How Did Dinosaurs Get So Huge?

  • Publicado el 2 oct 2017
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    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.
    Thanks to Nathan E. Rogers, Julio Lacerda, Franz Anthony and Studio 252mya for their illustrations. You can find more of their work here:
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  • Ciencia y tecnologíaCiencia y tecnología

Comentarios • 2 564

  • catheadmoon
    catheadmoon Hace un día

    greater oxygen supply (also explains the lessening sperm count of males in predominantly beef-eating countries).

  • Tantiwa Hopak
    Tantiwa Hopak Hace un día

    0:55 I like the device you are using

  • Ichsuka
    Ichsuka Hace 2 días

    Ohhh lawd they coming.

  • paul spring
    paul spring Hace 3 días

    Our ancestors were also large when the dinosaurs were really large. They all grew to gigantic proportions because of the greenhouse effect. Greenhouses are proven to grow plants better than just leaving plants out in the open. The way to grow animals to gigantic proportions is essentially the same way. You control the environment. Double the Oxygen and air pressure and EVERYTHING will grow bigger. That's the only way that dinosaurs like the Sauropods can have such small heads (and especially nostrils) compared to the rest of their bodies. As for humanity's ancestors, they were also huge. There is a lot of historical data to indicate this, from old newspaper articles (before the scientific community realized that they MUST believe in the Evolution model and squash all other options) which boldly declared that giant human skeletons were found, to the stories of the Lovelock Caves and even the dinosaur/human footprints in Glen Rose, Texas. Not to mention all the OOPARTS that are found all over the world that have no explanation. Like the various things found in coal or ancient mechanical devices found underwater. These are just a few examples. I'm fascinated with OOPARTS and have watched a LOT of videos on the subject and have looked into any and all websites and papers that I can find. What it all comes down to is that the world may not be what you might think it is. Here's one final question to consider. How why and when did the Glaciers form? Really think about it. Why does ice form at the poles? (Because when it gets really cold, it becomes magnetic, but that doesn't answer where all the ice came from or how it got so cold in the first place.)

    • Swiftbow
      Swiftbow Hace un día

      It's not the oxygen, it's the CO2. Try growing a plant with just O2 and it'll die real quick. But double the CO2? They will shock you. (Plants convert CO2 to oxygen and use the carbon to build their own cell structure during photosynthesis.)
      Also, wow... I just read the rest of your post. Um, ice forms at the poles because they get very little sunlight. (Kind of like what happens to everywhere that isn't tropical in the winter.) Even then, Earth has only had polar ice caps for relatively brief periods in our history. The Arctic cap most recently formed when the Panama Isthmus formed and cut off the Atlantic from the Pacific currents.

  • 1joshjosh1
    1joshjosh1 Hace 3 días

    I tip my hat off to hard core religious folk, the more evidence we have for how this all works and especially now DNA sequencing you have to be really freaking stubborn not to believe this continue saying the Earth is 7000 years old. I admire the head strong-ness.

  • tukaha teina
    tukaha teina Hace 3 días

    Okay listen what if earth was hit by a astroid so strong it changed the gravity on earth to.become.much strong leaving ultimit rise of mamals.and.all.the and knocked off its axsis

    • John DC
      John DC Hace 3 días

      That's pretty unlikely. If you want to change the strength of the gravity of Earth, you would need to add *a lot* more mass than the initial Yucatan meteor. If that amount of mass crashed to Earth to change its gravity, it would literally melt everything on the surface.

  • Adon hhk
    Adon hhk Hace 4 días

    Because vegan diet, eat grass, get swoll

  • Red Droid
    Red Droid Hace 5 días


  • Creeping Normalcy
    Creeping Normalcy Hace 6 días +1

    *Large Dinosaurs would probably have a hard time oxygenating their blood with our current air composition and it's low percentage of oxygen.*

    • trvth1s
      trvth1s Hace 4 días +1

      Wrong, oxygen levels today are at 21%, from the Triassic to the Cretaceous oxygen levels were between 10-15%, a lot lower then today.

  • El Emilio
    El Emilio Hace 6 días

    They never exited because evolution is a made up thing to distract people from the truth.

    • Peter Lewerin
      Peter Lewerin Hace 4 días

      Yep. The truth is that you are all simulated people in an experiment I'm running, and your world has existed for about two months, not millions of years. BTW, I'm getting ready to wrap it up soon, so remember to have fun the next couple of weeks or so before the end.

  • Ore wa ochinchin ga daisuki nandayo

    the real absolute units

  • Lazy Zim
    Lazy Zim Hace 6 días

    I thought it was pretty obvious why dinosaurs were so big. In a world of plants converting CO2 to Oxygen the oxygen content of the air was higher therefore animals could grow bigger. Just as the higher the oxygen levels the bigger an insect will grow. So in oxygen rich environments like the jungle floor we get big bugs.

    • trvth1s
      trvth1s Hace 4 días

      You're wrong, oxygen levels today are at 21%, from the Triassic to the Cretaceous oxygen levels were between 10-15%, a lot lower then today.

  • Lukeamania
    Lukeamania Hace 7 días

    I'm sure dinosaurs didn't just come into being all huge. They must have evolved from smaller versions of themselves and got larger and larger over millions of years. I wonder if "dinosaur like" (as in BIG) animals could evolve again? I suppose if they haven't in 65 million years, then if they do, it will be likely at least another 100+ million years if they were to.

    • trvth1s
      trvth1s Hace 4 días +1

      There have been plenty of big animals. Bush elephants today are huge.
      There were elephant and rhino species which were bigger then all theropoda and ornithischian dinosaurs, only a few sauropods became titans

  • Frank Dalla
    Frank Dalla Hace 7 días

    Hard to envision people 20 feet tall.... Or the size of their houses.

  • James Dooling
    James Dooling Hace 7 días

    Are there really giant skeletons in the world? Who were they?

  • Paragon Of virtue
    Paragon Of virtue Hace 8 días

    The gap of million of years between giant animals and human like creatures prove a smart design ,

    • John DC
      John DC Hace 3 días

      Nope. It just proves evolution. We have seen the ancestors of humans from the start of the Cenozoic to modern humans. It shows a clear transition, and therefore evolution.

  • DazerDeisser
    DazerDeisser Hace 8 días

    thats alotta big poops

  • anarchoutis
    anarchoutis Hace 8 días


  • beccabunny09
    beccabunny09 Hace 8 días

    Hank is 6'6?

  • maikol
    maikol Hace 8 días +1

    what about atmospheric composition. The atmosphere during the permian period was high in oxygen which allowed the development of oversized insects.

    • trvth1s
      trvth1s Hace 4 días

      Wrong, oxygen levels today are at 21%, from the Triassic to the Cretaceous oxygen levels were between 10-15%, a lot lower then today.
      Permian was tens of millions of years before dinosaurs existed, triassic dinosaurs were smaller then animals today

    • Creeping Normalcy
      Creeping Normalcy Hace 6 días

      I believe the major factor behind their size was the high atmospheric oxygen content. Large Dinosaurs would probably have a hard time oxygenating their blood with our current air composition.

  • Allan Duarte
    Allan Duarte Hace 9 días

    Yes, bigger is always better. You can't use a meteoric disaster to define being big as ineffective.

  • shadowdance4666
    shadowdance4666 Hace 10 días

    Extinction events are the driving force behind the reset button that brings about the diminishing of lifeforms. The longer a period without an extinction event the bigger the lifeforms can arrive. Enduring success leads to largeness

  • daJe313
    daJe313 Hace 10 días

    Why are u measuring in meters???

    • thatoriordanlad
      thatoriordanlad Hace 9 días

      Because it's 2019. Who measures in feet and inches anymore? Liberia, Myanmar and the USA. Metric system it is.

  • Tylr
    Tylr Hace 11 días

    your whole eggs are small therefore large animals could get larger because they come from smaller silly. I point to the kangaroo. Now explain why they can't have enormous kangaroos. Just because you have smaller young doesn't mean they can't grow large, nor does having large young mean they will grow up smaller. This makes no sense...
    also, don't elephants have something similar to these airbags in their feet?

    • trvth1s
      trvth1s Hace 4 días

      elephants have mammalian bones which are like reptile bones, full of marrow. Only birds today have hollow bones, which are stronger structurally.

      As for eggs, the issue is not the egg but the gestation period. Imagine putting a trex in Africa savannah, it will likely need to eat 1 elephant every week. After a few years elephants will be extinct since it takes elephants 18 months to have just 1 baby.
      However, triceratops, which is as big as an elephant, could have layed 7-12 eggs at a time, so bam while trex may need to eat 1 every week, they can have a lot more babies to expand the generation

  • Bimjiveli
    Bimjiveli Hace 11 días

    Didn’t know birds were dinosaurs

  • Donald Badowski
    Donald Badowski Hace 12 días

    Nice, but the biggest birds that ever lived are not ostriches. Before the rise of the mammals, flightless birds got huge, much bigger than your SUV.

    • trvth1s
      trvth1s Hace 4 días

      no not bigger then suv. Biggest birds ever were elephant birds which did not get bigger then bison. Birds have 150 million years of evolution and this is the biggest species ever.
      terror birds were relatively smaller, about as heavy as big cats

  • Jack Smith
    Jack Smith Hace 12 días

    Size and number are important situationally. If invertebrates rebelled against vertebrates we would loose, but it will never come to that.....-because they haven't got the "back bone"!(Jose Long) Ha! But bacteria? Well, we get along swimmingly.

  • Ras
    Ras Hace 13 días

    Only birds survived?
    What about lizards, snakes, crocodiles, frogs, turtles, sharks...?

    • trvth1s
      trvth1s Hace 4 días

      +Ras Some snakes [sea snake] have live young as babies, not eggs, so are they mammals?

      Frogs breathe through their skin, they are amphibians.Their eggs are also not shelled. You and me have a lot more in common with a crocodile then a crocodile has with an amphibian.
      Crocodiles are crocodilia, lizards is a very diverse group of animals. You name animals with far more evolutionary differences then mammals. They all have families who branched off millions of years before mammals, meaning they have more differences with each other then mammals have with them.

      Birds are the only existing dinosaurs today.

      This explains what makes a dinosaur a dinosaur

    • Ras
      Ras Hace 4 días

      +trvth1s But why are these not dinosaurs? The connection I'm making is, they're all (excluding sharks) hairless, neo-cortexless, egg laying reptilish bastards.
      Assuming dinosaurs were the same.

    • trvth1s
      trvth1s Hace 4 días

      those are not dinosaurs,
      also, mammals have existed for 150 million years, much older then most dinosaurs, so add mammals to the list.
      Birds were the only diinosaurs to survive

    • thatoriordanlad
      thatoriordanlad Hace 9 días

      They all share a common ancestor with birds, but it stems way before the dinosaurs.

  • Neil Óg
    Neil Óg Hace 15 días

    With atmoshperic CO2 in the Cretaceous at a staggering 2-4% there would have been more plant matter around to eat as plants are basically built from CO2 plus water. This would explain why huge size would not be such a disadavantage. Plenty of food to go around!

    • trvth1s
      trvth1s Hace 4 días

      I would add that short gestation periods allowed big animals to multiply faster and fill more niche

  • Akula A
    Akula A Hace 15 días +1

    How did Dinosaurs get to be so huge?
    They were greedy bastards

  • Patrick Palmer
    Patrick Palmer Hace 19 días

    The moon was a lot closer then and the oxygen levels were higher also

    • trvth1s
      trvth1s Hace 4 días +1

      Wrong, oxygen levels today are at 21%, from the Triassic to the Cretaceous oxygen levels were between 10-15%, a lot lower then today

  • Lil Bhaddie
    Lil Bhaddie Hace 19 días

    Sauropods was successful it took a massive extinction event to kill them off 😕

  • WÅ‚adca Wymiaru
    WÅ‚adca Wymiaru Hace 19 días +2

    There is the answer how to POWER such massive body:
    Oxygen content in atmosphere!
    High CO2 and temperature!
    Abundance of food (tropis even on Polar circle)

    • WÅ‚adca Wymiaru
      WÅ‚adca Wymiaru Hace 4 días

      I can agree only to *triassic* period when life rebuilds after permian catastrophy.
      "Your" part is contradiced by wikipedia. I will NOT believe random article.
      To power big machine you need A LOT of energy, that same about body.
      (plus BIG air intake)

    • trvth1s
      trvth1s Hace 4 días

      +WÅ‚adca Wymiaru It seems you lack basic reading comprehension.
      If you can't understand what you quoted i am not sure i will be able to help you understand, please re-read it slowly and think about what you read.

      To make it simple, it says that todays oxygen levels are 21%, but during the nonavian dinosaur era oxygen levels were 10-15%, which is lower then oxygen levels today, and a lot lower then the 30% oxygen levels previous studies suggested [meaning previous studies were wrong because now we have samples from plant material trapped in amber].

    • WÅ‚adca Wymiaru
      WÅ‚adca Wymiaru Hace 4 días

      Looks like you didn't read all:
      Based on their results, they determined that for much of the Earth's
      history dating back to the Triassic Period, oxygen levels hovered
      between 10 and 15 percent -- far below today's 21 percent *and the 30 percent previous studies suggested characterized the Cretaceous Period* , which lasted between 65-145 million years ago.

    • trvth1s
      trvth1s Hace 4 días

    • trvth1s
      trvth1s Hace 4 días

      Wrong, oxygen levels today are at 21%, from the Triassic to the Cretaceous oxygen levels were between 10-15%, a lot lower then today

  • life42theuniverse
    life42theuniverse Hace 20 días

    My hypothesis is that the planet had a different angular momentum when the dinosaurs existed. That is to say the earth was spinning faster like a large centrifuge. Everything at the surface had enough inertia that it had a slight resistance to gravity.. when the asteroid that hit the earth 65 million years ago the rate of rotation changed and only the smaller life had the inertia to stand back up.

  • The Wonderer
    The Wonderer Hace 21 un día

    That because the oxygen level was still high.

    • trvth1s
      trvth1s Hace 4 días

      Wrong, oxygen levels today are at 21%, from the Triassic to the Cretaceous oxygen levels were between 10-15%, a lot lower then today

  • Robert.Giguere
    Robert.Giguere Hace 22 días

    These air sacs in big dinosaurs means nothing in respect of weight. It’s like putting sandwiches in your pockets before to weigh yourself. It wont matters much on the scale.
    The reason why dinosaurs got so big is because the Mesozoic era was a hot house with CO2 reaching levels six times higher than today (400 ppm). CO2 is a provider of carbon for the plant during photosynthesis. The higher the levels, the better for plants… and plants are at the base of the food chain. Know that the Mesozoic mammals were not warmed blooded animals like todays’ mammals. If modern mammals would have lived during the Mesozoic, they also would have reached large sizes.

    • trvth1s
      trvth1s Hace 4 días

      airsacs made their respiratory system more advanced and far more efficient then ours, it did not help them weight more but it helped them spread oxygen to more muscles.
      Hollow bones are different from airsacs, hollow bones are stronger and better structurally then mammal.reptile bones.

      Ever wonder where the phrase ''chicken legs'' comes from? Chickens have legs that seem far too thin for even their frame, they can have these super thin legs because their bones are better then mammal bones

  • Alex Scott
    Alex Scott Hace 22 días

    All reptiles grow until they die.Dinosaurs lived much longer lives which is why some grew so massive.

  • IAmAgainst
    IAmAgainst Hace 22 días +1

    Who else wants to try some barbecued argentinosaurus?

  • FlorinSutu
    FlorinSutu Hace 23 días

    Did you notice that in most mammals, the male doesn't stay much around the female, who grows the offspring alone, while most birds make stable families, with both parents helping their chicks ?

  • Tom Ward
    Tom Ward Hace 23 días

    Escaping predators, and sexual selection. A lot of species choose to mate with large suitors. Taken to the extreme you get titanosaur.

  • amistry605
    amistry605 Hace 24 días

    Is it true that there was more oxygen in the atmosphere back then?

    • trvth1s
      trvth1s Hace 4 días

      +amistry605 There was more oxygen in the carboniferous long before the dinosaurs, during the carboniferous insects were giant.

      That guys video above has different videos of animals in different era's, he just puts the basics of course. It's like putting elephants, rhinos, lions, wolfs and bears in today era.

      I am not sure why they thought there was more, they used to think it was 30% back then, but now they tested plants trapped in amber and have been able to measure oxygen of the times.

    • amistry605
      amistry605 Hace 4 días

      +trvth1s that's an interesting article! I wonder why we learned that there was more oxygen in the atmosphere back then...

    • trvth1s
      trvth1s Hace 4 días +1

      +amistry605 yea i got that from this an interesting read

    • amistry605
      amistry605 Hace 4 días

      +trvth1s hmm... didn't know that.

    • trvth1s
      trvth1s Hace 4 días +1

      No, it was an old theory with no proof but now we know oxygen levels today are at 21%, from the Triassic to the Cretaceous oxygen levels were between 10-15%, a lot lower then today

  • Gürel Vural
    Gürel Vural Hace 24 días

    maybe the gravitational force of earth was less back then... compared to today...

  • Jon Judice
    Jon Judice Hace 25 días

    Earth is not from this system it was under a lower gravity. I'll explain because hes full of crap. You scale by a general average of cross section. We know that strength basically varies according to cross section of the bones and muscles. If you know a person's weight and you want a general average of the body cross section. Weight is going to be proportional to volume, some number times volume. You might have a weight lifting event at a bench press. You got 6-7 different weight classes. You'd like to know who had really done the best lift, overall. What you do is, divide through by 2/3 power of the athletes weight in each case and the numbers all line up they almost become the same number. One will stand out just a little bit, right, and that's going to be the guy that did the best lift. Ok now we're gonna go into the world of theory and do scaling of the same athletes different sizes. Well, that sort of isometric scaling becomes perfect, right, because you're talking about the same guy just making him different sizes. You would like to know at what size does the square-cubed law make one of these top human dysfunctional what you do is you're going to exactly use this two-thirds power of weight scaling factor. On the left side you write 1350 divided by the two-thirds power of 350, equals on the right side of the equation, just the guy lifting himself off the floor right, that's x divided by the 2/3 power of x and you'll get a number somewhere between 18000-21000 pounds. That's the maximum limit for the world, for strongest athletes we know anything about. But what's funny is the biggest elephants that we know are typically that size. What I'm getting at is earth needed to have and was under and different gravity back then. You'd need a ratio something like 2.8 to 1 less gravity for a 180 ton dinosaur to walk on the same earth as an 8 ton elephant

  • Steven Yourke
    Steven Yourke Hace 25 días

    Easy. Steroids!

  • Yoan Ulin
    Yoan Ulin Hace 25 días

    ITS dosen't extinct

  • Duc Nguyen
    Duc Nguyen Hace 25 días

    Air, water, earth, action of the sun were absolutely different millions of years ago. Richer than today to grow bigger trees and living beings. Positive vibes and thoughts 💭

  • Leather Neck
    Leather Neck Hace 25 días

    That means the humans that were alive then were huge

    • TheRublixCube
      TheRublixCube Hace 24 días

      Humans weren't alive back then, in fact they evolved pretty recently, in the last few million years, wheras non-avian dinosaurs went extinct 66 million years ago

  • Nelson Montana
    Nelson Montana Hace 25 días

    I miss the brontosaurus where the tail dragged. They were cool. Then again, all my knowledge of Dinosaurs comes from Ray Harryhausen movies.

  • chanbaekyeon is my ship
    chanbaekyeon is my ship Hace 26 días

    waittt.......Isn't he the guy on crashcourse vids too?

  • Mama Ramnunpuia
    Mama Ramnunpuia Hace 26 días

    The largest terrestrial mammal isnt paraceratherium

    • trvth1s
      trvth1s Hace 4 días

      between that, an extinct mammoth and an extinct elephant, now they think there was an elephant which was a bit bigger then the river elephant and paraceratherium, i believe it is called palaeoloxodon.
      The animal family group which includes rhinos, elephants and hippo seem to be the sauropods of mammals. Of course not as monstrous as dinosaurs but still pretty big and powerful

  • Joseph Ang
    Joseph Ang Hace 26 días

    Maybe earth was smaller and gravity was lower.
    It became bigger from material from space?

  • Andrew Armstrong
    Andrew Armstrong Hace 26 días

    They only tested plant resin no matter how stable still a theory,oxygen at 10 to 15% can’t grasp how an organism could function at such low levels and be so massive, these plant resins may have been produced at altitude .

  • David Skulski
    David Skulski Hace 26 días

    Interesting, but the narrator speaks too quickly.

  • Dora Këmba
    Dora Këmba Hace 26 días

    Supersaurus looks like a really, really, reeeeally gigantic snake ... with legs.

  • ZetaPrime 77
    ZetaPrime 77 Hace 26 días

    But what about platypuses? Could we have super massive platypuses?!

  • Jason Middleton
    Jason Middleton Hace 26 días

    How did dinosaurs get so hugh, my guess is that they were further away from the sun/heat which allowed more efficient breathing and cooler temperatures allowing them to travel for much longer distances, the rest is evolution :)

  • Gerald Nordahl
    Gerald Nordahl Hace 26 días

    Dinosaurs got big because there was no rules or regulations about how much pot that can be smoked so there was alot of pizza to be eaten and alot of Budweiser bear to be drunk.

  • MrDontCare
    MrDontCare Hace 26 días

    I saw a test of mice where they one mice the got oxygen we have today, and the other mice they gave it more oxygen. Not sure how much. But the mice that got more oxygen was way bigger. So could this be the same with the dinosaur, they had bigger and more trees to make oxygen? Just google it.

    • trvth1s
      trvth1s Hace 26 días

      +Gerald Nordahl Interesting theory, a lot of co2 back then so pot was likely stronger and more abundant, however pizza evolved during the Cenozoic unless the fossil record says otherwise.

    • Gerald Nordahl
      Gerald Nordahl Hace 26 días

      +trvth1s.they smoked 200 foot tall pot plants and ate pizza.

    • trvth1s
      trvth1s Hace 26 días

      problem is oxygen levels from the triassic to the cretaceous fluctuated between 10%-15%, today oxygen levels are a whopping 21%, so nonavian dinosaurs had less oxygen!

    • Gerald Nordahl
      Gerald Nordahl Hace 26 días

      Alot of 100 foot pot plants to be eaten.

  • Nick Komen
    Nick Komen Hace 26 días

    This is a terrible video on the explanation. I'm not a scientist but all this irrelevant information about "why" they got so big was unnecessary. I was expecting a video on thr environment of the earth due to the fact it was OXYGEN levels the reason "why"they were so big. That wasn't even mentioned. I can't believe you guys allowed this video it with that title. Terrible job

    • trvth1s
      trvth1s Hace 26 días

      They didn't mention it because oxygen levels from the triassic to the cretaceous fluctuated between 10%-15%, today oxygen levels are a whopping 21%, so nonavian dinosaurs had less oxygen! Your point is mute and outdated

  • Shawn Bailey
    Shawn Bailey Hace 26 días

    grapefruit juice!

    • Gerald Nordahl
      Gerald Nordahl Hace 26 días

      Large pot plants bigger than the redwood trees.

  • guy who has no soul
    guy who has no soul Hace 26 días


  • The Cereal Guy
    The Cereal Guy Hace 26 días

    Bigger better stronger

  • HKUriah
    HKUriah Hace 27 días

    So, how big are these things in real measurements? I don't think metric so all of the scale in this thing is meaningless to me. And probably most Americans.

  • flimflam
    flimflam Hace 27 días

    Different gravitational fields?

  • Crispy Bacon
    Crispy Bacon Hace 27 días

    I find it amazing the same adaptations enabled both the existence of super-massive dinos and for _tiny_ birds to be light enough to fly.

  • Purple Space Cow Studios
    Purple Space Cow Studios Hace 27 días

    heyyyyyy, why does youtube keep unsubbing me? D:

  • Bleikr Sound
    Bleikr Sound Hace 27 días

    Must note that dinosaur necks and tails are measured in their overall size. When we only measure their main body, they weren't so impressive, yet still larger than any land mammal.

    • trvth1s
      trvth1s Hace 26 días

      just for sauropods. Ornithischians were about as big as mammals and theropoda were smaller then mammals.

  • Rene
    Rene Hace 28 días

    You are two meters? O cant even conseve that

  • SuicideBunny6
    SuicideBunny6 Hace 28 días +1

    I once heard it also had to do with oxygen levels that were x times higher back then than they are today, which also helped them grow so big?

    • trvth1s
      trvth1s Hace 26 días

      problem is oxygen levels from the triassic to the cretaceous fluctuated between 10%-15%, today oxygen levels are a whopping 21%, so nonavian dinosaurs had less oxygen!

  • fidel carter
    fidel carter Hace 28 días

    Less water before the flood. Less pressure. People and animals were huge

  • Ultimate Warrior
    Ultimate Warrior Hace 29 días

    There wasent enough of it,so nature made them super huge with huge lungs.As time went on,they got smaller as the oxygen level become what it is today.

    • trvth1s
      trvth1s Hace 26 días

      problem is oxygen levels from the triassic to the cretaceous fluctuated between 10%-15%, today oxygen levels are a whopping 21%, so nonavian dinosaurs had less oxygen!

  • E DZ
    E DZ Hace 29 días

    oxygen caused every living thing to be bigger. even insects like spiders 😦😥😱😨

    • trvth1s
      trvth1s Hace 26 días

      problem is oxygen levels from the triassic to the cretaceous fluctuated between 10%-15%, today oxygen levels are a whopping 21%, so nonavian dinosaurs had less oxygen!

  • C Steele
    C Steele Hace 29 días

    All that Co2 back then probably helped with the amount of vegetation as in abundance. So plenty of food.

    U.S. PATRIOT Hace 29 días

    They ate spinach.

  • Mike Bales
    Mike Bales Hace 29 días

    How long did dinosaurs live? Do we even know?

    • trvth1s
      trvth1s Hace 26 días

      probably very long, modern avian dinosaurs live long

  • 5helly755
    5helly755 Hace 29 días

    Thicker ozone is one factor. Scientists recreated the earths atmospheric conditions with modern day fish and they grew way past normal size

  • llSRRll
    llSRRll Hace 29 días

    Didn't really explain how they got so large lol. I was under the assumption that the oxygen levels during that time period where a lot higher than now and that allowed them to grow so big. That was just something I heard as a kid so Im sure its completely wrong but nether the less this video really didn't tell me anything other than bone structure.

    • trvth1s
      trvth1s Hace 26 días

      problem is oxygen levels from the triassic to the cretaceous fluctuated between 10%-15%, today oxygen levels are a whopping 21%, so nonavian dinosaurs had less oxygen!
      Only sauropods got really huge and he mentioned why

  • J2 digital
    J2 digital Hace 29 días +1

    Love me some PBS Eons.

  • JASON P.  Roberts
    JASON P. Roberts Hace 29 días

    They got big for food but also to survive things like T Rex

  • Scott Mantooth
    Scott Mantooth Hace 29 días

    those air sacs must have been really handy in preventing injuries when dinosaurs crashed into each other during those stampedes while running away from erupting volcano's or giant rocks falling out of the sky at mind numbing speeds

  • Scott Mantooth
    Scott Mantooth Hace 29 días

    i postulated a theory decades ago that a yet to be discovered species of dinosaur would be called a fluctuasaurus due to the amazing amount of gaseous emissions resulting from a diet rich in high fiber swamp plants and that a finding a complete skeleton would be exceptionally difficult since the fluctuasaurus would not just simply fall over and expire but would be struck by lightning and explode sending dino bits in all directions leaving only a massive crater where it once stood...

  • SergioMartelli
    SergioMartelli Hace 29 días

    Could it also be that air had a much larger oxygen content back then?

    • trvth1s
      trvth1s Hace 26 días

      problem is oxygen levels from the triassic to the cretaceous fluctuated between 10%-15%, today oxygen levels are a whopping 21%, so nonavian dinosaurs had less oxygen!

    GIGGITY GIGGITY Hace 29 días

    Food. Question Answered.

  • Nev
    Nev Hace un mes

    They upsized every meal.

  • Jedidiah Martin
    Jedidiah Martin Hace un mes

    How did dinosaurs get so huge?
    _Sylvester Stallone:_ "Genetics, peewee!"

  • Gods2ndFavoriteBassPlyr

    Fascinating presentation .. Well done.

  • Jimmy Pettersson
    Jimmy Pettersson Hace un mes

    they were around far longer than we have, maybe were misadapted

  • Treborus .x
    Treborus .x Hace un mes

    As I understand it they died out over a very long period not instantaneously asteroid didn't help but the volcanic activity over millions of years in the ancient area of India was far more devastating to the atmosphere ...Also not only dino's were big as Dragonflies were huge ..was it the higher oxygen levels that made the difference ?

    • trvth1s
      trvth1s Hace 26 días

      Dragonflyes were not huge during the dinosaur era, they were huge during the carboniferous era [way before dinosaurs] when oxygen levels were 30%.
      Problem is oxygen levels from the triassic to the cretaceous fluctuated between 10%-15%, today oxygen levels are a whopping 21%, so nonavian dinosaurs had less oxygen!

      nonavian dinosaurs did die out instantaneously within a few years during the asteroid impact. Some dinosaurs were dying out late cretaceous but their niche was being replaced by other dinosaurs. Pterosaurs were still diverse but avian dinosaurs were taking many of their niches, sauropods were slowly being replaced by ornithischians, etc

  • livevil
    livevil Hace un mes

    How Did Dinosaurs Get So Huge?

    They ate Humans.

    • TheRublixCube
      TheRublixCube Hace 24 días

      You mean the consensus of many scientists is invalid, You know what, I'll just llet you believe what you want to believe, arguing is absolutely pointless

    • livevil
      livevil Hace 24 días

      What has Creationism to do with it?
      Anyway, it was meant kind of in a funny way, no point in discussion, but your point is still invalid.

    • TheRublixCube
      TheRublixCube Hace 24 días

      That sounds like a wonderful reality, except Santa Claus is dead, and so are all non-avian dinosaurs circa 66MYA
      Creationism is not a valid field of science

    • livevil
      livevil Hace 24 días

      Yes, ans Santa Claus is your next best friend, of course, we all know that.

  • TrashStuff
    TrashStuff Hace un mes

    Maybe the gravity was a little diferent?

    • trvth1s
      trvth1s Hace 26 días

      definetly no

  • Shoman Blues
    Shoman Blues Hace un mes

    Not very informative.

  • FusRoDah2
    FusRoDah2 Hace un mes

    I love this guys voice and his ability to communicate information. I've seen him on Sci-Show Space as well.

  • Adam Baxter
    Adam Baxter Hace un mes

    So, it wasn't the carbs?

  • Richard Head
    Richard Head Hace un mes

    I'm always curious about giraffes. Why are their necks so long and other animals have normal size. Are they related to dinosaurs?

    • trvth1s
      trvth1s Hace 26 días

      birds have long necks.
      Many mammals like giraffes and camels have long necks to reach high branches, gives them access to more food, sauropods were the ultimate animals in this niche

  • AfroDroid
    AfroDroid Hace un mes

    They grew duh

  • outbackeddie
    outbackeddie Hace un mes

    Somewhere out there in the distant universe, 65 million light years from Earth, there is an alien race that is just now seeing the dinosaurs with a super telescope of some kind. I hope they videotape everything and send the video back to Earth at so that future Earthlings can see what dinosaurs actually looked like. Hey - it could happen.

  • Sam Rahmati
    Sam Rahmati Hace un mes

    So more air circulation in their bones, make Them larger 🤔

    • trvth1s
      trvth1s Hace 26 días

      lighter stronger bones. Ever wonder why birds have such thin legs? They call it ''chicken legs'' because their legs are very thin yet it can support them, this is due to the same type of bones which are stronger then mammal/reptile bones, if mammal bones were that thin we would collapse and break them.

  • Wrecked Gt
    Wrecked Gt Hace un mes

    How much vegetation existed to feed all these dinosaurs?

  • Louisa Clark
    Louisa Clark Hace un mes

    our ancestors used to be very very very cute...。◕‿‿◕。

  • Adrienne Sutherland
    Adrienne Sutherland Hace un mes