The Mystery Behind the Biggest Bears of All Time

  • Published: 24 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

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Comments • 1 205

  • oicram1
    oicram1  14 hours back

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

    • oicram1
      oicram1  14 hours back

      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.

      • Brad Dibble
        Brad Dibble  1 days back

        Interesting thank you

        • ntrovRT Hemi
          ntrovRT Hemi  2 days back

          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 days back

            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.

            • The Wanderer
              The Wanderer  2 days back

              um... hang on just to interject at 35 seconds... for real most bears even to this day are still mostly herbivores who take protein pills once in a while. but seriously most bears just eat plants and berries.

              • Jeremey Slayton
                Jeremey Slayton  3 days back

                The host is hot!

                • Djago
                  Djago  3 days back

                  i bet humans hunted them to extinction

                  • Toyuzu
                    Toyuzu  4 days back

                    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  5 days back

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

                      • mr spring
                        mr spring  6 days back

                        I know im late but do an evolution of ants

                        • Nicolas Plantiko
                          Nicolas Plantiko  7 days back

                          We probably killed many, too. They where competition.

                          • Brendan O'Neil
                            Brendan O'Neil  1 weeks back

                            What about climbing?

                            • مزفر ابرحم
                              مزفر ابرحم  1 weeks back

                              The Biggest Bear ever is Sea Bear from Bikini Bottom

                              • Kalli Mae Cooke
                                Kalli Mae Cooke  1 weeks back

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

                                • BLOOD
                                  BLOOD  1 weeks back

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

                                  • Dennet Oregon
                                    Dennet Oregon  2 weeks back

                                    Asteroid killed off all its prey.

                                    • EricTheNotSoRed
                                      EricTheNotSoRed  2 weeks back

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

                                      • Chris H
                                        Chris H  2 weeks back

                                        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  3 weeks back

                                          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  3 weeks back

                                            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  4 weeks back

                                              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  4 weeks back

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

                                                • Voltaic Fire
                                                  Voltaic Fire  1 months back

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

                                                  • Gonson Jebibeba
                                                    Gonson Jebibeba  1 months back

                                                    beeeee bopin' babehhhhhh3

                                                    • jacob Taves
                                                      jacob Taves  1 months back

                                                      Biotic boi

                                                      • William Perry
                                                        William Perry  1 months back

                                                        I bet Conway Twitty would have like her in those tight fitting jeans.

                                                        • todd goslin
                                                          todd goslin  1 months back

                                                          The extinction event I think she's looking for is known as the Goldilocks epoch!

                                                          • Ash Peeler
                                                            Ash Peeler  1 months back

                                                            I’m watching this while I’m in a cabin😖

                                                            • liam redmill
                                                              liam redmill  1 months back

                                                              It's body shape with slender legs, reminds me of a hyena, is it possible that,totally dominating america, some bears, developed pack traits, I can't imagine a bear of any size, taking down a bison, but a small pack, working the rear, could, please tell me what you think of my hypothesis/idea, thanks so much for your exellent educational content, and superb presentation, and oration

                                                              • Juan Manuel Saenz Kotyk
                                                                Juan Manuel Saenz Kotyk  2 months back

                                                                "history of ants" pleasee

                                                                • Daggerman105 -
                                                                  Daggerman105 -  2 months back

                                                                  Why does everyone instantly blame humans for the extinction of everything?

                                                                  Yes, we are very dangerous but no 10,000 years ago we didn’t have the real capability to nearly instantly decimate an entire ecosystem, it’s just unfeasible.

                                                                  • J Chan Tack
                                                                    J Chan Tack  2 months back

                                                                    Why did they die out?
                                                                    Me: We ate them

                                                                    • Joel Williams
                                                                      Joel Williams  2 months back

                                                                      Bear Down!

                                                                      • Derk L
                                                                        Derk L  2 months back

                                                                        Great video! Sexy, informative,

                                                                        • Terry Robinson
                                                                          Terry Robinson  2 months back

                                                                          I would like to see a show on ice age. I'd like it to be more on the southern hemisphere not Europe Asia and North America. Since both have ice

                                                                          • Roosevelt Brentwood
                                                                            Roosevelt Brentwood  2 months back

                                                                            couldn’t watch, the narrator is annoyingly perky.

                                                                            • doctim111
                                                                              doctim111  2 months back

                                                                              It is suspected that an archaic, ice-age polar bear is still roaming the Himalayas.....

                                                                              • Christopher Beebe
                                                                                Christopher Beebe  2 months back

                                                                                Bears still to this day fight any predator, polar bears and grizzly bears are the scariest predators to be face two face with on foot, sure tigers lions and such WILL kill you, bears are scarier to me.

                                                                                • Christopher Beebe
                                                                                  Christopher Beebe  2 months back

                                                                                  Umm a polar bear at the museum in DC was over a ton, 2300 lbs, on hinde legs it can look a elephant in the eye. Polar bears are HUGE and its getting down played.. wonder why. (I believe it has 18 feet tall on 2 legs)

                                                                                  • Dipstikk
                                                                                    Dipstikk  2 months back

                                                                                    Plionarctos just chillin
                                                                                    early man be like "oh dang a bear" and he all like "whoa dude where at"

                                                                                    • Rams495
                                                                                      Rams495  2 months back

                                                                                      The big bears were probably killed off by the same thing that killed half of the animals at the end of the last ice age, a huge impact. The evidence for it continues to mount but main stream science will not acknowledge it even when a gigantic crater was found in Greenland. It dates to 12kyrs ago which is precisely the time, that those that were called pseudo-scientists had theorized. I suppose we'll have to wait until this crop of scientists, that have staked their careers on the current belief system, die off and new ones that hope to make new discoveries come to the forefront.

                                                                                    • Nat Wolins
                                                                                      Nat Wolins  2 months back

                                                                                      Human are death on two legs. Human appear large mammals disappear.

                                                                                      • Jorge Martí
                                                                                        Jorge Martí  2 months back

                                                                                        Love this

                                                                                        • ScreenTalker DotOrg
                                                                                          ScreenTalker DotOrg  2 months back

                                                                                          Atlanteans wiped out the short faced bear with their laser wrist weapons

                                                                                          • Jari Tapani Ruusupuu
                                                                                            Jari Tapani Ruusupuu  2 months back

                                                                                            Maybe short-faced bears had smaller brain capasity than todays bears?

                                                                                            • Ya tú sabes Neta que sabe

                                                                                              Aunque sea por biogenetica debemos recuperar ejemplares de aquella mega fauna tan fascinante 🌝🌝🌝😇😛

                                                                                              • Kairi Suzuki
                                                                                                Kairi Suzuki  2 months back

                                                                                                Bears🐻 are versatile “Carnivora” beasts that can adapt to several niches (unlike cats or dogs!).

                                                                                                I have no idea how North American short-faced bears would have been driven to extinction by the contenpotaries🤔