The Mystery Behind the Biggest Bears of All Time

  • Published on: 23 April 2019
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    The short-faced bears turned out to be remarkably adaptable, undergoing radical changes to meet the demands of two changing continents. And yet, for reasons we don’t quite understand, their adaptability wasn’t enough to keep them from going extinct.   

    Thanks to Fabrizio De Rossi and Studio 252mya for the Arctodus and Arctotherium illustrations. You can find more of their work here:

    And thanks to Ceri Thomas for the Plionarctos and Arctotherium reconstructions! Check out more of Ceri's paleoart at and

    Produced in collaboration with PBS Digital Studios:

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  • Runtime : 11:16
  • dinosaurs dinos paleo paleontology scishow eons pbs pbs digital studios hank green john green complexly fossils natural history Bears spectacled bear Arctodus simus short-faced bears Pleistocene Epoch Arctotherium angustidens Arctotherium Arctodus North America South America Great American Biotic Interchange Smilodon Prey jaguar cougar dire wolf hypercarnivore kleptoparasitism


  • AT-MC
    AT-MC   1 days ago

    I hate to be inappropriate but, schwiiiing

  • Duncan
    Duncan   1 days ago

    I can barely bear the thought of that bear bearing down on me.

  • Shill for Science
    Shill for Science   3 days ago

    see, I woulda named them "derptotherium"because they derpy lookin.

  • Ken Hall
    Ken Hall   3 days ago

    not a single mention of Yogi or Smokey,, you've lost any shred of credibility.

  • kraigthorne
    kraigthorne   3 days ago

    1:30 The Short-faced Bear of North America was taller with a large specimen standing up to 11–12 feet (3.4–3.7 m) tall with a 14-foot (4.3 m) vertical arm reach.

  • Fredrik Dunge
    Fredrik Dunge   3 days ago

    10:00 10.000 years ago? Wouldn't that roughly coincide with the arrival of humans in the Americas?

  • truthseeker215
    truthseeker215   3 days ago

    So would the short face beat have crossed paths with the grizzly ?

  • Yogan Barrientos
    Yogan Barrientos   1 weeks ago

    It would be a cool if there was a video game that covered all of these type of old species in all of these videos.

  • Moof Cabbage
    Moof Cabbage   1 weeks ago

    It's a shame that no bears are native to Africa anymore, I would personally love to see how a bear would interact with African wildlife.

  • Jaim Deines
    Jaim Deines   1 weeks ago

    So many mysteries,So many conclusions to MEATSo many theories to PLANTI can't BEAR to SCAVENGE Any more knowledge.

  • jaxxstraw
    jaxxstraw   1 weeks ago

    I want to see more Triassic. It needs love.

  • Jesko Parra
    Jesko Parra   2 weeks ago

    Why are their bones not on display in N.A. museums? I've visited museums from various states from coast to coast, and this commonly large apex predator is never featured. #sloth #bummer

  • Denzel Fortune
    Denzel Fortune   2 weeks ago

    Didn't even know there were bears in South America. Mind blown

  • richard murphy
    richard murphy   2 weeks ago

    Specialist doesn't pay off in the long run not fussy best option

  • oicram1
    oicram1   2 weeks ago

    PS I love her badge. I have several National Parks badges......nature.

  • oicram1
    oicram1   2 weeks ago

    I love this series!!!!! But sometimes.....I wish it was me narrating. She is amazing.....but I have a great voice for documentaries. Take care, Morgan Freeman.

  • ntrovRT Hemi
    ntrovRT Hemi   2 weeks ago

    Imagine a cartel thinking they're being badass by throwing some rat in a chamber with a LITERAL teddy bear

  • Wasa Bista
    Wasa Bista   2 weeks ago

    There was a major extinction event in and around the Younger Dryas, caused by a comet shower that hit the North American glacier and triggered worldwide floods. That may be what did for the giant North American bears.

  • Djago
    Djago   2 weeks ago

    i bet humans hunted them to extinction

  • Toyuzu
    Toyuzu   2 weeks ago

    Science will tell you the largest bears currently living are Polar Bears. Not true. Alaska has coastal brown bears that make the largest Polar bears look like cubs.

  • ronaldo Duran
    ronaldo Duran   3 weeks ago

    I love Bears. They are so adorable at any age. They are so fluffy!

  • mr spring
    mr spring   3 weeks ago

    I know im late but do an evolution of ants

  • Kalli Mae Cooke
    Kalli Mae Cooke   3 weeks ago

    This channel is the only thing getting me throught the flu rn

    BLOOD   3 weeks ago

    Tsss! We all know humans killd them off duhh!!

  • EricTheNotSoRed
    EricTheNotSoRed   3 weeks ago

    Regardless its normal diet, I would not want to meet one in a dark ally.

  • Chris H
    Chris H   1 months ago

    Could the arrival of (also omniverous) humans with hunting weapons not have occupied the same niche (but far more efficiently) as them, therefore causing an abrupt end to them in the fossil record?

  • Fulcrum Indicate
    Fulcrum Indicate   1 months ago

    When you realize 1:33 they are saying the biggest bear of all time is the same size as a large Kodiac or Polar bear alive today not record-breaking just big examples.

  • Raptorialis11
    Raptorialis11   1 months ago

    I love natural history and glad to have found this channel. And Kallie is a fantastic host!! She's very enthusiastic about this.

  • Jeff Glenn
    Jeff Glenn   1 months ago

    Apparently you have not heard of a bear it lives up north it can achieve 13 ft tall it's called the polar bear

  • garrisp
    garrisp   1 months ago

    Saying “full grown person” is assuming someone’s height and is demeaning to those who are vertically challenged 😡🤬👎🏻

  • Voltaic Fire
    Voltaic Fire   1 months ago

    That short-faced bear looks unnervingly like a spider/bear hybrid to me. 😱