The Dinosaur On Your Dinner Table


Hey smart people, Joe here. This holiday season, I bet many of you are
going to be sitting down with family and friends to celebrate. And I bet a lot of you are going to be eating
some nice delicious… dinosaur! Birds are dinosaurs! But why is that? That’s what we’re going to talk about
today. [OPEN] Today I’m here with my friends Anna Rothschild
who makes Science Magic Show Hooray! at The Washington Post, and… fun fact, she’s
25% mashed potatoes. It’s true! I am. And Dr. Shae Montanari, who is not only a
pumpkin beer aficionado, but is a dinosaur expert extraordinaire. Really happy to be here, Joe So we have all heard that birds are dinosaurs,
but what exactly does that really mean? The way that we can tell that anything is
related to something else is by looking at their anatomy and what kind of characteristics
that they share. These are called synapomorphies, traits shared
by two or more groups of organisms, and derived from a common ancestor. Like how humans and chimps both have opposable
thumbs. So, there’s different kinds of dinosaurs
and we can look at the characteristics of birds to find out exactly what kind of dinosaurs
they are. There’s actually lots of clues preserved
in their bones that show that they are very closely related, and that birds are actually
dinosaurs. And we’re gonna find those today, with this! So, we couldn’t get a turkey, it’s not
quite Thanksgiving yet. But everything we show you we promise you
can do at your holiday table with the people you’re celebrating with, and explain to
them the science of why you’re eating a dinosaur. VO: In the 1860s, scientists unearthed the most
famous feathered dinosaur fossil: Archaeopteryx. Early defenders of evolution like Thomas Henry Huxley began
to suggest that these extinct reptiles were so similar to birds, they must be related. But the idea didn’t really catch on until
the 1970s, when new fossils filled in more empty branches on the dinosaur family tree… VO: About 250 million years ago, a group called
Archosaurs split into Crocodilian reptiles, and Dinosaurs. And a lot of evolution has happened since
that split. Ok, so there’s two groups of dinosaurs,
and that’s the Ornithischian and the Saurischian dinosaurs. And that split happened about 240 million
years ago. And the way we know that birds belong to the
Saurischian group is mainly because of their hands. Wait, hands? A: Birds don’t have hands! S: Birds actually DO have hands, they just
don’t really look like hands anymore. If you’ve ever eaten a chicken wing, or
held on to a chicken wing, you’ve been shaking hands with a chicken! Can we dig into this chicken and check it
out? I think it’s time to check it out. Let’s go find a chicken hand. A: So these are like the original chicken
fingers! —
J: I usually dissect these with my teeth, you’re doing it completely differently
So that little skinny part of the wing, at the end, that you don’t typically eat… This little nubbin? That little nubbin, is the finger of the chicken,
that’s gotten super reduced. I accidentally broke off the very tip of the
bird finger, but here is like, the second digit. The very, very tip of the finger. It’s a tiny bird finger. Joe, I’m going to let you hold that as well! The length of the three bird fingers inside
a wing narrows down which group of dinosaurs birds descended from The second finger is longest in birds and
in Saurischian dinosaurs. That’s a big way we know that birds belong
to the Saurischian group as opposed to the Ornithischian group. So birds are Saurischian dinosaurs, but are
all Saurischian dinosaurs birds? S: No, they are not. That’s a great question. So even within Saurischian dinosaurs, as we’re
walking up this dinosaur family tree, there’s another group that branches off and we can
tell which one birds are a part of, and it’s the Theropod dinosaurs. S: And the one bone that is the biggest clue
of Theropod dinosaurs is something that you’ve probably played a little game with after your
thanksgiving dinner: The wishbone! Right here. Cooool! —
I think it’s time to dissect a wishbone. What does the wishbone do? Does it serve a purpose for flight or for
something else? It helps birds get their wishes! Oh right, of course! Besides helping all their dreams come true,
the furcula is actually support for the flight muscles. A wishbone, or “furcula”, is actually
a bird’s collarbones, but instead of two separate collarbones like we have, theirs
is fused into one. Wishbones have only been found in birds and
Theropod dinosaurs, like Allosaurus, and they draw a clear line from those extinct creatures
to our modern feathered friends. J: Ok let’s get this wishbone out in one
piece. This is nerve wracking. I got it! S: You did it! A: Bravo! —
J: So all birds will have a form of this, and all dinosaurs in this part of the tree
also had something like this? S: We’ve found a furcula in most Theropod
dinosaurs’ fossils that we’ve found around the world. —
J: We’ll save this for later. VO: Fossil wishbones are one of the most important
pieces of evidence we have that birds descended from Theropod dinosaurs. S: So actually one of the similarities between
birds and theropods, and how we know that birds are theropod dinosaurs, is inside their
bones. S: This is another one of those tibiotarsus
bones… J: Drumstick bones! S: Drumstick bones, and I have channeled all
of my rage and broken this one in half, and look inside, and you can see that the walls
of the bone is very thin and basically hollow. So when people say that birds have hollow
bones, that’s what they mean. There’s very little spongy bone on the inside,
and there’s a very thin wall, which makes it easier for them to fly. J: Theropod dinosaurs had these hollow bones
too. So did that help them be more agile, you know,
go in for more Jurassic Park type kills? S: Right, that’s a great question. Because theropods had a lot of the characteristics
that modern birds do, but they didn’t fly. So these characteristics must have been helpful
for them to do other things. And hunting is definitely one of them. J: That’s the cool thing about evolution,
is that something that could have helped theropods that didn’t fly in one way, birds could
have taken advantage of that in a completely different way as light weight for flight,
right? S: Exactly! S: So even within Theropods, as we’re going
down the family tree, there’s more branches, and the way we can tell which one birds fall
in is how many fingers they have. VO: Around 200 million years ago, Theropods
split. One branch kept four or even five fingers,
but a branch called Tetanurae all descended from an ancestor with just three fingers. Our bird? Three fingers! Later, some Tetanurans, like T. rex, even
lost an additional finger, going from three to two! Poor T. rex. J: So our chicken, we’ve got one, two, three
fingers. —
S: Ok, so to get to the next identifying characteristic of this bird, we’re really gonna have to
dig in there. J: I’m just ripping parts off here. It’s so… it’s kinda fun actually. It’s like The Brain Scoop crossed with a
cooking show right now. A: For sure. S: Oh man. A: I mean honestly, this entire scene is so
macabre. S: It’s so bad. J: It’s awesome. The darkest thanksgiving! J: You can do any of this with a turkey, it’s
just going to be a lot messier. Which in my book, makes it more fun. —
A: So we know that birds are Tetanurans, but can we get even more specific? S: We can get even more specific. There’s a few more branches to go, before
we get to what we call “crown birds” or living birds. And birds are a specific kind of theropod
called Maniraptoran theropods. So Maniraptora, one of the characteristics
of this group is that the hips point backwards. Specifically, the rearward-tilted bone is
a part of the pelvis called the pubis. J: So we’ve got our backward facing pelvis
for the maniraptorans. Is there another branch beyond this? S: Yeah, there’s still more branches to
go, -but the one we’re going to end on is Avialae. So Aves is part of Avialae. Aves is modern birds
So a big difference between the kinds of theropod dinosaurs that you’re probably envisioning
In your head, like Velociraptor, and birds, is a tail. So birds actually do not have tails. This little bit at the end represents what’s
left of the dinosaur tail, called a pygostyle. So the pygostyle is the last remnants of a
long fluffy feathered theropod tail, and narrows down the bird/dinosaur family tree even further. So. Birds are
Avian Maniraptoran
Tetanuran So. Birds are
Avian Maniraptoran
Tetanuran Theropod
Dinosaurs. And these anatomical features are just a few
of the similarities that scientists have used to place birds in the dinosaur family tree. There’s even more, from the shape of their
necks, to their weird feet, to yes, even feathers. J: Ok, my holiday dinner is never gonna be
the same. It’s gonna be way awesomer, and a little
grosser. But that’s ok. S: So if you want to do this at home, you
definitely can, and if you want to learn more, there’s links in the description. J: You know we’ve taken a deep dive inside
of a dinosaur to see what makes them what they are, but what were they like on the outside? What did they act like? A: That is an excellent question! And if you want to learn more about what colors
dinosaurs were, or even what sounds they made, head on over to my channel where Joe and I
explore those questions. J: Ok, like every holiday dinner, this one
has to end with the traditional breaking of the wishbone. Grab a side guys. 3-2-1… A: What did you wish for? S: I wished for everyone to stay curious!

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Comments

  1. Do any of you realize how far of a stretch it is to assume theses drastic changes that happened to these living creatures. If this theology should be considered fact, think of all the creatures in between those transitions, unless the next transition was made over night. Looking at the fossil record you can see that a lot of animals got killed at once, not over a long period of time. The Fossil Layer is dependent on the rock layer which is dependent on the fossil layer. To make it simple this is similar, Dog+Cat = time of day , Cat+Dog= time of day(circular referencing). This does not make sense because you are taking to separate things adding theology thrown on theology = the age of a layer/bone, then printed hollow fact. The theory was first thought of by some guy heating up a potato, his question was, is the core still hot, yes? We have no clue how the earth was made(we have never seen a planet formed, actually friction of tectonic plates and volcanoes are usually near each other. Why not theorize that volcanoes are created from friction not a magma layer. Gravity is the fuel to your machine, not this endless pit of lava that our surface sits on. By the way, we have only dug 1-2% to the earths core.

  2. This is one of the most interesting videos I’ve ever watched. Like actually though it was so informative and cool.

  3. According to Wikipedia, Archaeopteryx is in the same clade Avialae as modern living birds, but " had many non-avian theropod dinosaur characteristics. Unlike modern birds, Archaeopteryx had small teeth,[13] as well as a long bony tail, features which Archaeopteryx shared with other dinosaurs of the time.[16]"

    So there ARE "modern" birds that had long bony tails, they're just extinct!

  4. Not really relevant but is it only me or does anyone else think Joe looks more handsome in the new videos than the old ones. Something's different about his face…😞

  5. Hello PBS, On the topic of "Scratching and Itch" in that rather itchy video I previously watched, here's one itch that people tend to love to scratch… Why do human beings and even animals have Orgasm? Please correct me if I'm wrong. It is said that only humans and sharks treats sex as a social bond activity and female pigs can experience up to 30 minutes of orgasm. What is orgasm anyway, and why do we experience it? Would PBS mind to scratch this curiosity itch?

    -omg, I'm just as bad as Joe's puns..

  6. I know the cloning of extinct dinosaur species is impossible, but who else wishes it were possible, just so that we could eat them? Only me? I'm the only person here interested in tasting dino meat? Who needs dino parks when you can have dino food courts!?!?!

  7. how did they go through this whole segment without eating any of the chicken

    if that was me i would have eaten the whole thing

  8. It would have been cool if this video also explained the same thing but with the Ornithoscelidan hypothesis isntead of the Saurischian one…

  9. This is a great video for the most part, but you made one key mistake. Archosaurs did not branch into Pseudosuchians and dinosaurs, as you said and showed on your cladogram. They split into Pseudosuchians and Ornithodirans, which themselves split into dinosaurs and pterosaurs. This means that your cladogram is missing a node, where dinosaurs split from pterosaurs. I'm no paleontologist, but I do know a little bit about natural history and dinosaurs.

  10. Thanks for this. I keep hearing that birds are dinosaurs but I could never tell if that was just a buzzword to make birds seem more cool. But what’s the difference between being descended from dinosaurs and being dinosaurs?

  11. Birds are dinosaurs about as much as humans are the tiny shrew like creatures that were the first mammals. Both are the respective result of 160 million years of evolution.

  12. Thanks a bunch for this particular episode. A good (well educated friend) asked me just a couple days ago about how birds came to be classified as a branch of dinosaur. I admit I had to fumble around a bit trying to remember the details of the answer. This episode is the most complete and comprehensible explanation.

  13. The reign of the dinosaurs is not over yet, dinosaurs are still all around us today. The dinosaurs of today aren't giants with scales and reptilian features though, they are now small almost harmless creatures with feathers and beaks. And the dinosaurs now are not the top organisms of the Earth, they're now the second top organisms, behind mammals. But either way dinosaurs are still well alive.

  14. Sorry, but for Ornithoshelida? Is there a new kind of video in which was explained the new classsification of Dinosauria?

  15. Evaluation is fake I believe in nature selection and that people can get smaller and taller in places to there benefits and as you know like loosing finger and stuff like that but I don’t believe that something can come from a single cell let alone an alligator turn into a monster

  16. Can you make Spanish subtitles. Please?

    We watch your videos in our class. Someone in our class doesn't know any English. My friend and I sit with her.(we know Spanish) It became hard to explain to her what was going on, because of some words I didn't know.

    I feel bad for her because just has to listen to a language she doesn't understand. We are getting close to testing season which is very bad for her, because she doesn't understand anything.

    Thanks

    Gabriela Ortega

  17. Just think if we could genetically reverse engineer a chick to be 20 feet tall and lay 200 lb eggs… we could eliminate world hunger…

  18. I think even though we can definitely say that birds are related to dinosaurs, the thing that really makes them dinosaurs is that we keep calling them that…
    By the same logic, we should also be saying that humans are actually fish

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