenetically bilateral animals (Eumetazoa, Bilateria, Nephrozoa (≈Coelomata), Deuterstoma, Echinodermata, Asterozoa, Asteroidea). Their blood is degenerate compared to other bilaterians, but they do indeed have an internal body cavity and an active circulatory system, unlike sponges, jellies, and ctenophores.

    • @thismianeptunis
      @thismianeptunis 5 років тому +29

      I'm glad somebody mentioned this! People deserve to know about the glorious weirdness of starfish - starting out as bilaterally-symmetric larvae and then flopping on their sides as adults to completely restructure their bodily symmetry

    • @levihuttner3260
      @levihuttner3260 5 років тому +6

      thank you! I was confused when he said all the descendants of that hypothetical bloody common ancestor have bilateral symmetry, and then pointed to sea stars as an example of non-bilateral symmetry :P. They should really have made this more clear in the video.

    • @TheRedKnight101
      @TheRedKnight101 5 років тому +8

      Especially seeing as Starfish are some of our closest invertebrate relatives

    • @Chris_da_fro
      @Chris_da_fro 5 років тому +2

      Glad I came to read the comments

    • @bensutcliffe1975
      @bensutcliffe1975 5 років тому +1

      Imagine if they lived on land

  • @themonsterbaby
    @themonsterbaby 5 років тому +426

    The evolution of venom and poison....

    • @martinalberter6369
      @martinalberter6369 4 роки тому +26

      That is very unique, as most examples evolved it individually and convergently. Almost always from some other protein they used or excreted, or sometimes sequestered from their food, and each example has a unique pathway.

    • @GenderWoman666
      @GenderWoman666 4 роки тому +2

      It should be: The evolution of Venom...

    • @_Muzolf
      @_Muzolf 4 роки тому +6

      Many kinds of venoms double as digestive fluids, so most probably evolved from that. Poison is even easier, some species or populations being less edible to predators is already an advantage without it being outright poison, with your predators providing an evolutionary pressure, your evolution is driven in a direction where the bodies of each generation are more and more toxic, to the point where it is not just a happy coincidence that your body fluids are poisonous to someone else, you outright produce poison that no longer has any other function.

    • @spindash64
      @spindash64 4 роки тому +4

      Z Zs
      Really, deliciousness is just a bizarre inversion that happens when someone thinks your species is SO delicious that they want to make sure there will always be enough of you around that they have something delicious.
      Actually, Livestock, from their perspective, accidentally pulled off a weirdly successful sacrificial lamb gambit: a lot get eaten, but those that breed have extremely high odds of getting their lineage to continue

    • @Sara3346
      @Sara3346 4 роки тому

      @@spindash64 To be fair what with milk goats, dairy cows and Egg producing chickens are a thing too. Aphid Husbandry in ants might also be worth noting.

  • @yoyo8077
    @yoyo8077 3 роки тому +3

    This is officially my favourite UA-cam channel

  • @misstruly5482
    @misstruly5482 3 роки тому +73

    I LOVE THIS SHOW-- brings me a great sense of peace, actually... getting some perspective on the relative novelty of the human species, and seeing that life itself has persisted in all imaginable climes and crises, against the odds. Even pandemics and the collapse of civilizations got nothing on the violent end to the Mesozoic era. Thank you for enriching us and comforting us with knowledge. The pursuit of knowledge, the hunger for wisdom, and the light of Truth can save us all. Stay strong

    • @GgTTV828
      @GgTTV828 Рік тому +1

      I love this comment!

  • @Xagzan
    @Xagzan 5 років тому +151

    "Deliciously."
    - Dracula probably

    • @vinny9868
      @vinny9868 5 років тому +2

      Blood of different colors and flavors.

    • @qetyghg9448
      @qetyghg9448 4 роки тому

      Mosticquo

  • @evaristegalois6282
    @evaristegalois6282 5 років тому +338

    Favorite color: *the blood of my enemies*

    • @rock3tcatU233
      @rock3tcatU233 5 років тому +19

      Noob, real men enslave their enemies.

    • @BigBoss-sm9xj
      @BigBoss-sm9xj 5 років тому +20

      Real men eat their enemies!

    • @eruyommo
      @eruyommo 5 років тому

      Evariste Galois. You're starting to become the new Justin. I.e.: you're everywhere.

    • @ShapeDoppelganger
      @ShapeDoppelganger 5 років тому +4

      Then, much to your dismay, you realize that the blood of thy enemies and thy family are tinted just the same, and with the same rusty stink.

    • @bangbangliu2146
      @bangbangliu2146 5 років тому +3

      @@rock3tcatU233 Noob, real men get offended because yOU USed "mEn" aNd thAT iS sEXIst

  • @LEDewey_MD
    @LEDewey_MD 4 роки тому +27

    Having only recently stumbled onto PBSeons, now I'm perusing previous episodes. This episode is very well done, especially considering the complexity of the subject. Lots of biochemistry to consider - and the remarkable feat of elucidating it!

  • @lardyify
    @lardyify 4 роки тому +77

    Some geese use a different blood protein altogether: hemoaurelium, using gold as the metallic pigment.

    • @preacherjohn
      @preacherjohn 4 роки тому +13

      Haha! XD en.wikipedia.org/wiki/The_Goose_That_Laid_the_Golden_Eggs

    • @ACBmonkey
      @ACBmonkey 2 роки тому

      I can't find any info on this would you happen to have a link you could share?

    • @genghiskhan6809
      @genghiskhan6809 2 роки тому

      Wat!!!

    • @rainsy8567
      @rainsy8567 3 місяці тому

      Golden goose egg :3

  • @shadowmax889
    @shadowmax889 5 років тому +323

    Evolution of plants would be nice

    • @ganaraminukshuk0
      @ganaraminukshuk0 5 років тому +12

      There's more than one chemical you can use to photosynthesise; in other words, like hemoglobin, there are compounds that work like chlorophyll. (I forgot the name of it but it's purple/violet; that's all I know.)

    • @nab.7250
      @nab.7250 5 років тому +3

      Evolution is not real

    • @jcskehan
      @jcskehan 5 років тому +2

      Too broad of a topic I think...
      They already covered tress in the carboniferous video.
      A quick one on flowering plants would be cool, but it's kind of a basic subject.
      Maybe they could focus instead on under-water plants in particular? Or maybe algae in its many forms?

    • @adlsfreund
      @adlsfreund 5 років тому +8

      @@nab.7250 the internet is not real. you're a figment of my imagination.

    • @Dragrath1
      @Dragrath1 5 років тому +2

      @@ganaraminukshuk0 Yes there are quite a few different methods of photosynthesis. Chlorophyll is unique in that it is aerobic uses oxygen or more specifically breaks down water and CO2 releasing oxygen as a byproduct which has a higher chemical potential than other molecules do allowing more energy per molecule but other forms of photosynthesis evolved billions of years earlier.
      The most familiar of these is the purple microbes that utilize sulfur instead H2S-> SO4 etc. (though there are different types) but who knows how many types of photosynthesis occurred before the atmosphere was oxygenated effectively killing off most microbes....
      I remember reading a paper about some type of Iron based photosynthesis which is quite different in that its basically impossible on modern Earth unless you have an extremely anaerobic environment....

  • @RideWitMe1
    @RideWitMe1 5 років тому +176

    Do the evolution of egg laying mammals next.

    • @last9up
      @last9up 5 років тому +5

      Ooh this one sounds really interesting.

    • @craigme2583
      @craigme2583 5 років тому +7

      Answer one of lifes greatest questions...what came first...the chicken or the egg...

    • @synonymous1079
      @synonymous1079 5 років тому +11

      @@craigme2583 the chegg.

    • @doomsdoor
      @doomsdoor 5 років тому +6

      @Davvy Jannes well you could say that each generation of chicken is different from the last so that the egg does come before the chicken, also that chickens evolved from animals that laid eggs. Just a bad question

    • @jayasuryangoral-maanyan3901
      @jayasuryangoral-maanyan3901 5 років тому +13

      Its a bit like placental mammals but they didn't get to the placenta part.
      Not to say it's not interesting but you made it sound like they may have gone from placental to egg-laying. Which is a no from my knowledge

  • @Zoe_EK
    @Zoe_EK 5 років тому +70

    Me as a biochemistry student getting really excited about all the PyMol protein structures... Just beautiful😭💕🎉

    • @Fluor488
      @Fluor488 5 років тому +14

      This may be late but I want to major in biochem, any tips or suggestions that would help me better figure out what the biochem major is like?

    • @namitaseshadri2638
      @namitaseshadri2638 3 роки тому +1

      @@Fluor488 hey, sorry this reply is also very late! i’m a biomedical science major (not biochem) but i seriously considered majoring in biochem. basically you take a LOT of chemistry classes from biochem and orgo to analytical chemistry and stuff so definitely don’t go into it if you don’t love chemistry. my university also offers lots of interesting molecular bio courses about the immune system and stuff as a part of the biochem degree. you’ll also need to get a decent foundation in physics and calculus.

    • @AmanExplorerBoy
      @AmanExplorerBoy 3 роки тому

      @@namitaseshadri2638 you are from India? If so then carrying your studies/work here or abroad?

    • @namitaseshadri2638
      @namitaseshadri2638 3 роки тому +1

      @@AmanExplorerBoy i’m of indian descent but i’m born and raised in Canada and i go to uni in canada:)

  • @coineineagh
    @coineineagh 4 роки тому +14

    As a biology student and shell collector, I'd love to see a summary of mollusks' evolutionary history. They're quite beautiful, and their adaptations to live on land and the extreme deep sea are fascinating.

  • @matthewstewart5566
    @matthewstewart5566 5 років тому +70

    "We are born of the blood, made men by the blood, undone by the blood."

  • @carterkc6429
    @carterkc6429 5 років тому +65

    Hank Green. Works on PBS Eons, The Sci Show, and also the founder of Vidcon.

    • @AlteryxGaming
      @AlteryxGaming 5 років тому +19

      Don't forget he helped found Crash Course along with his brother, John Green.

    • @carterkc6429
      @carterkc6429 5 років тому +3

      @@AlteryxGaming Lol I only knew about those three things XD

    • @imortalones
      @imortalones 5 років тому +3

      i've spent months of my life following these guys no joke and no regret. They are probably getting super rich. Also love those old Green blood zombie etc videogames from back in the day.

    • @viniciusgheolan
      @viniciusgheolan 5 років тому +5

      also bestselling author with "An Absolutely Remarkable Thing"

    • @alir8391
      @alir8391 4 роки тому +1

      @@viniciusgheolanOn the New York times bestsellerist and In stores now in paperback 😉. And obviously co-founder of vlogbrothers, Journey into the microcosm, DFTBA Records and Nerdfighteria

  • @tislex
    @tislex Рік тому +5

    Incredibly ironic that youtube recommended this to me after the news about Hank. Get well soon!

  • @thunder_2124
    @thunder_2124 5 років тому +94

    I've been waiting for this for so long.

  • @soerry2
    @soerry2 5 років тому +133

    We are born of the blood,
    made men by the blood,
    undone by the blood.
    Fear the old blood!

    • @BigBoss-sm9xj
      @BigBoss-sm9xj 5 років тому +1

      Cool!

    • @edwartexe
      @edwartexe 5 років тому +5

      Fear the purple blood then?

    • @jeremybyington
      @jeremybyington 5 років тому +5

      I feel like that is a Cards Against Humanity card with “blood” filling in the blanks.

    • @asians213
      @asians213 5 років тому +14

      Blood borne?

    • @xXMrZentusXx
      @xXMrZentusXx 5 років тому +1

      You forgot "Our eyes are yet to open" but it was my first thought too ^^ Bloodborne is awesome :D

  • @MrPerreaso
    @MrPerreaso 4 роки тому +54

    it would be great if guys make a video on RH- BLOOD

    • @sidneygrosshar269
      @sidneygrosshar269 4 роки тому

      Andres piñeros They can’t because they, and nobody else, knows.

    • @heatherb812
      @heatherb812 4 роки тому

      sidney Grosshar You don’t know that.

    • @justobey1939
      @justobey1939 4 роки тому

      Heather B how do you know he doesn’t know that

    • @meajor7
      @meajor7 4 роки тому +1

      Yessss!!! B- 🙋🏻‍♀️

    • @DarkMoonDroid
      @DarkMoonDroid 4 роки тому +2

      Type O Neg

  • @toniatchison3678
    @toniatchison3678 4 роки тому +7

    Me: 3am- I can watch one more Eons episode before bed.
    4am- oh just one more....
    5am- wait, I haven't seen that one....

  • @andremoreiragraca
    @andremoreiragraca 5 років тому +18

    THE STORY OF BLOOD. Doesn't get any more metal than that!

  • @TragoudistrosMPH
    @TragoudistrosMPH 5 років тому +69

    1:17 "The evolutionary response is always fluid."
    Some writer out there (Alexa Billow) deserves a serious pat on the back :)

  • @cyruse7027
    @cyruse7027 2 роки тому +2

    This was a great video. A big thank you to the PBS Eons team!

  • @IYPITWL
    @IYPITWL 4 роки тому +77

    Acelomoths.
    Shows a picture of green beans.

  • @enli1421
    @enli1421 5 років тому +14

    Eocene park should definitely be a thing.

  • @solidoustopher
    @solidoustopher 5 років тому +6

    I was skeptical about watching this, but seeing the dude from SciShow as the narrator/educator I was so relieved.

  • @vlad260
    @vlad260 5 років тому +209

    "There's nothing informative on the internet" -everyone that doesn't watch this channel.

    • @thomasrosebrough9062
      @thomasrosebrough9062 4 роки тому +9

      Literally no one says that

    • @sujthegame
      @sujthegame 4 роки тому +7

      @@thomasrosebrough9062 some people do, but it still is very stupid to say that this is the only informative channel on the internet

    • @balashibuyeeter2704
      @balashibuyeeter2704 3 роки тому

      some old people or retards do say that.

    • @vlad260
      @vlad260 3 роки тому

      @@sujthegame when did I say this was the only informative channel on the internet and when did saracism become a lost art?

    • @vlad260
      @vlad260 3 роки тому

      @@thomasrosebrough9062 you're aware hyberboly is a thing right? 103 figured it out but you still don't get it was a joke? Wow. That's impressive. I'll eat to see if you can figure out what I actually said.

  • @CrocoduckRex
    @CrocoduckRex 3 роки тому +1

    I have blown away by the quality of these short documentaries.

    • @stewartscannell8881
      @stewartscannell8881 2 роки тому

      10/10 for presentation 1/10 for providing conjecture as fact :(

  • @mariakayed5555
    @mariakayed5555 5 років тому +19

    So I came to youtube innocently to put some ambiance music to work, and then I find this!! well, guys, it was totally worth it!!!! thanks for your videos. Can you make one about how other different systems evolved (immunity, nervous, digestive, etc.) ??

  • @awesomelyshorticles
    @awesomelyshorticles 5 років тому +118

    Finally, that one guy can stop begging.

  • @Renagade5150
    @Renagade5150 5 років тому +3

    Great video. Really enjoyed this one Eons. Keep up the good work!

  • @MikeS29
    @MikeS29 4 роки тому +1

    I cannot get enough of these videos from Eons

  • @thunder_2124
    @thunder_2124 5 років тому +81

    Stumbled upon this video early without notification squad.

  • @ellenengle2767
    @ellenengle2767 5 років тому +34

    I'd love to see a video about how fossils form. Specifically, how long after something dies does it become a fossil? And how does the fossilization process work? You guys are awesome!

    • @MasterJedi86
      @MasterJedi86 5 років тому +1

      Yes! This is what I want to see.

    • @miguelpadeiro762
      @miguelpadeiro762 5 років тому +1

      When an animal dies on a surface like mud and has their remains covered by sediments to protect them from erosion, their bones and other hard body parts turn into inorganic matter, becoming fossils, you pretty much just need to have your bones protected from erosion underground and you become a fossil

    • @ellenengle2767
      @ellenengle2767 5 років тому

      @@jameskohl7959 An interesting read. Thanks for sharing!

    • @ellenengle2767
      @ellenengle2767 5 років тому

      @@miguelpadeiro762 Yes! I knew all of that. I'd like to see them make a video about everything you said, but in more detail! 😁

    • @miguelpadeiro762
      @miguelpadeiro762 5 років тому

      @@ellenengle2767 Then people dig it out and claim to be devil's work, that's all you need to know

  • @sophienugre4161
    @sophienugre4161 5 років тому +16

    That was very informative! Thank you for making this! Can you make a similar video for the evolution of thee immune system?

  • @cammiller649
    @cammiller649 4 роки тому

    Eons and Space-Time are the best things on UA-cam. Thanks PBS.

  • @lucrativelepton
    @lucrativelepton 5 років тому +7

    I find it so fascinating how we can learn so much about history just by studying the genetics.
    I would love to see an episode on how that works!

  • @Masharulzz
    @Masharulzz 5 років тому +113

    We need a video on ancestors of giraffes!

    • @antoniodunbar1643
      @antoniodunbar1643 4 роки тому +1

      Paracers

    • @aminebenz1411
      @aminebenz1411 4 роки тому +1

      Camels

    • @skyem5250
      @skyem5250 4 роки тому +4

      Giraffes diverged from camels ~50Mya and are thought to have evolved the pacing gait (moving both legs on the same side at once) convergently.

  • @rossdiggle
    @rossdiggle 4 роки тому +2

    This was the best episode yet

  • @francescathonaoostland8450
    @francescathonaoostland8450 5 років тому +1

    Thank you! I hope you make more videos of this kind. When I was a student, I did not like to study proteins... until I learned about the evolution of proteins. From that moment I found it interesting. I hope you do more like this.

  • @samsatroncoso8249
    @samsatroncoso8249 5 років тому +6

    This is so flipping cool!!! Thank you Eons for making this video! I lost my mind with the hemocyanin bit, and had to pause the video to tell everyone in my family about it! Thank you again for this amazing video!

  • @Mrtheunnameable
    @Mrtheunnameable 5 років тому +3

    Thank you. That was like the most educational 10 minutes I've had in a while.

  • @kennyupchurch
    @kennyupchurch Рік тому +3

    We love you Hank we stand beside of you. You will bet this❤❤❤

  • @crustycobs2669
    @crustycobs2669 5 років тому +1

    Thank you for your explanatory video. Fascinating. Great Paleobiology lesson

  • @camiloiribarren1450
    @camiloiribarren1450 5 років тому +22

    This is how we became the mutants we are now. Without the comic book superpowers

  • @thecreature7608
    @thecreature7608 5 років тому +33

    This has probably been requested more than anything else on the channel and for as long as I can remember this channel being a thing. So glad you finally made the video😁👍
    Also, on a complete sidenote: I've been wondering lately, if on say an alien planet animals there evolved eyes with a type of photoreceptor cell that did the job of both rods and cones in one, would they see colour clearly in the dark? Would their view of the world at night be just like the day, just like our night or would they perhaps see in slightly muted colours during night time(because of less light reacting with the photoreceptor cells etc.)? Would nocturnal eyes be much or any different from non-nocturnal eyes? Would their sleep cycles be dictated by night and day and the rotation of their planet? Would day and night time really exist for them in a prominent way?
    I haven't really been able to come up with a conclusive answer but am leaning towards the muted colours one, but I'm completely prepared to be wrong. Any thoughts?(and thanks for taking the time to read this btw)
    Extra sidenote: I think videos on the evolution of crocodilomorphs like kaprosuchus would be interesting or something about bat evolution.😁

    • @fobusas
      @fobusas 5 років тому

      Can it actually be combined? I don't know anything about this subject, but I imagine there could be mutually exclusive physical parameters that don't let a cell be both a rod and a cone?

  • @dianayates9483
    @dianayates9483 Рік тому +19

    Would love it if you would do a comparison of hemoglobin and chlorophyll. It's so interesting that they evolved to capture complementary parts of the visual spectrum but are so similar.

  • @lucascaros5298
    @lucascaros5298 5 років тому +1

    Normally theses type of educational video make sense to me but this episode is just going right over my head

  • @cruzalan003
    @cruzalan003 5 років тому +40

    They finally did it!!

  • @falnica
    @falnica 5 років тому +48

    how did senses evolve?

    • @mobilegamingfx4354
      @mobilegamingfx4354 5 років тому +4

      My guess, natural selection.
      Need to find predators or prey, eyes. Eyes don't work? Death
      Need to hear predator or prey? Ears. Ears don't work? Death
      Need to smell predator or prey? Nose. Nose don't work? Death

    • @diegobert4033
      @diegobert4033 5 років тому +3

      Read up on Itzak Bentov model of consciousness and the nervous system

    • @adeshpoz1167
      @adeshpoz1167 5 років тому

      @@mobilegamingfx4354 Except that this would be a super oversimplification of the actual process, you're kind of right.

  • @Brasswatchman
    @Brasswatchman 9 місяців тому

    Absolutely fascinating. Thank you!

  • @lizneilson5751
    @lizneilson5751 5 років тому +4

    Love this guy could listen to him all day👍

  • @ZachMorris9224
    @ZachMorris9224 5 років тому +6

    Thank you! This is fascinating! The entire channel is amazing, thank you!

    • @jonboshears
      @jonboshears 4 роки тому

      Have you talked to Slater lately Preppy?

  • @lwazishangase331
    @lwazishangase331 5 років тому +39

    If ever, you ask yourself the question: Am I spending too much time on the net?
    Remember that you watched this, to completion.

  • @philippl.2766
    @philippl.2766 5 років тому +1

    I love how amazed he looks at 9:25. He is truly amazed about how awesome nature and evolution is.

  • @tedbear6083
    @tedbear6083 Рік тому +1

    This is a fascinating summary of a ton of science and history. Brilliant!

  • @jcortese3300
    @jcortese3300 5 років тому +3

    I love when you answer amazing questions that I didn't know I was dying to ask until I watched the video. :-)

  • @peapie5920
    @peapie5920 5 років тому +5

    Cool! I love the EONS series! Learn something new every episode!

    • @123hypes
      @123hypes 5 років тому

      truth sista!!

  • @ezramarmot3350
    @ezramarmot3350 3 роки тому +7

    Can you do a video on where skeletal structures came from, like how we went from weird squid like things to having skeletons, please please I’d be fascinated

  • @sameyer716
    @sameyer716 5 років тому +5

    You guys should do a video on the unique fossils from the Burgess Shale. I remember seeing some of them in a zoology class back in high school and they fascinated me because they were just so crazy looking.

  • @RiggingDoctor
    @RiggingDoctor 5 років тому +7

    Thanks Hank for this deep dive into the least apparent type of connective tissue.

  • @traceursebas
    @traceursebas 5 років тому +4

    Thank you so much for doing requested subjects! Could you please do a video on pterosaurs origins?

  • @annak9646
    @annak9646 3 роки тому +1

    This video has actually helped me get over my fear of blood, thank you! Knowledge is always the key to overcome your fear

  • @theredhunter4997
    @theredhunter4997 Рік тому

    Really cool video, I haven’t really thought of blood evolving before but it was really cool how the process happened over time

  • @nathanphillips7787
    @nathanphillips7787 5 років тому +3

    I would love to see an episode on the protostome/deuterostome split! It was an important milestone in animal evolution that is rarely mentioned.

  • @baxterellard9320
    @baxterellard9320 5 років тому +6

    Continuing with the topic of the evolution of organs, can you do a video on the evolution of the eye and the diversity of eyes? I would love to learn about what the first eyes were like and why animals have evolved to have different kinds of eyes, such as goats with their rectangular pupils. Awesome video as always, thank you!!

  • @sarahlynn4798
    @sarahlynn4798 3 роки тому +1

    this is my favorite channel & this was such a cool video! i never knew about purple or white blood!

  • @vladlock
    @vladlock 4 роки тому

    Kudos for posting references, thanks a lot!