How Did Dinosaurs Get So Huge?

  • Publicado el 2 oct 2017
  • Part of why we’re so fascinated with extinct dinosaurs it’s just hard for us to believe that animals that huge actually existed. And yet, they existed! From the Jurassic to the Cretaceous Periods, creatures as tall as a five-story building were shaking the Earth.
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  • Ciencia y tecnologíaCiencia y tecnología

Comentarios • 1 801

  • Elvira Lover 1
    Elvira Lover 1 Hace 41 un minuto

    All is as the force Wills it.

  • Matthew Eso
    Matthew Eso Hace 6 horas

    Nothing about the oxygen rich environment ?

  • Carl Dimayuga
    Carl Dimayuga Hace 21 un hora

    Just a reminder that Hank called birds dinosaurs
    And that is awesome, because it’s true

    ALIMMOTO Hace un día

    Or maybe there was more oxygen levels back then

  • Marc Dezaire
    Marc Dezaire Hace un día

    Three reasons why we like dinosaurs : they are very large, very dangerous and very dead.

  • Marc Dezaire
    Marc Dezaire Hace un día

    Another thing I read about is that the atmospheric pressure was higher in the time of the dinos, about 150% of what we consider normal. The oxygen content was also higher, can't remember the exact figure it might have been 33%. Surely that must have given them quite an energy boost -- for all kinds of life.

  • david helm
    david helm Hace un día

    Because they et all the pies.

  • Alexandro Hutt
    Alexandro Hutt Hace un día

    Didn't atmospheric pressure also play a huge part in their size?

  • AL
    AL Hace 3 días

    Years ago, I watched a documentary and one of theories was that Earth had 20% more oxygen when Dinasours were still alive than today.

  • nicholas kloster
    nicholas kloster Hace 3 días

    How big were Dinosaur’s poop?

  • FunBotan
    FunBotan Hace 4 días

    Biological supercharger coupled with lightened structure... Strange they didn't *start* as flyers.

  • Lonnie Andrus
    Lonnie Andrus Hace 4 días

    What about oxygen levels? I've seen many theories that oxygen was much higher and allowed more efficient energy use

  • Ken Rik
    Ken Rik Hace 4 días

    The Earth did not tilt on its axis and the atmosphere was richer in oxygen, resulting in temperature climates and year-round growing seasons. The flora and fauna grew to enormous sizes, providing enough food for the dinosaurs.

  • AgAug Gaming
    AgAug Gaming Hace 4 días

    On my opinion I think because of Eating a lot or maybe the moon well moon was closer million years ago.So it stretches their body because of gravity.

  • Lemon
    Lemon Hace 5 días

    Their size was an advantage they roamed the earth for hundrets of millions of years

  • Brad Cannon
    Brad Cannon Hace 5 días

    I love you're channel and think you guys are doing an awesome job. I would like to see more videos that focus on the microbiological world such as viruses and germs.

  • MrMrannoying
    MrMrannoying Hace 6 días

    I remember hearing on some documentary that their size had something to do with how rich the air was with oxygen. Has that been researched further since i first heard it?

  • Bob Zuhlke
    Bob Zuhlke Hace 6 días

    Dinosaurs lived in a very oxygen rich environment, too.

  • Gabriel Moline
    Gabriel Moline Hace 6 días


  • maxiydeiaparatodos
    maxiydeiaparatodos Hace 7 días

    No way Hank is 2m tall!

  • Little Reuby
    Little Reuby Hace 7 días

    Must have been high amounts of oxygen in the atmosphere

  • Catwow
    Catwow Hace 7 días

    You forgot to mention that gravity wasn't as strong back then.

  • Martin M. Meiss
    Martin M. Meiss Hace 7 días

    I don't see why you make the assumption that large mammals must necessarily have large babies. If there were some survival advantage to it, natural selection could have selected for their having lots of little babies with short gestational period. Also, even if it does take two years do gestate a big mammal, that doesn't mean that the baby has to stop growing when it reaches a certain size. I think you had better strike the whole gestation thing from your list of possible factors limiting size of mammals.

  • Omri Goldshtrom
    Omri Goldshtrom Hace 7 días

    Great topic and great discussions. I was waiting to hear about the environment at the time - e.g. warmer climate, more CO2, more abundant flora to feed on, etc. Follow up video?

  • sam johnson
    sam johnson Hace 7 días

    Hank, this isn’t sci show

  • clear21light
    clear21light Hace 7 días

    The Great Extinctions book by Norman MacLeod suggests that extinction is not proof that species were poorly adapted (because 1. extinction is normal, 2. catastrophic extinctions are combination of multiple factors not just weakness of a species), and also the book suggests that animals get bigger / more specialized during times of stability & good conditions, and smaller size species flourish during times of instability & poorer conditions. So there's no scientific reason behind saying 'bigger isn't always better.' Big and small come and go. Just saying, for your interest.

  • OompaLUL
    OompaLUL Hace 7 días

    There is a dino which is long 58mt long

  • Seung Choe
    Seung Choe Hace 8 días

    How did specialization in certain type of feeding evolved on Earth? It's cool to see whales with plates for teeth that filter plankton. But how did it evolve from it's cousins that evolve to hunt?

  • Pascal Jaeger
    Pascal Jaeger Hace 9 días

    145 metric tons or 47‘436“ Stones of the US Land Measuring Bureau in the Imperial System, but only when measured in US Mainland, Alaska and the Death Star, except Wyoming. In Hawaii and Wyoming weight is measured in Bliggits which is the weight of the Presidents toe at Midnight.

  • Teddy
    Teddy Hace 9 días

    Got a Jurassic world add

  • Huell Babineaux
    Huell Babineaux Hace 9 días

    Sauropods = 4 legs
    Theropods = 2 legs
    I don't think it's that simple...

  • Cush
    Cush Hace 10 días

    They ate a lot.

  • Luong Do
    Luong Do Hace 10 días

    Possibly a type of food source like an extinct plant

  • James Gundlach
    James Gundlach Hace 11 días

    They're only dead through no fault of evolution. Pretty hard for anything to really survive an apocalyptic extinction event. Sure, smaller things survived, but they just got lucky and were able to adapt better. I think it's dishonest to claim being so large was evolutionarily bad considering large animals lived on this earth much longer than the sizes we're used to today.

  • Jake Stockton
    Jake Stockton Hace 13 días

    If you took all sizes in comparison, (from the Planck length to the observable universe), bacteria fall in the middle. If we look at our size in the grand scheme of things, we're on the larger side of that spectrum. Especially considering that we're closer in size to a blue whale than a bacterium.

  • Michael Sanchez
    Michael Sanchez Hace 13 días

    Oh! I know this one it has to do with the o2, and co2, and nitrogen in the air the mixture was different.

  • Lando Q
    Lando Q Hace 13 días

    Not as much as an advantage to them but to earth's biological refinement which will eventually benefit plant and animal species that inhabit the planet today millions of years later including us.

  • Steve Smith
    Steve Smith Hace 14 días

    is this a thing now? calling them non-avian dinosaurs

  • Ambition
    Ambition Hace 14 días

    More oxygen right?

  • Musketeer009
    Musketeer009 Hace 15 días

    You didn't mention that Sauritian size may have been down to their food 'choice'. Having to eat masses of low nutrition vegetable matter required an 'efficiant' digestive system, which required large amounts of the food matter to be broken down in large and possibly multiple stomachs. This in itself would then require a bigger body to heft all that extra weight around.
    Also, if these creatures migrated, it is possible that huge reseves of food were needed to be stored somewhere, in case their migration route took them through sparsly vegetated areas. This may have also been helped by their relatively low metabolic rate (compared to modern mamals and avian dinosaurs)

  • Betta Forever
    Betta Forever Hace 15 días +1

    I'd love to see a video on Human evolution!

  • Colin Silver
    Colin Silver Hace 15 días

    I can only imagine them growing that large because food was abundant and large also. Everything was plentiful back then. The only think plentiful now are tweets.

  • FishyYT
    FishyYT Hace 15 días

    Lizards aren't related to dinosaurs? Only birds? That's why there's no bird and lizard hybrid looking thing

    • Steve Smith
      Steve Smith Hace 14 días

      well back then there were plenty of non dinosaur lizards. I'll take a wild guess and say that modern day lizards are descended from those creatures, and not Dinosaurs.

  • The Civilian Sentinel
    The Civilian Sentinel Hace 15 días

    that really answered nothing at all. thanks.

  • kez kezooie
    kez kezooie Hace 15 días

    What is the current thinking on homeothermia in dinosaurs and when and in what group/s of creatures is it thought possible that homeothermia first began developing?

  • Artonline
    Artonline Hace 16 días

    The government hacked my account with a fully upgraded war ostrich... What kind of person steals a mans war ostrich

  • Damon Hicks
    Damon Hicks Hace 16 días

    So you're saying, giant dinosaurs were bigger and had hollow bones, but mammals can't get too big because our bones can't support the weight; even though we have solid hard bones and dinos have hollow ones? That doesn't make sense.

  • Harry Kiralfy Broe
    Harry Kiralfy Broe Hace 17 días

    Air - A very creative solution, by nature, yet obvious when you think about it.

  • PtolemyJones
    PtolemyJones Hace 17 días

    Seems oddly worded, isn't the how obvious? The why seems more interesting...

  • 4Gunner
    4Gunner Hace 17 días

    Can you do a video on bees and call it Bee Movie 2?

  • Jintaro Kensei
    Jintaro Kensei Hace 18 días

    More oxigen.

  • Mike F
    Mike F Hace 18 días

    I guess you could say it's a....SAUR...subject. Saur. Because...the name, you see...

  • Mervin Martinez
    Mervin Martinez Hace 19 días

    Could the percentage of oxygen in the atmosphere also have played a roll on the size of the dinosaurs? It is believed that giant insects in those times benefited from the higher amount of oxygen in the atmosphere since apparently it was easier for them to breathe in the oxygen, but I know that their breathing was different from the dinosaurs

    • Mervin Martinez
      Mervin Martinez Hace 17 días

      B Xx, well you seem like a well informed individual, so informed that it can even explain his own answer....

    • B Xx
      B Xx Hace 17 días

      Nope. Quit asking stupid questions Merv

  • Stephen Castro
    Stephen Castro Hace 19 días

    BTW, could you do some videos about these creatures?
    4.Marine Reptiles

  • Stephen Castro
    Stephen Castro Hace 19 días

    Some paleontologists said that the growth of giant dinosaurs had to do with the warm climate during the Jurassic and Cretaceous. The warm climate means that dinosaurs did not need to eat much to be energized. They rely more on the warm climate to stay warm and energized. With that said, the food they consumed could be used with to something else other than energy. The food could be used for growth instead.

  • Gustavo Muñoz Peluche
    Gustavo Muñoz Peluche Hace 20 días

    There was more oxygen back then.

  • Super S God
    Super S God Hace 20 días

    May be there was a lot more oxygen in the air back then?
    Dinosaurs weren't the only ones that grew to be massive.
    Insects were also bigger all the way back then.

  • Solan K
    Solan K Hace 20 días

    Video should’ve mentioned how in the era when dinosaurs got really big, it is estimated that oxygen levels were much higher. Insects used to be huge too.
    And clearly size was some sort of advantage, or so many of them wouldn’t have gotten so big.

  • evnickols
    evnickols Hace 21 un día

    Whey protein and the 5x5 strength program, no cardio

  • Chip
    Chip Hace 21 un día

    but did they lift?

  • Ari Zadok
    Ari Zadok Hace 22 días

    How do we know that the various sauropod specimens of various sizes represent different species, rather than differently sized members of the same species? What is the difference between an apatosaurus and a supersaurus, for example, and how do we know they couldn't produce viable offspring?

  • Benjamin Brewer
    Benjamin Brewer Hace 23 días

    Probably some dinosaurs never stopped growing like crocodiles.

  • Sean Coyne
    Sean Coyne Hace 23 días

    What about atmospheric O2 content. Did a higher concentration of oxygen play any role in gargantuanism?

  • Limmeh
    Limmeh Hace 23 días

    I watched the giant insect video and it talked about increased oxygen levels in the atmosphere.. Maybe this affected the dinosaurs too?

  • agenttexx
    agenttexx Hace 23 días

    The animals were bigger because gravity was lower.

  • Jack the lad
    Jack the lad Hace 23 días

    They played Mario games and invented the mushrooms that helped Mario get big

  • BAD TV
    BAD TV Hace 23 días

    Tree where larger they needed the height to reach them to eat.

  • BAD TV
    BAD TV Hace 23 días

    They where so large because there was more oxygen on earth and there lungs “pockets” evolved to process more air making their size reasonable at that time.

  • Abcde
    Abcde Hace 24 días

    This just in......the air sacks were full of helium

  • Dan Marsh
    Dan Marsh Hace 24 días +1

    So... the answer is "I dunno?" Really?

  • Seraphim Serenata
    Seraphim Serenata Hace 25 días

    the atmosphere was thick with oxygen

  • Atlanntis
    Atlanntis Hace 25 días

    Saying they suck because they are gigantic is easy, you'd be extinct too had I thrown a couple meteors in your face

  • joelouis
    joelouis Hace 25 días

    I thought it was a greater oxygen content in the atmosphere

  • isac mamede
    isac mamede Hace 25 días

    I think maybe there’s some connection with the porcentagem of oxygen on that time. There’s more oxygen in the water then in the air...

  • Antares
    Antares Hace 27 días

    I've always wondered how the baby sauropods looked like. I imagine they were terribly cute :)

  • 411STRYKERT1
    411STRYKERT1 Hace 27 días

    I have read somewhere about the atmosphere was the reason for there size

  • Paul Verbruggen
    Paul Verbruggen Hace 27 días

    I always believed that the amount of oxygen had a big influence on the size of the dinos

  • kashem58
    kashem58 Hace 27 días

    all the dinos were on steriods

  • sanket kumar
    sanket kumar Hace 28 días

    Sir,a question!!
    You told as dinosaurs birds have a similar air sac so why they didn't become as humongous as dinosaurs?

  • smallbluemachine
    smallbluemachine Hace 28 días

    Fascinating, thank you.

  • mcrx604
    mcrx604 Hace 28 días

    More plant videos!!!

  • Brandon Cosmo
    Brandon Cosmo Hace 28 días

    I thought sharks and crocodiles were dinosaurs?

  • Brent
    Brent Hace 29 días

    I wouldn't really say they were at an evolutionary disadvantage just because they aren't here now. A massive asteroid impact isn't really a fair litmus test.

  • Pablo Matamoros
    Pablo Matamoros Hace 29 días

    Years ago the theory was that they were so big to help them regulate their temperature. The bigger you are, the less energy you need keep you warm and with high temperature.

  • ali aman
    ali aman Hace 29 días

    Gravity on earth was different

  • Michael Reynolds
    Michael Reynolds Hace 29 días

    doesn't it also have to do with the O2 content in the air? i heard this was why insects at that time were also huge.

  • Barbara Thomascall
    Barbara Thomascall Hace 29 días

    The megafauna of the Miocene and Oligocene; Naked mole-rats, descent of, relatives of; more flora of the times the series discusses

  • eniahs T
    eniahs T Hace 29 días

    Maybe because of the atmosphere back then? Because of the oxygen level)

  • Hackarma
    Hackarma Hace 29 días

    All your videos are awesome but there somthing I think is off in this one. You say bigger isn't better, and I would say okay but to prove it you they "they're gone". It is true, their massive needs led them to death but the same scheme apply to all animals bigger than, erh I don't really know, maybe a rabbit, during such a great crisis as KT extinction.
    In fact, those dinosaurs spread around the world from 150 Million years ago to the KT extinction, so their size was an advantage.
    Sorry for errors if there is some, I'm still learning.

  • Georgio Edson
    Georgio Edson Hace 29 días +1

    Dude the answer is easy : GRAVITY , the gravity wasn't the same before, at dinosaurs time gravity was lower than today's gravity that's all ...

    • Marcel Oliver
      Marcel Oliver Hace 6 días +1

      I am detecting some sarcasm in here, but it's YT so I'll point out that this wasn't the case. xD

  • Eric Chamberlain
    Eric Chamberlain Hace un mes

    Synthol, which also caused their extinction.

  • George Reyes
    George Reyes Hace un mes

    We could of been taller the t rex if our air was the same from dinosaur time period

  • Adon Lando
    Adon Lando Hace un mes

    It was the higher oxygen content of the atmosphere, which allowed the reptilians to get so huge.

  • cazzie bb
    cazzie bb Hace un mes

    Oxygen content in the air was greater back then.

  • Alexey Souvorkin
    Alexey Souvorkin Hace un mes

    Dinosaurs wake me up in the mornings!

  • Ulrich Scaar
    Ulrich Scaar Hace un mes

    Would gravity not have been massively lighter? Only seems like a logical conclusion...

  • Frank Shifreen
    Frank Shifreen Hace un mes

    After seeing this again- - You have no theory- your view is very myopic- why at different times are there trends toward gigantism- Happened at times with mammals- giant sloths, elephants, etc as well as dinosaurs. Perhaps gravity was different for a time, oxygen richer. the stress of moving a large body in space is significant

  • James McDonough
    James McDonough Hace un mes

    Has there ever been anything bigger than a blue whale? Maybe there are fossils of ancient super-giant sea life hidden at the bottom of the ocean, in places too deep for us to explore.

  • Bonehead Trevor
    Bonehead Trevor Hace un mes

    How did the lip evolve.

  • Kieran Kieran
    Kieran Kieran Hace un mes +1

    may this show last for the next eons to come