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Hank talks birds, flight, and dinosaurs with evolutionary biologist Brandon Jackson. Then Jessi from Animal Wonders shows up with a special guest, a white-cheeked turaco named Curly Bird!

Want more animals? Check out Animal Wonders Inc. at http://www.animalwonders.org or on YouTube at https://www.youtube.com/user/anmlwndrs
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(Intro Music) 

Hello and welcome to the SciShow Talk Show where we talk about science here on SciShow

Today we're talking to an evolutionary biologist from the University of Montana. This is Brandon Jackson. 

You're actually our consultant on Crash Course Biology, so thank you for doing that. And now we have you on SciShow to talk about... 

Brandon: the evolution of birds... and bird flight. 

Hank: That is a fasc-- so, like, I have been to your lab 

Brandon: Yes

Hank: And at your lab, you put a little bird into a box and then you blew air at it very quickly 

Brandon: Oh in the wind tunnel? 

Hank: Yeah!

Brandon: Yeah, that's what we call it.

Hank: And it flew! And it was just like hovering there. It was great. 

Brandon: So, we do some of that and then we also do a lot of work on baby birds. And it turns out that that just makes a really good model for maybe what dinosaurs were doing.

Hank: Right.

Brandon: In their kind of - that evolutionary pathway leading up to birds. 

Hank: So, if you're looking at a baby bird thinking maybe the way that a baby bird looks and acts is similar to how early birds looked and acted? 

Brandon: Exactly. All we have from early birds is bones and maybe some feathers. Occasionally in good fossils we'd get some feathers... not all the feathers, but some.

And we try to figure out what those things could have done back then. We'll never know for sure 'cause that was 150 million years ago. But we can guess, and we can look at modern, what we call analogs... modern analogs for these forms and say well, we know this living bird has this form and here's what it does, and so since this dinosaur had that same form this is probably what it did. 

And that's maybe how, whatever it did with that form, that's maybe how natural selection acted on it to turn it from a miniature velociraptor looking thing up into a crow or robin or whatever other bird you're interested in. 

Hank: So, um.. Jurassic Park. I've heard that when that book was written and movies were made, we were fairly certain at that point that all those dinosaurs were feathered. And we just decided not to include that because they were less scary if they had feathers on. 

Brandon: We were-- we were not certain at that point that they were feathered. We are certain now.

Hank: We are certain now? 

Brandon: We are certain now that Tyrannosaurus Rex, at least as a baby, was downy and fluffy. 

Hank: (laughter) 

Brandon: And, yes... and the same with velociraptor, the big scary thing which is a little bit bigger in the movie than it actually was in real life. They have found an ulna, so the arm bone, of velociraptor with quill knobs on it.

And quill knobs are those little bumps you see on like a turkey wing. That's where those big flight feathers come in and attach, and there's muscles and ligaments that attach the bone to the feather to get a nice rigid strong connection so the feathers don't bend. 

And velociraptor had those. And whether or not velociraptor could fly... well certainly if it's a meter or two tall it couldn't fly, but maybe as a kid it could fly. And that's another thing we've actually suggested is that... 

I did some work on Brush Turkeys in Australia and what we have -- my coauthor and I -- argued was that as they get bigger, they actually more terrestrial, more two-dimensional, but the day that they hatch they can fly. 

Hank: Hah. 

Brandon: They can, um, run up vertical or even incline slopes using their wings and then as they get bigger and heavier they get - they live in a flatter world. 

Hank: Right. 

Brandon: And so we actually argued that maybe that's what dinosaurs did. Maybe it was the baby dinosaurs that started out very tiny, and very quick, and very fast, and...

Hank: At sort of a larval state

Brandon: They had kind of this larval state where they were actually more three-dimensional.

Hank: Yeah.

Brandon: More aerial, and then as they got bigger and didn't need to escape from predators by flying or running or making big leaps. As they became an adult velociraptor they didn't have to fly, and they actually became too big to fly.

So, we think baby birds tell us a little bit about how these bones, and feathers could have worked in whatever life stage of dinosaurs you want to talk about. 

Hank: So, um, did you come prepared with something to try and stump me with? 

Brandon: I did. Actually, a piece of recently published science. 

Hank: Okay

Brandon: And so the question is... thinking of cheetahs...

Hank: That has nothing to do with birds.

Brandon: No, nothing to do with birds, but we study locomotion. We study animal movements. 

Hank: Yeah

Brandon: So thinking of cheetahs, what characteristic of a cheetah do you think is most important for it to catch its prey? 

Hank: Uhhhhhhh... This is definitely a trick question. 

Brandon: It probably is. 

Hank: Because you would think, like, speed... acceleration... um, moving fast to catch up to the thing that is running away from it. 

Brandon: Right, right, so...

Hank: I'm wrong! Because...

Brandon: You... kind of.... yeah. 

Hank: (laughter) Okay.

Brandon: So, you said speed, right? 

Hank: Yeah

Brandon: And we all think cheetahs are the fastest animal.

Hank: Okay, can I say acceleration?

Brandon: Oh! Now you - Now you're on to something. 

Hank: Okay. 

Brandon: So, they can run 60 miles an hour, right? 

Hank: It's very fast

Brandon: If you were to try to run your top speed chasing something that's ducking and diving and turning over big mounds of grass and around trees and all that, you actually would have to slow down substantially which is what cheetahs do. Most of their chasing happens around 30, 35 miles an hour, kind of cruising speed for them, but their ability to accelerate, decelerate and change directions is enormous. 

Hank: Yeah, they're so, like, lithe and like bendy and... 

Brandon: And it used to be thought, they have this big bendy back as you kind of described and they have these huge ligaments that run down the back and these big abdominal muscles and chest muscles. And it was always thought that their chest muscles kind of bend them ventrally and that stretches the ligaments in the back and then they dig in their back feet and those ligaments act as springs and they pop out and they straighten the body and they with their back feet dug in, they can shoot off and and take off. 

And so it was this spring loaded acceleration mechanism. And it turns out that that's definitely part of it. But, their ability to be that flexible and to place their feet exactly where they need to turn and to stop and to start. That flexibility is really important for that foot placement as well. 'Cause if you -

Hank: It's not just chasing down the prey,  it's - it's matching every movement that they might make. 

Brandon: Exactly. Or even over-matching to be able to cut them off. You see them turn left, you have to turn left even harder and then accelerate to cut that corner to get them. 

Hank: Hopefully we'll never try and have to run away from one because that would not work out well for us. 

Brandon: No, no. I can't run even 30 miles an hour.

Hank: No, no. I can't imagine I would get much past 10 or 15. 

Brandon: (laughter)

Hank: So, you also came, I think, with some news from your world. 

Brandon: Okay, so from the bird world there was a newly discovered fossil. 

Hank: Yes. Okay. 

Brandon: And I'm not a paleontologist, so I might mess up the name....

Hank: Okay. 

Brandon: Aurornis xui.... or xui... I know that the second part was named after the scientist who described it, a Chinese scientist, and like a lot of these bird fossils that are found in China, they have this amazing preservation because of the way that the fossilization has occurred, the sedimentation is very fine and it preserves fine features. So these Chinese fossils are amazing but it was found by a farmer. No one really knows exactly where it was. 

Hank: (laughter)

Brandon: It eventually ended up at a museum, and then it sat in a museum collection for 10 to 15 years. 

Hank: I hear this story more and more. 

Brandon: Yeah, and some scientists I believe from the Netherlands, just working through the museum found it and described it and is now claiming that it is slightly older than Archaeopteryx, which is the the archetypal bird fossil, the first bird that we know of. 

And every few months we find a fossil, someone finds a fossil, and they describe it and... Archaeopteryx is a bird! Archaeopteryx is not a bird! And then it is a bird. And then it could fly. And then it couldn't fly. Then birds have four wings, and then they had two wings. 

Hank: Yeah (laughter) 

Brandon: And every month or so this changes. And with this new bird, or this new fossil at least, it puts Archaeopteryx back into the bird lineage. It is apparently a few to 10 million years before Archaeopteryx.

Hank: Wow.

Brandon: Its features are more primitive, more basal than Archaeopteryx.  Shorter feathers, different skeletal structures. And it, it's not the missing link between, say, the velociraptors and the Archaeopteryx, but it it helps kind of tell a little bit more of that story. 

But yeah, these fossils that get found in China, found by farmers or found by fossil hunters -

Hank: Fossil hunters, yeah.

Brandon: Who often put 'em on the black market and a lot of times scientists have to buy fossils off the black market or confiscate them,  and so we don't necessarily even know the history of the fossils. We don't know exactly where they were found, or what strata they were found in, how old they might be, are they actually different pieces of different fossils that were all pulled together? 

Hank: Yeah, it's like "We found these... we found a head and a body, and we're guessing." 

Brandon: "Let's stick them togther." 
(laughter) 
That has happened.

Hank: Well that's fascinating, um, yeah. I - I mean you are doing such cool, interesting research. I just love that this sort of stuff happens in Missoula, Montana, though I hear you're leaving? 

Brandon: I am leaving, yes. 

Hank: Ahh. Well, I'm glad we got to have you on the show beforehand. 

Brandon: Yeah. Thank you. 

Hank: So do you wanna look at a - at a real bird now? 


Brandon: Let's look at a real bird! That sounds great.

Hank: Let's look at a bird. 

 Special Guest


Hank: Jessi from Animal Wonders has brought us a real, live bird from the now. And we were just talking while the cameras weren't rolling about how it's so hard to know now what dinosaurs really looked like because you can look so many different ways if you have feathers. For example you have a giant head hair—whoop, it's gone. It's gone and -

Brandon: It's coming back

Hank: It's coming back. So yeah

Jessi: Disappearing act.

Hank: We really have no idea, uhh, it'll just be impossible to really know what they look like until the time machine comes.

Brandon: Yeah time machines.

Jessi: Alright so this—

Hank: Who is - who is this?

Jessi: This is Curly Bird. He is a white cheeked turaco.

Hank: Turaco

Jesse: Yeah, and these guys are really neat. So you're talking about his little hairdo going on up there. That's a crest, and it's made out of specialized little feathers. They're really, you know, fine, and it's only there for display. So when he puts them up like that he gets really excited.

Hank: That's your excitement face

Jessi: Or I move him around. Um, if you wanna put out your hand nice and flat…

Hank: I have my hand nice and flat. Ah get it. Ooh grape.

Jessi: Nice work. Alright, so - 

Hank: Whoa, look at his feathers, wow.

Jessi: Yeah, we'll talk about those in a second. Hide those up, those are a surprise. Alright, so he puts that crest up when he's really excited, or when he's being territorial or when he's trying to impress a lady. 

Hank: Mhmm. 

Jessi: So he might be trying to impress you right now, Hank.

Hank: I'm impressed. 

Brandon: As you should be. 

Jessi: And then when he gets calm, he puts them down. So that's a display. Same with the orange around his eyes there, and he  - There's about 17 different kinds of turacos out there, and some of them use their different colors to do displays as well, different feather colors. We're talking a lot about pigment in feathers, and the turaco is a very interesting bird because of the pigment in their feathers.

So, most birds - it's a refracted light. It's a - it's like a yellow color in there, and then there's some blue that makes it green. So a lot of birds have green coloration in there, and it's not actual pigment - like inside their feather. These guys have their own special pigment inside. It's called Turacin and turacoverdin.  And the turacoverdin is what makes the verde - you know, the green coloration here. And the Turacin is what makes these - and actually this side's better 'case he's been taking baths. But you can see the red - 

Hank: Mmm, wow. 

Jessi: in there. And it ha - it's very high in copper. When they were first studying it, they thought it was high in iron, but it's not. It's very high in copper, and it has these brilliant colors. Now the interesting thing, because it's not refracted light, it's actual pigment, it's actually water soluble. Now, the turacin this color pigment is more water soluble than the turacoverdin of the green here.

So, if I put one of these feathers - if he drops one of these feathers, molts is, and I put it in a glass of water, it leeches it out. And you can see he's been taking some baths recently, it leeches the pigment out, and it turns the water pink, and it turns the feathers this dull white/pinky color like that.

Hank: Weird.

Jessi: So, the turacos aren't the only birds that have turacin and turacoverdin in - turacoverdin actually in there. There are a few others, so they're trying to place them in what family they're supposed to belong in.

Brandon: Mhmm.

Jessi: And they think they're really closely to gallifor - closely related to galliformes, but the turaco is it's own family right now. And they're diverted off a little bit. The red feathers underneath here are very highly prized for African tribes. The chiefs wear them, and it's - like the Zulu tribe over there. It's very common there. 

Hank: Mhmm.

Jessi: So I forgot to tell you where they're from! Africa.

Hank: Mkay.

Jessi: Of course. The eastern part of Africa, so around Ethiopia over there.  So really neat. These guys are also related to plantain-eaters and go-away-birds. So - 

Hank: Plantain-eaters?

Jessi: Plantain eaters. You know what a plantain is?

Hank: Yeah. Like a banana. 

Jessi: It's a banana. Yeah, so these turaco means banana-eater. But it's interesting because these guys don't eat bananas. They don't eat them in the wild. They eat other mostly fruit. And they'll also eat some other vegetation. But they're called - and I'll go ahead and give you another grape. He loves grapes. 

Hank: I love grapes too. 

Jessi: And you can see how he eats. It's got a little chunk of stuff on it too. See how he eats? He doesn't chew it up like a parrot would. He doesn't eat like a Psittacidae. He's gonna take just big bites of it. And these guys are called soft bill birds, becau- not because they have a soft bill. It's - it's hard. But they eat soft foods. So they just take a big bite of it, and then gobble it and swallow it down whole. 

You were talking about flight.

Brandon: Mhmm. 

Jessi: Now I'm kinda monopolizing the conversation. Sorry, guys. 

Brandon: It's alright.  It's a real bird.

Hank: He's - he's just stuck.

Brandon: I'm just, yeah.

Jessi: You were talking about flight. And these - it's interesting 'cause these guys actually, they're not that great of flyers. 

Brandon: Mhmm. 

Jessi: They have short - shorter wings than most birds would and they prefer to run. Now, Curly Bird can't run very well. He was born with a gimpy leg, one of the we have him is because he can't live in a big aviary with other birds. His foot curls up like that. But, a normal turaco has this really cool feet. So most, a lot of birds have 3 toes in the front and one in the back. So they can take their fourth digit here, and it swings.

Brandon: Rotate it.

Jessi: Yeah. It swings back and forth. 

Hank: Goes either way.

Brandon: Mhmm.

Jessi: Yeah. So it can have 2 toes in the front, 2 toes in the back. And a lot of times, his feet - he's not a good example of turaco feet, 'cause he is disabled. But, a lot of times, it'll just hold that extra toe at a right angle. And so they can use those to get to the very ends of the branches, and find foods that they might not be able to get. 

Brandon: Can we try something really quick?

Jessi: Let's see. 

Brandon: Can yo - just, holding him, can you tilt him backwards and let him flap? Will he - 

Jessi: He won't flap.

Brandon: Even if?  Oh.

Hank: Brandon cannot believe it.

Brandon: So, most birds - 

Jessi: Here, I can try to get him to flap if I, if I hold him like this a little bit and see

Brandon: If you hold him

Jessi: We'll see. 

Brandon: Because a lot of birds, when you tilt them backwards, they will try to flap to maintain their feet on whatever they're holding onto.

Hank: Push their feet. 

Jessi: Yes. Yes. 

Brandon: That's what baby birds actually do bef - well before they can fly. 

Jessi: Yeah. 

Brandon: And you don't need much of a wing to do that. And that's what we - one of the behaviors we've argued that dinosaurs could have used to - they could actually run up a vertical substrate. Like up a tree, or up a rock face.

Jessi: Yeah. 

Brandon: by flapping their wings. And so most birds -

Jessi: I'm sure almost every other bird would. 

Brandon: If you do that will, will do that. 

Jessi: Curly's a little bit different. 

Brandon: He's a little gimpy. Yeah, he's a little -

Jessi: He's not used to perching at all. 

Brandon: Yeah.

Hank: Aww. 

Jessi: Yeah, but actually, also, Turacos, when they're babies, they have a little wing claw here. 

Brandon: Yup, so they can kinda hook in just a little bit.

Jessi: So they're - yeah, climbing. They'll lose that when they get their full plummage. 

Brandon: Well a lot of galliformes have that. 

Jessi: Yeah, yeah. 

Brandon: And so they are - that's one of the reasons they think they're closely related to galliformes, is that they maintain a little claw. 

Hank: And I'm gonna eat you.

Jessi: That's - that's not a grape. 

Hank: You were very nice about it though. Just making sure it's not a grape. It looks like a grape.

Jessi: Would you like another grape? My fingers look like grapes now?
Oh! So let's talk about the red under their wings as well. So they would use this red under the wings, if a predator were to be prowling around the forest where they live. They live in a dark forest - dark, dense forest. That's one of the reasons they have shorter wings is when they do fly, they don't want to hit their wings on the - on the close, dense trees. 

When they do fly, if they get scared by a predator, they'll jump up and fly away. And they make this little barking call. Sounds like almost like a chihuahua or a monkey, mixed together. You wouldn't think it was coming from this animal. And he'll flash his red feathers as he flies through the forest, and that's going to warn his friends and family that something scary is out and around. He'll use that, those red feathers under there. 

Hank: Nice. Beautiful bird. You're kind of a dinosaur.  

Brandon: He is a dinosaur.

Jessi: Oh! Sorry. Little flap. The other reason-

Hank: Brandon wants to be clear, he is a dinosaur.

Brandon: Birds are dinosaurs. Absolutely. Dinosaurs did not go extinct. Just - 

Jessi: I was- 

Brandon: Just the non-avian dinosaurs. 

Hank: They just became much smaller... and cute.

Brandon. Yes. Prettier. Yeah. 

Jessi: You're a pretty dinosaur.

Brandon: Yup.

Jessi: I'm really excited to be able - oh, well there's some flapping!

Brandon: There you go.

Hank: Well, there's some flapping for you.

Brandon: There you go. Yeah.

Jessi: He wanted to show you. I wanted to bring Curly Bird here, and I'm really actually happy that I was able to because Curly is 16 years old. 

Hank: Oh, wow. 

Jessi: Which is quite old for a turaco. Usually their life span is between 11 and 12 years old. So he's like a great-grandpa bird. 

Hank: Yeah. 

Jessi: Pretty tough little guy. 

Hank: Great-grandpa, except he probably didn't have any babies. 

Jessi: No babies.

Hank: No babies.

Jessi: He's like a grouchy bachelor. There you go, bud.

Hank: Thank you for joining us grouchy bachelor. Thanks for bringing him in Jessi. And Brandon, fascinating to talk to you about your work.

Brandon: Thank you for having me. 

Hank: Very cool.  And thank you guys for watching. If you want to keep getting smarter with us here at SciShow, you can go to youtube.com/scishow and subscribe.