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I Know Dino Podcast Present Notes: Xixiasaurus (Episode 84)

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    Our 84th episode kicks off with an interview that includes Dr. Scott Individuals, who has a PhD in evolution and systematics from the College of Alberta, and nonetheless works there researching dinosaur biomechanics and evolution. He works for Dr. Philip J. Currie, who we interviewed again in episode 4. Dr. Individuals has been on many dinosaur digs and he presently research dinosaur locomotion. However the way in which that we came upon about his work is that he presents all the College of Alberta Large Open On-line Programs (MOOCs) on Coursera.org that got here out this 12 months, and he did a very superb job.

    You may attain Dr. Individuals on Twitter @WScottPersons. And you may see the introduction to his Paleo 101 course on Youtube at https://www.youtube.com/watch?v=8jX4_mWAlUg in addition to an superior quick video of the College of Alberta utilizing a helicopter to carry a dinosaur cranium out of the bottom at https://www.youtube.com/watch?v=gJmHONyeLZ8&characteristic=youtu.be.

    Episode 84 can be about Xixiasaurus, a troodontid with sickle claws and eager senses.

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    On this episode, we talk about:

    • The dinosaur of the day: Xixiasaurus
    • Title means “Henan Xixia lizard
    • To not be confused with Xixianykus, an alvarezsaur from the identical formation (Majiacun Formation in China,‭ ‬Henan Province,‭ ‬Xixia County)
    • Kind species is Xixiasaurus henanensis
    • Species title is in honor of the Henanon Province, the place it was discovered
    • Troodontid that lived within the late Cretaceous in what’s now China
    • Described in 2010
    • Chinese language scientists from the Chinese language Academy of Geological Sciences in Beijing and the Henan Geological Museum in Henan described the fossil
    • “From Lü, J.−C., Xu, L., Liu, Y.−Q., Zhang, X.−L., Jia, S.H., and Ji, Q. 2010. A brand new troodontid theropod from the Late Cretaceous
      of central China, and the radiation of Asian troodontids. Acta Palaeontologica Polonica”
    • Fossils discovered on the Xixia Basin
    • Discovered a principally full cranium, which resembles Bryonosaurus, a troodontid from the late Cretaceous in what’s now Mongolia (each haven’t any serrations on tooth)
    • Fowl like
    • Estimated to be 3.9 ft (1.2m) lengthy
    • Had good listening to and sense of odor
    • Very good, one of many highest encephalization quotients of nonavian dinosaurs
    • Cranium is sort of full, aside from its posterior portion (a part of braincase additionally lacking)
    • Cranium is lengthy and just like Byronosaurus
    • Had 22 maxillary tooth
    • Xixiasaurus had fewer maxillary tooth than Byronosaurus, which had a minimum of 30 (however nonetheless had extra tooth than most different theropods)
    • Troodontids have been in all probability carnivores, based mostly on their tooth. Although in 1998, Holtz et al. advised they might have been herbivores as a result of the scale of the serrations on their tooth have been extra just like different herbivores than carnivores (however not broadly accepted)
    • Lack of serrations on Xixiasaurus and Byronosaurus present their meals sources might have modified (they may not slice meat with their tooth)
    • So perhaps Xixiasaurus was an herbivore or omnivore?
    • Troodontidae is a bunch of bird-like theropods
    • Troodontids have been discovered within the Northern Hemisphere solely (North America, Europe, Asia)
    • Largest one was Troodon, and the smallest was Anchiornis (recognized)
    • They’ve intently spaced tooth within the decrease jaw, sickle-like claws, and have been fairly superior
    • Had lengthy legs
    • Had massive brains and enormous eyes, and good listening to
    • Had asymmetrical ears (one larger on the cranium, like owls), which implies they might have hunted just like owls, utilizing listening to to search out prey
    • Enjoyable reality: It’s seemingly that Enantiornitheans lived in colonial nesting websites and in contrast to many fashionable birds they might have buried their eggs.

    For many who might want studying, see beneath for the total transcript of our interview with Dr. Scott Individuals:

    Garret: Dr. Scott Individuals has a PhD in Evolution and Systematics from the College of Alberta and he nonetheless works there researching dinosaur biomechanics and evolution. He works for Dr. Philip J. Currie, who we interviewed again in episode 4. He has been on many dinosaur digs and he presently research dinosaur locomotion.       

    The best way I came upon about his work is that he presents all the College of Alberta large open on-line programs that got here out this 12 months, a minimum of within the Paleontology division and he did a very superb job, so I wished to speak to him.

    Dr. Scott Individuals: Properly thanks very a lot!

    Garret: So, on Coursera the place you introduced these MOOCS it lists you as a dino maniac for the reason that age of two and a half. So what first received you interested by dinosaurs?

    Dr. Scott Individuals: Okay, so I’m instructed I’ve been taken with dinosaurs since I used to be two and a half. I don’t really do not forget that far again, however the story goes that all of it started in Las Vegas the place my dad was on a enterprise journey—reliable enterprise journey and he wished to deliver me again one thing. And there weren’t lots of child-friendly venues in Vegas on the time, however the place there was a spot referred to as the Desert Museum and he went there whereas he was in Vegas and like all good museums he was pressured to exit via the present store. And there within the present store he discovered a really small paperback ebook entitled The Huge Little Dinosaur. It’s a narrative a couple of child sauropod, a child longneck. And he introduced that ebook residence and I had him learn it to me, and browse it to me once more, repeatedly and apparently I used to be simply hooked from there. It’s an awesome story—it’s received a complete Jurassic forged of characters. There’s form of a smart-alecky pterosaur, there’s a really heroic stegosaur, after which the large villain is purple Allosaurus.

    Garret: Oh cool. That’s attention-grabbing, they choose and Allosaurus reasonably than the everyday T-rex.

    Dr. Scott Individuals: Yeah they stored it Jurassic.

    Garret: Yeah, that’s uncommon, really. That folks understand that dinosaurs didn’t all co-exist in a single huge loopy hodgepodge.

    Dr. Scott Individuals: Proper.

    Garret: So, do you’ve a favourite dinosaur? Is it one of many ones from that ebook?

    Dr. Scott Individuals: No—so I’d wish to say that my favourite dinosaur would be the one which I uncover. However proper now my favourite dinosaur, if I needed to choose only one, is a person we name Hannah.

    Garret: Okay. That title is acquainted—is {that a} Styracosaurus?

    Dr. Scott Individuals: So—Hannah is a specific particular person, it’s a skeleton that I discovered final summer season within the Dinosaur Park Formation, and after we first discovered her, we discovered the nostril first. So the horn was simply poking up out of the sediment—we received the entire cranium, and we first thought it was going to be really a Centrosaurus. So one other sort of horned dinosaur due to the form of a few of the ornaments on the frill simply as you get to the very again of it. So simply as you attain the defend. it appeared very very like a Centrosaurus however then as we continued to work across the cranium we discovered these nice huge spikes—the traditional Styracosaurus horn dew sticking on the market on the again. Then it as a result of very, very clear that it was an odd critter that principally appears like a Styracosaurus, but it surely’s received these few horn ornamentations that appear extra consistent with Centrosaurus.

    So proper now we’re pondering it’s in all probability Styracosaurus, perhaps probably it’s a unique species of Styracosaurus—who is aware of. It’s ceratopsians, you would possibly attempt to break up that up even so far as genus stage. Possibly it seems this can be a critter that helps to bridge an evolutionary hole between Centrosaurus and Styracosaurus. However we actually don’t know but and we’re persevering with to excavate Hannah.

    Garret: Gotcha. Final week we have been speaking to Dr. David Hone.

    Dr. Scott Individuals: Oh yeah.

    Garret: Oh, okay so you understand about his zoology background I suppose?

    Dr. Scott Individuals: Yep.

    Garret: And I requested him “How come there are so few dinosaur genus even predicted?” And he identified while you’re doing paleontology, it’s loads more durable to interrupt down the nuance between species, so it makes me assume perhaps that one that you simply discovered will finally be labeled as one thing we have already got by some folks, and different folks would possibly say “Properly it’s really a bridge specimen, in between them.” I preserve seeing that debate again and again.

    Dr. Scott Individuals: The lumpers and the splitters, yeah.

    Garret: Yeah precisely. I like that, lumpers and splitters. So one other space you probably did some analysis was close to Glenrock, Wyoming.

    Dr. Scott Individuals: That’s proper. Sure, sure Glenrock, Wyoming that’s with the Paleon Museum in Glen Rock which is a very cool place.

    Garret: Cool, there are some T-rex tracks there that you simply checked out and also you, sort of, labored on figuring out its pace. Are you able to discuss a little bit bit about how that labored?

    Dr. Scott Individuals: Certain, positive. So I didn’t discover these tracks. These tracks have been discovered by the Glen Rock Paleon Museum’s head paleontologist, Sean Smith and they’re a brief sequence of tracks. They’re within the land’s formation, so that they’re newest Cretaceous. They’re huge, so that they’re… they in all probability are tyrannosaur. They usually’re a little bit bit too small to be an grownup T-rex so they might be a juvenile Tyrannosaurus rex, or—talking of lumpers and splitters—perhaps they belong to a critter referred to as Nanotyrannus which lots of people assume is only a juvenile Tyrannosaurus rex. However yeah so we’ve received a complete sequence of tracks there.

    And what’s neat about it’s you’ve received a left proper left proper sample of tracks you are able to do a tough calculation of how briskly the animal is shifting. And this isn’t a dinosaur that’s racing—it doesn’t report a working tyrannosaur by any means. But it surely’s cool to present a form of baseline for the way the animal is strolling. And one neat factor that appears to point out is that for his or her dimension, tyrannosaurs are taking, as most meat-eating dinosaurs have been, comparatively longer steps than equivalently sized ornithopods. So the Glen Rock trackway reveals that these tyrannosaurs are a minimum of strolling sooner than the duck billed dinosaurs that they have been searching have been strolling.

    Garret: Yeah, so I believe I learn someplace that we’ve discovered a number of tracks of tyrannosaurs strolling, however prints of working don’t actually fossilize nicely, or perhaps simply aren’t widespread sufficient.

    Dr. Scott Individuals: Yeah they’re simply not quite common. So there are a variety of things that play into that. And actually right here we will discuss not nearly tyrannosaurs however we will speak about dinosaurs basically. We simply don’t have very many convincing working tracks for dinosaurs. There are a pair causes for that. One is strictly a chance argument, proper? Take into consideration the period of time you spend or an animal spends strolling vs. the period of time that they spend working, proper? You’re working for under very quick intervals of time—so simply the percentages are that for those who’re going to search out an animal’s observe, it’s going to be doing what it’s usually doing which is strolling. After which added on high of that, is the truth that so as so that you can get tracks preserved, you want to be strolling on sediments floor that’s conducive to preserving footprints. So often meaning strolling of very tender, squishy sediments.

    Garret: Yeah.

    Dr. Scott Individuals: And while you’re shifting on tender squishy stuff, you understand, usually you’re not, you’re not making an attempt to run, proper? Chances are you’ll even be strolling slower than you usually would since you’re being cautious to not slip or to get caught.

    Garret: Is smart. So are you aware if there have been any working fossilized footprints?

    Dr. Scott Individuals: There had been some controversial ones. So the prime instance of which can be some tracks which were discovered down in Australia which can be imagined to protect probably some dinosaurs working—probably even a chase between a carnivorous dinosaur and its prey. However there was so current controversy about that.

    Garret: Controversy all the time appears to pop up with new and thrilling, so…

    Dr. Scott Individuals: Completely.

    Garret: So that you additionally describe Carnotaurus as having an exceptionally lengthy, or massive—I suppose perhaps lengthy caudofemoralis muscle which can have helped it dash however it might not have been in a position to flip very nicely. So what do you assume it may need hunted? Or—how do you assume it may need hunted?

    Dr. Scott Individuals: Yeah, so Carnotaurus is a very bizarre, actually cool critter and it’s received the one most weird dinosaur tail I believe I’ve ever seen. That’s together with issues like Ankylosaurus and stegosaurs. So Carnotaurus’ tail is so weird due to what we will name the transverse processes or caudal ribs. And so the tail after all is an extension of the spine, so it’s composed of a sequence of vertebrae and the caudal ribs are bones that stand out from the vertebra often to the edges. So on any respectable meat-eating dinosaur’s tail you’ve received a pleasant lengthy sequence of those ribs on both aspect. However on Carnotaurus, they get freaky. They level approach the heck upwards, so not a lot out as up. And on the ends of those ribs, they’ve received these bizarre hooks to them so it appears just like the dinosaur’s virtually received a row of query marks working down it’s backbone. And the way in which that these hooks, while you articulate the tail skeleton, they line up one immediately behind the opposite and so they form of overlap and make contact with those in entrance of and behind them.

    So that you’ve received this tight interlocking sequence and we additionally see some proof on the lateral floor of these caudal ribs giving us—we predict—some indication of the place the totally different muscle groups hooked up. And based mostly on my analysis taking a look at dissections of modern-day reptiles, we predict that the muscle that’s most fairly filling that house on the edges of the tail is the muscle referred to as the caudofemoralis which is definitely a muscle that’s tied to the leg. So it’s an enormous muscle within the tail that’s hooked up to the femur—the higher leg bone—by the tendons. When the muscle contracts it pulls the leg backwards or for those who’re planting your foot and your contracting that huge caudofemoralis muscle it’s was pulling your physique ahead, is what’s supplying you with your energy stroke. By angling the caudal ribs upwards in Carnotaurus you’re increasing the scale for this muscle, which suggests Carnotaurus has an elevated locomotive oomph. It’s simply received extra energy in it’s trunk, which like a Volkswagen beetle is the engine and in order that presumably would give it extra energy, let it to run sooner.

    Once we say I don’t assume it will possibly flip notably nicely, it’s simply because by having that tight interlocking sequence of tail vertebrae, it means your tail is much less versatile and also you in all probability have to show the entire thing extra as a unit, which can enhance your rotational inertia, making it more durable so that you can pivot rapidly. Now by way of what Carnotaurus was really searching, that’s a difficult query. We don’t have any good direct proof of that. However one little bit of hypothesis that we put forth in our paper describing Carnotaurus is that, as with all bazaar dinosaur diversifications, this one didn’t simply pop into existence in a single day. We see in a few of Carnotaurus’ different South American kin, we predict is a reasonably gradual development main as much as this weird tail kind. And through that point, a minimum of when these ancestors of Carnotaurus have been round, you understand, a few of them have been coexisting with a few of the nice huge predators of South America. So issues like Mapusaurus and Giganotosaurus—the actually huge guys. And have been pondering nicely perhaps this represents a little bit little bit of area of interest partitioning.

    So that’s Carnotaurus and its ancestors may be changing into extra specialised to run actually quick and in flip each keep away from being eaten by these different huge tremendous predators however perhaps they’re additionally higher at catching a few of the smaller sooner critters. So perhaps going after a few of the ample South American ornithopods and probably could also be leaving the large sauropods there for Giganotosaurus and its crew to deal with. Now that being stated, we don’t have direct proof of Carnotaurus itself coexisting with a few of these different huge predators. However that will very nicely be only a perform of pattern dimension. As a result of we actually don’t know loads in regards to the different animals that share the actual atmosphere, the actual time limit with Carnotaurus.

    Garret: So it makes Carnotaurus look extra like a cheetah and a few of these different guys look extra like lions or one thing.

    Dr. Scott Individuals: Yeah, perhaps that’s comparability.

    Garret: Okay. Cool, yeah. I’m additionally sort of shocked, such as you talked about the ebook that you simply had as a child, that the Carnotaurus doesn’t pop up extra as an enormous villain—as a result of it’s even received the horns and every part.

    Dr. Scott Individuals: It does, it does. Properly Carnotaurus has been the villain in popular culture a little bit bit, proper? In case you assume again to Disney’s Dinosaur, with the iguanodons and the large migration story, Carnotaurus is the large dangerous.

    Garret: You’re proper.

    Dr. Scott Individuals: In that movie, the truth is they make them larger and badder than the animal was. Proper? They blow it as much as the scale of a tyrannosaur. So it has gotten to be villainous in that approach. Carnotaurus makes a cameo within the second Jurassic Park novel, the place it’s a scary critter trying at nighttime and it’s received camouflage powers, I believe.

    Garret: I’ll should re-read that. It’s been a very long time since I’ve learn the Jurassic Park books. Do you assume that it may need been the quickest massive carnivore? Or do you consider one thing extra like a Dakotaraptor or one thing would have been faster?

    Dr. Scott Individuals: OK, so really I might argue to you that though the raptors, the dromaeosaurs a minimum of, get lots of publicity for being quick, thanks largely to Jurassic Park. Truly while you have a look at their limb proportions, most of them, say while you have a look at the size of the decrease leg, the size of the shin, and the size of the metatarsal—so a few of the foot bones which rely successfully as leg bones in these guys due to course they’re standing on their toes so the foot is raised up and contributing to the size of the leg. They’re really not that elongate—they don’t actually have the legs of a sprinter.

    I have a tendency to think about a traditional raptor dinosaurs or the dromaeosaurs as perhaps being extra like wolves and coyotes by way of their athleticism than like cheetahs or different huge cats which can be actually, actually good sprinters. Now if I needed to wager, you understand, I in all probability wouldn’t say that Carnotauruses, even among the many huge theropods was essentially the quickest. We don’t have a whole decrease leg of the Carnotaurus, so it’s a little bit laborious to say that. Possibly it does. Possibly after we discover the total leg it would shock all of us. However you may want—you’d should exit to the Dino Derby and place a wager, you would possibly go for a small to medium sized tyrannosaur really…

    Garret: Okay.

    Dr. Scott Individuals: Of the large predators as a result of it received actually, actually lengthy legs. Tyrannosaurus are tremendous leggy—form of the Radio Metropolis Rockettes of the dinosaur world.

    Garret: Have you ever talked all of it to the group that’s making the sport Saurian in any respect?

    Dr. Scott Individuals: No I haven’t.

    Garret: They describe T-rex in virtually the very same approach. It’s simply—they are saying Sue has legs for days, she will simply run so quick tremendous simply. Cool—so aside from working means, or maybe how rapidly they will change route, what else can we find out about dinosaur locomotion from fossils?

    Dr. Scott Individuals: Okay, in order I stated an enormous a part of my work focuses on taking a look at dinosaur muscle groups and making an attempt to determine from the skeletons the place they’re hooked up. And so far as we talked about taking a look at simply the proportions of the limbs as they relate to hurry and in addition trying on the dimension of the tail muscle. One different factor that I have a look at, which is form of a mixture of these two, is making an attempt to assume a little bit bit in regards to the leverage concerned within the muscle and skeletal system.

    So as an illustration, one cool subject that my advisor Dr. Phil Currie and I attempt to deal with is the thriller of the profitable duck-billed dinosaurs. So if we think about a online game, proper the place we get to journey again to the Hell Creek, the commonest dinosaur, […] I might think about, that they’d have you ever encounter might be going to be, a minimum of of the large ones, goes to be a duck-bill. As a result of duck-bills are like in every single place. In North America a minimum of they simply outnumber all the opposite varieties of huge dinosaurs—they’re actually, actually profitable. Which can be actually, actually bizarre as a result of, I imply, as a online game character goes it will seem to be the duck-bill dinosaurs could be just like the most secure factor you might attempt to assault, proper? That’s like stage one. It’s only a duck-bill. It doesn’t have horns, it doesn’t have armour, and for large animals that’s one thing that’s actually bizarre.

    So there’s this concept in fashionable ecology and excited about the evolution of ecosystems that claims, you understand, as an animal will get bigger, because it will increase in physique dimension, it’s atmosphere turns into progressively extra two-dimensional. Okay, as a result of for those who’re a very, actually huge animal there are fewer objects within the atmosphere which can be, primary, an impediment for you, proper? Every little thing will get progressively flatter—there are only a few issues that you would be able to not cross. They you can’t easy step over for those who’re the scale of an enormous dinosaur. Okay, and that has implications for predator avoidance methods, proper? If you’re a little bit critter, then your world is stuffed with rocks and bushes and grass and issues that you would be able to conceal behind. You’ve received the choice—you possibly can burrow and make your personal hidey gap, you climb up timber and issues like that. In case you have been an enormous dinosaur, these actually weren’t choices for you and so methods based mostly on crypsis and concealment—so hiding out of your predators in all probability doesn’t work as a result of they will see you. There’s no place to cover.

    And so that you want extra direct strategies for coping with your predators and we see that right now for those who have a look at huge megafauna like in Africa, for instance. You see a pair totally different methods. You are able to do what elephants do, you possibly can simply get to be so huge {that a} predator can’t deal with you—actually not one on one. You generally is a warrior, like a cape buffalo or rhinoceros—you possibly can develop a weapon that makes it harmful for a predator to attempt to muck with you. You generally is a fortress, like a crested porcupine, or a large floor pangolin—so that you’re so nicely armoured and pointy that you simply’ve received no susceptible spots. Otherwise you generally is a speedster like a gazelle or antelope. You may match your predator step for step and make it in order that they will’t catch you. If we glance again on dinosaurs, we see lots of parallels, proper? We’ve received large sauropods, they’re giants, we’ve received ceratopsians, which actually appears to take the warrior technique, you’ve received some fortresses within the case of the large Ankylosaurus, clearly you’ve received speedsters with a few of the small ornithopods or the Ornithomimus and naturally the large predators in that state of affairs could be the tyrannosaurs. However duck-billed dinosaurs—they don’t appear to suit into any of these, proper?

    They’re not tremendous huge, most of them a minimum of. They overlap with the scale of their predators. They don’t have very huge horns, they don’t have armour, they’re actually not fortresses. The query is—nicely, okay, are they speedsters? Can they be as quick as their predators? Properly, after we have a look at the size of a duck-billed dinosaur’s leg, seems, no, it’s a lot shorter. The identical sized Edmontosaurus has received a a lot shorter than the identical sized tyrannosaur’s. It doesn’t seem like they may outrun them, however one factor my analysis means that the attachment aspect for the caudalfemoralis is basically, actually excessive up on the femur. It attaches very excessive up on the femur—it attaches very excessive up on the tyrannosaur. That’s nice for prime pace working, proper?

    You’ve got it hooked up excessive up so a really quick contraction of the muscle is sufficient to swing the leg backwards and forwards via one complete energy stroke. So in a short time, contact, contract, contract. Your tyrannosaur can swing its leg very, in a short time—nice for sprinting—cool. In a duck-billed dinosaur although, it’s hooked up actually, actually far down. So that you’ve received a sluggish contraction, or else very quick steps. Once more, that parallels with what we see within the dinosaur footprint report—duck-billed dinosaurs taking shorter steps. That makes you slower. However by positioning it decrease down, proper, you’re extending the second arm. You’re giving your self much more leverage for that muscle, proper? It’s like—think about a door. You set your door deal with distant from the hinge, it makes it good and straightforward to open. In case you put it actually, actually near the hinge, you bought to essentially work in an effort to swing the door open. Identical factor could be true for these dinosaurs and their legs.

    So the thought is nicely, whether or not or not a tyrannosaur can catch a duck-billed dinosaur would possibly actually rely on what sort of a race you’re working. In a brief dash, positive. The tyrannosaur can overtake it straightforward, but when it’s an extended race, if the duck-billed dinosaur sees you coming from a distance, nicely then it will possibly run and run and also you’ll achieve on it for the primary couple of minutes, however then your caudofemoralis goes to be aching and burning and the duck-billed dinosaur, with it’s superior leverage you understand, it’s sluggish however regular would win that race.

    And certainly, for those who then apply that again to our African analogue, you see that, nicely, what’s the primary, cheap sized herbivore that you simply usually encounter on the plains of the Serengeti? Properly, it’s issues like zebra, and wildebeest. And the zebra is a quick critter, can transfer 30-35 miles per hour. However the lion can do 50, cheetahs which do assault zebras can do 60 and up. So these huge cats are sooner, however the zebra has received superior endurance such that the cat can solely overtake them in the event that they get into a really slim putting distance.

    Now think about you’re a duck-billed dinosaur. You’re not having to be looking out for a stealthy cat shifting via the tallgrass. As an alternative you’re looking out for a predator that’s actually the scale of a billboard signal and also you’re a herding animal, so that you’ve received a number of eyes and ears and noses—all on the alert. For a predator with the flexibility to provide you with a warning in the event that they’re noticed. So we might argue that an endurance based mostly technique may be very viable for duck-billed dinosaurs. And perhaps that was a minimum of partially key to their success and positively for his or her continued survival alongside tyrannosaurs.

    Garret: Yeah, that makes lots of sense.

    Dr. Scott Individuals: You understand perhaps, perhaps within the online game the duck-billed dinosaurs aren’t even an animal you get to work together with. Possibly they’re simply form of a background critter that runs away as quickly as you get shut and also you by no means made any progress.

    Garret: Yeah, as a result of sneaking up as a T-rex goes to be a little bit tough.

    Dr. Scott Individuals: Yep.

    Garret: So that you have been concerned within the discovery of the “Romeo and Juliet” discover which is believed to be a mating pair of Oviraptors. Are you able to inform us a little bit about what you probably did there?

    Dr. Scott Individuals: So I ought to make clear—first off I used to be undoubtedly not concerned within the discovery of these specimens. I used to be not even on the identical continent—they have been present in Mongolia. What my position has been is that after a bunch of laborious working of us discovered the specimens, cleaned them up, and introduced them for examine on the American Museum of Pure Historical past, I used to be one in every of many researchers that was allowed to return in and take a look at them and examine them. In order background goes, yeah—Romeo and Juliet are a pair of Oviraptors. They have been discovered very, very shut collectively, they’re superbly preserved. It appears like they might have died in the identical occasion. Possibly they received buried as an enormous sand dune got here down over high of them. So it appears like they died virtually in one another’s arms and in order that gave them the nickname Romeo and Juliet. It was one in every of a few nicknames they received. They have been additionally nicknamed Sid and Nancy, and in addition Batman and Robin.

    Romeo and Juliet was the title that actually caught as a result of it conjures up the picture of “Oh, what a tragic loss of life for these dinosaurs, perhaps they have been in love.” Okay, so what I did was, I used to be taken with tails, and though these two critters are mainly similar in each regard, the one which’s named Romeo is barely bigger. However they’re mainly similar besides while you go to take a look at their tails. So the tail vertebrae are very totally different as are the chevrons, and chevrons are the little tailbones that stick down beneath.

    And within the specimen that’s nicknamed Juliet she’s received a reasonably normal sequence of chevrons—Oviraptors didn’t have many versatile tails, they have been really fairly beefy tails too. However she’s mainly a par for the course, wasn’t an enormous shock. However then while you have a look at Romeo, he’s received these chevrons that actually begin to change form very radically as you progress previous the bottom of the tail. And it develops this virtually spearhead like form to it which I took as indication of, “Wow, what a powerful attachment level for some muscle groups that you simply’ve received occurring there.” These caudal ribs are proportionately longer in Romeo as nicely.

    And the explanation that we will take into consideration relating tales to romance in oviraptorosaurs is that a lot of them have gotten what we name pygostyles—so a sequence of fused vertebrae proper there on the tip of the tail which is one thing you additionally see in birds. And we predict that these pygostyles have been there to assist a fan of feathers. So a little bit bit just like the followers of feathers you see in modern-day birds. And we all know from a critter referred to as Caudipteryx really preserved in China one of many specimen’s stunning asphalt specimens the place you really bodily see a fan of tail feathers. So we all know that these critters have gotten this construction.

    And if you consider modern-day birds with huge followers of feathers do with them after they’re not utilizing them to assist them fly—and certainly these oviraptors are flightless—one perform is that you simply use them as a sexual show construction, proper? You flaunt them, you flash them in mating dances. You employ them to draw the alternative gender. And naturally, as is commonly the case, these sexual signalling gadgets are usually sexually dimorphic that means they’re larger, they’re extra exaggerated in a single intercourse than within the different. And naturally as a result of it’s often the males that should do the promoting, it’s to the males that the onus of doing the mating dance, of doing the convincing, that duty falls to. It tends to be the males that have gotten the extra elaborate show construction.

    So after we noticed that these two dinosaurs appeared to point out what may be sexual dimorphism of their tails, we determine probably the one which’s received the butcher tail, the one which appears higher tailored to swing and flaunt and wave its tail about is extra seemingly the male. Because it occurs, that’s the one which did get the nickname of Romeo. So we advised, “Yeah, you understand Romeo and Juliet might the truth is be a male-female pair. Possibly this actually is the tragic dinosaur love story that the press initially made it out to be.”

    Garret: Cool, yeah. That’s generally not the case that the press jumps on a cool title.

    Dr. Scott Individuals: Oh, yeah.

    Garret: Particularly every time tyrannosaurs become involved, however… So one different paper that I discovered actually attention-grabbing is on Sinocalliopteryx.

    Dr. Scott Individuals: Oh, sure.

    Garret: And the paper describes it as seemingly a stealth hunter.

    Dr. Scott Individuals: Mhmm?

    Garret: Are you able to discuss a little bit bit about what clues there have been for that conclusion?

    Dr. Scott Individuals: Certain, positive. Okay so Sinocalliopteryx is a really cool critter for China. It’s associated to a really small […] (00:28:18) dinosaur though it’s really pretty massive for its group, so it’s pushing wolf dimension. And the explanation there was dialogue about it being a stealth hunter is as a result of contained in the preserved ribcage of some Sinocalliopteryx specimens we discover the stays of some early primitive birds. Contained in the specimen of one other one we really discovered the leg of a raptor—a little bit raptor. So like a relative of, like Microraptor. And these are critters that have gotten wings within the case of birds. They’re actually a minimum of critters that have been able to flight. And in order that’s form of an uncommon prey alternative for a land sure predator to be going after. Apparently, with some regularity, proper?

    A number of cases present these sorts of prey preserved. Based mostly on that, we will counsel, nicely perhaps we will evaluate Sinocalliopteryx to some modern-day predators which can be good at catching prey that may fly. In order that’s one thing that, say, foxes can do. Clearly that’s one thing that lots of cats do and so they wa… that do… that’s, they’re actually, actually good at sneaking up stealthily after which pouncing on their prey earlier than they appear them and so they’re in a position to take off. And so Sinocalliopteryx appear to have an irregular choice for flighty prey. We propose that perhaps it was notably good at that.

    Garret: Okay, so simply trying on the abdomen contents alone you possibly can draw the conclusion, you didn’t should look an excessive amount of at… I suppose it helps that it’s small, in all probability.

    Dr. Scott Individuals: It helps that it’s comparatively small, after we take into consideration the limb proportions of Sinocalliopteryx. Truly it’s received a very, actually lengthy decrease leg—it was additionally a reasonably quick critter. So you possibly can undoubtedly think about it discovering its feathery prey after which sprinting in an enormous lunge, or huge pounce to nab it.

    Garret: Okay, very cool. One different dinosaur examine query that I’ve for you is you’ve talked a little bit bit a couple of non avian theropod swimming in China and we noticed the same observe that got here out of the UK lately.

    Dr. Scott Individuals: Mhmm?

    Garret: What do you assume would make a dinosaur wish to swim? Or the place would they be swimming?

    Dr. Scott Individuals: Oh, so I’ll let you know—after I was rising up, on of the large films earlier than Jurassic Park was after all the Land Earlier than Time.

    Garret: Mhmm, that’s in all probability our favourite.

    Dr. Scott Individuals: All proper, cool. Properly you keep in mind the large climax within the Land Earlier than Time is when Littlefoot and his posse make the large stand towards Sharptooth the tyrannosaur. And the way in which they defeat him is they simply form of knock him right into a puddle. They usually say it’s so deep down there that he gained’t be capable to swim with these scrawny little arms. And for a very long time there was this form of concept that, you understand, except a dinosaur had clear diversifications or what we thought have been clear diversifications for having the ability to swim, you understand, they have been land sure critters. They didn’t go into the water and perhaps Tyrannosaurus rex and what not couldn’t even swim. It’s really a reasonably foolish factor to assume, I might argue.

    In case you have a look at modern-day critters—even animals that principally hang around on land, for those who put them in water, they float—they’re completely able to swimming. Some might actively attempt to keep away from the water however there are additionally loads of huge mammals right now which can be completely blissful to go for a swim. And there are a lot of the reason why they may select to try this. Could possibly be so simple as, “Ah, we have to cross this river, this physique of water to get to the opposite aspect.” It might be, “It’s good to take a pleasant refreshing dip.” Possibly it’s good for eliminating parasites, perhaps it’s simply a great way to chill off.

    So I really think about that lots of dinosaurs had many causes, many alternatives to get their toes moist, to go for a pleasant little swim. And despite the fact that Tyrannosaurus rex has received these tiny little arms, it’s received large lungs. It could be very, very buoyant. It could be laborious to sink a Tyrannosaurus. Plus, it’s received big toes and actually highly effective legs. The animal may actually swim, it may do that form of duck paddle, which is a few of what we predict these tracks present—the dinosaur simply touching backside and scratching alongside because it strikes. And naturally, it’s additionally received the nice huge tail that it may actually transfer backward and forward to assist propel it via the water. So I don’t assume you might kill a tyrannosaur by dropping it within the water.

    Garret: So are most of those swimming tracks actually that transitional, the place they go from strolling to clawing a little bit bit at surfaces as a result of they’re beginning to float?

    Dr. Scott Individuals: Yeah, so I imply—and that’s not shocking, proper? As a result of the one place that you might get a swimming observe is when the dinosaur is simply starting to begin to swim, as a result of after that it’s simply padding via the water. And the water gained’t fossilize it to present you a observe. So the place you are inclined to get it’s proper the place you’re shifting into the deep finish.

    Garret: That’s superb to me, particularly it’s so laborious to search out working tracks, however we will discover these swimming tracks periodically.

    Dr. Scott Individuals: Certain, positive. And that once more pertains to the sort of atmosphere, proper? You have to have considerably moist moist sediment so that you can get a observe that will get to be preserved, and naturally you’ve these round watery environments. And watery environments are additionally the place you’re going for a swim. So that actually will increase the chance of it.

    Garret: Cool. Do you’ve any plans for making another paleontology MOOCS? Or perhaps now that you simply’re an official physician, any individual else is taking that over?

    Dr. Scott Individuals: We do even have plans to do some fast revisions, perhaps add in a number of issues, contact on some stuff we both didn’t get an opportunity to do, or didn’t get an opportunity to do justice to. So there are some revisions, some replace additions to the Paleo MOOCS which can be scheduled. At present although, there are not any huge plans that I’m concerned with for the second. However you understand, they’ve simply come out, there’s going to be a time frame of ready to see how they’re acquired.

    Garret: They’re nice. Most likely the most effective MOOCs I’ve taken, so—wonderful work.

    Dr. Scott Individuals: Okay, thanks! That’s nice to listen to.

    Garret: Yeah, I usually advocate it on the course for everyone to take the Dino 101 and the Early Theropod.

    Dr. Scott Individuals: Theropods and the Origins of Birds, yeah.

    Garret: Sure. I additionally took the opposite ones, despite the fact that they’re not about dinosaurs. Simply since you did such job.

    Dr. Scott Individuals: Thanks!

    Garret: So, one remaining query.

    Dr. Scott Individuals: Okay?

    Garret: We’re going to be visiting the Philip J. Currie Museum and the Royal Tyrrell Museum in a few weeks on a street journey.

    Dr. Scott Individuals: Oh, cool. Now you’ve been earlier than, proper. To the Royal Tyrrell, I imply?

    Garret: We haven’t been in any respect, which is…

    Dr. Scott Individuals: Oh, you haven’t! Oh my gosh—nicely you’re in for a deal with.

    Garret: Is there something specifically that we must always find out about or something?

    Dr. Scott Individuals: I let you know what, while you undergo the very first gallery on the Royal Tyrrell Museum, when you come out of the attractive room that’s received these life-sized albertosaurs you’ll enter into what appears like an artwork gallery virtually. The skeletons are behind little portraits within the wall, and also you’ll come to 2 stunning loss of life posed skeletons. Considered one of them is a juvenile Gorgosaurus, the opposite one is a ornithomimid—and so they’re attractive and also you’ll be blown away with the Gorgosaurus’ tooth and its claws. Take note of the again finish. Take a look on the tail and take a look on the chevrons, once more these little bones that stick down on the underside. And see for those who can spot the purpose the place these chevrons start to alter their form.

    In order that they’ll go from trying like elongate finger-like projections as much as extra form of a ship form to them. And proper while you see that transition, you’ll be capable to see a little bit sequence of scars, of little ridges working down the floor of these chevrons. And that, as I’ve argued within the literature earlier than might very nicely characterize the purpose the place that caudal femoralis muscle, that huge muscle that was powering that juvenile Gorgosaurus and that ornithomimid as they have been working and sprinting via the Cretaceous panorama. You may see the purpose the place it begins to taper out and a few of the muscle strikes in to take over it’s place. So search for that.

    Garret: I’ll! Now that you simply’re a health care provider I’m positive you’ve a really vibrant future, and an excited to see the primary dinosaur that you simply get to call.

    Dr. Scott Individuals: Okay, nicely thanks very a lot and thanks for having me on the podcast!

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