What's the SMALLEST Tyrannosaurid?

foreign well hi there This Is tyrannosaurus rex possibly the coolest largest and most powerful land predator to ever walk the earth and probably the most famous and well studied of all dinosaurs a dinosaur so awesome that it seems cliche to say that it's your favorite but it is my favorite at least I think it is the Tyrant Lizard King but did you know that it isn't the only Tyrannosaur it isn't the only Tyrant lizard in fact there is an entire family of tyrant lizards the tyrannosauridae with about 13 distinct Genera and today I want to introduce you to all 13 of the Tyrannosaurus find out which one is actually the coolest in which of the 13 is the smallest Tyrant lizard to have ever walked the Earth happy dinosaur December the family tyrannosauridae is a clade of silerasaurian theropod dinosaurs if you know anything about Tyrannosaurus Rex you probably know that it was a big bipedal carnivore with a big head and little arms just not sure how well this plan was thought through master and you probably know that they only had two fingers on each of those little arms and this was true of all of the Tyrannosaurs though some did possess small vestigial third fingers you may have even noticed that they like all tyrannosaurids have an s-shaped neck but there are probably a lot of things about T-Rex and other Tyrannosaurs that you've never noticed before but you won't be able to unsee after today and they're pretty much all related to two things running and bite force the tyrannosaurids were the largest carnivores around almost everywhere they lived but no matter where you would look there were no other dinosaurs that could bite with the same kind of power that Tyrannosaurs could muster their skull was built for strength I mean just look at how much bone is in the skull of Tyrannosaurus Rex now compare that to Giganotosaurus Giganotosaurus was almost exactly the same size as T-Rex but this skull is much narrower and full of big holes the ant-orbital fenestra is huge as is the hole in the lower jaw called the mandibular fenestra that helps keep the skull light but it comes at the expense of strength the Tyrannosaurus skull is built much more for strength as evidenced by its overall width and comparatively small finestra in all other dinosaurs there are paired unfused nasal bones but in the tyrannosaurids those bones are fused into a single arc-shaped bone resulting in greatly increased strength so the skull is strong enough to handle a lot of bite force but what about the muscles on top of the skull is a ridge called A sagittal Crest you see these today in animals like Bears wolves and male gorillas that Ridge gives additional surface area for the attachment of large and Powerful jaw muscles so the skull was strong enough and they had the muscles to bite incredibly hard but could their teeth handle all that Force yes for starters as long as their teeth are the roots are much longer than the part of the tooth that extends out of the skull they're like banana shaped icebergs of death but in addition to those long roots those banana shaped tyrannosaurid teeth look completely different from those of other dinosaurs if you look at the teeth of other theropods like Raptors allosaurids or even Giganotosaurus you will notice that the teeth are blade-like in shape thin and sharp for cutting off pieces of Flesh that isn't what tyrannosaurid teeth look like the bite force of a Tyrannosaur would shatter those teeth ignore for a second the teeth at the front of the mouth the pre-maxillary teeth and look back at all of the big post-maxillary teeth yes they're huge but if you look at them in cross section they're almost circular more like a javelin than a knife much stronger all in all you're looking at a bite force between 35 000 and 57 000 Newtons for comparison the strongest bite force of any living land carnivore the polar bear is a little over 1 600 Newtons and your bite force is about 300 Newtons even Giganotosaurus had a bite force of only around 6 000 Newtons so 35 to 57 000 Newtons of force is astronomical and yet those pre-maxillary teeth are small have you ever noticed how short those premaxillary teeth are on tyrannosaurids they are small and round with a flat back giving them a cross-sectional shape of a capital D these teeth are built to carefully strip flesh off of Bones and are a diagnostic feature of tyrannosaurus so that covers the bite what about the running I mean running can be difficult when you have a huge heavy head but the head is offset to some degree by the huge thick counterweight tail of Tyrannosaurs that places the center of mass right at the pelvis the legs are obviously considerably longer than their arms but they're disproportionately long some of the longest for their size of any theropod but one of the most recognizable features of tyrannosaurids are their feet like most theropods they walk up on their toes with three toes touching the ground and a fourth held off of the ground but if you get a good look at the three bones of the foot the metatarsals you'll notice that they look very different from the metatarsals of other large theropods most large theropods have three metatarsal bones that run parallel to one another all the way to the ankle but in a few groups you see the two outer metatarsals are so large that they pinch off the middle metatarsal creating a structure known as an arctometarsus this arto metatarsalian condition is found in some of the smaller running theropods such as the ornithomimids and the troodontids but also in the later tyrannosaurids it wasn't found in the ancestors of trinid Swords however species like Delong so suggesting that it evolved independently in the Tyrannosaurus from other groups like The ornithomimosaurs this is this convergent evolution similar features that evolved for similar reasons but aren't inherited from shared ancestors the arctometarsus makes the foot very rigid most dinosaurs would lose quite a bit of energy due to flexion of the bones during movement but that is greatly reduced in dinosaurs with this arctometarsus like the later tyrannosaurids so in a nutshell if you want to identify a tyrannosaurid look for fused nasal bones spike-shaped post-maxillary teeth short d-shaped premaxillary teeth and in many cases an arctometarsus which entertainingly enough is what allowed me to notice that the Carnotaurus skeleton at Disney world is actually just a small tyrannosaurid with a Carnotaurus skull on top anyway with all 13 Genera of tyrannosaurids known today and see if we if we determine which of the 13 is the smallest and whether any of them are as cool or even cooler than the king and let's start with the King Tyrannosaurus Rex we know more about Tyrannosaurus Rex than probably any other dinosaur of the Mesozoic Era and of course we do if you're gonna study dinosaurs there would have to be some temptation to study the coolest one it is as we learned earlier this month likely the most massive of all theropods combine that with their unreal bite force and running ability and this was just the super grizzly bear of Cretaceous North America T-Rex like other tyrannosaurids had reduced four limbs with two fingers though not the smallest for its size among the Tyrannosaurus and about 60 teeth in its head keep track of the number as this is one of the best ways to distinguish Tyrannosaurus the number tends to go down as they get bigger Tyrannosaurus Rex was the largest of them all coming in at well over 12 meters 40 feet and almost 9 000 kilos around 20 000 pounds they stood almost 4 meters 13 feet tall at the hips and were the giant land predator of North America until the extinction event at the end of the Cretaceous which we will discuss in some detail later this month so now might be a good time to subscribe and click the little bell if you haven't just yet dinosaur December there is clear evidence that T-Rex was a hunter but also a scavenger it had the largest eyes and likely the best vision of any land animal ever and the wide rear of the skull allowed those eyes to Face Forward allowing T-Rex to have excellent binocular vision combine that with a great sense of smell they were not as fast as many smaller theropods due to their immense bulk but they could see and smell you from hundreds of meters away and there would be little that you could do about it after that it was likely the most formidable land predator the world has ever ever known and while T-Rex was ruling over the island continent of laramidia what is now North America its closest known relative Tarbosaurus was dominating Asia Tarbosaurus is so similar to Tyrannosaurus rex that there has been considerable debate as to whether or not it should simply be considered another species of tyrannosaurus Tarbosaurus meaning alarming lizard and fair enough it was about 10 meters 33 feet long three meters 10 feet at the hip and weighed as much as 4 500 kilos about ten thousand pounds smaller than the king but alarming enough even though it did have proportionally the smallest arms of any Tyrannosaur and sporting 58 to 64 teeth because its skull is not as wide at the rear it likely did not have as good of binocular vision as its North American cousin but it was still the king of Asia until the end of the Cretaceous the next closest relative to the Tyrannosaurus Rex is in another Asian tyrannosaurid zoo king tyrannus honestly to the untrained eye it is very difficult to distinguish Zhu King tyrannus from Tarbosaurus and that is why earlier phylogenies tended to place zoo king tyrannus and Tarbosaurus together in a clade more closely related to one another than to Tyrannosaurus Rex as we've learned more it seems that T-Rex and Tarbosaurus are more closely related but not by much one zuking tyrannus specimen has been estimated to be about 9.6 meters nearly 32 feet long 2.9 meters or nine and a half feet tall at the hips and to weigh around 4 000 kilos or 8 800 pounds other estimates have placed zukang taranas as almost exactly the same size as Tarbosaurus it was first described in 2011 and we may get a better picture of the size to which it could grow as we learn more about them obviously given that these are found in the same basic part of the world as Tarbosaurus we're also from the late Cretaceous and our about the exact same size it is important to be able to distinguish between the two well the distinguishing feature that can be used to differentiate zoo king tyrannus from any other Tyrannosaur is a horizontal shelf present on the max syllabum which is the bone on the side of the skull that makes up most of the upper jaw and if you notice Renaissance use two holes fin stery between the unknows the larger is called the ant orbital finasteride and the smaller more anterior fenestra is called the maxillary fenestra the zoo king tyrannus has a rounded Notch at the front edge of that maxillary fenestra to this point we don't have enough teeth to tell you exactly how many they had though they appear to have had longer serrations than those of any other tyrannosaurid I'd like to take a moment just to point you to this rad skeleton I bought this skeleton for my son Owen a few years back and it is awesome and actually not even all that expensive and we have a link to it down in the description for this video as well as a link to our Amazon store which if you use the links we've got links to all kinds of stuff that you might need as say a reptile keeper or just a dinosaur fanatic and we will have a lot of links to some really cool models and some other cool dinosaur things that you're going to want to see down in our Amazon store and if you buy them the price doesn't change for you but it does help support the channel so if you're looking for a way to support clinch reptiles and content like this and maybe you can't quite afford to support us on patreon or or you just want to get a rad T-Rex why not use our league the next closest relatives after Tarbosaurus and zoo king tyrannus would be the two Genera in the clade Des Pluto sorini those would be despedidasaurus and Thanatos since both are equally related to Tyrannosaurus Rex I will simply start with the namesake of the clade despletosaurus and then make my way over to thanatosis and despiteosaurus the frightful lizard like Tyrannosaurus Rex lived on the island continent of laramidia now known as North America in the late Cretaceous but a bit before T-Rex came around it was also considerably smaller smaller is good right those still frightfully big and at around eight or nine meters long that's 26 to 30 feet 2 000 to 3 000 kilos 4 400 to 6600 pounds and standing just under three meters nine feet tall at the hips it could be distinguished from other Tyrannosaurs by the presence of a very rough surface to the maxilla bone of the upper jaw pronounced crests around the eye and an upright oval shape to the orbit unlike the bizarre Keyhole shaped eye socket of T-Rex it had about 72 teeth more than T-Rex and the longest arms relative to its body size of any Tyrannosaur though that's a bit like being the world's biggest Chihuahua they're still tiny their closest relatives the natotheristis the death Harvester was found in Canada in the lake Cretaceous just before their cousins the despletosaurus though we know of this dinosaur mostly from an incomplete sub-adult specimen it appears to have been similar in size to display thesaurus still still big enough to be deemed the death Harvester and not like Canada's little cutie and it also possessed about the same number of teeth over 70 which is a lot for a Tyrannosaur and I will tell you it would take an extremely trained eye to distinguish between the two that's probably why it wasn't identified as being a distinct species until 10 years after its Discovery all of the Tyrannosaurs that we have discussed so far are more closely related to one another than they are to anything else nanoxaurus the polar bear lizard of the late Cretaceous would be their next closest relative it crazy that polar bear lizard is the cutest name for a Tyrannosaur so far given that the polar bear is the largest land carnivore alive today anyway the polar bear lizard is only known from a partial skull and some teeth found in Alaska thus our knowledge of them is somewhat limited it now appears that they were around 7 meters 22 feet in length but given how limited our fossil evidence is about them it is really difficult to say with much confidence how big they were what is cool is that Alaska in the late Cretaceous was still a place where temperatures regularly got below freezing and food would have been scarce in the winter and it's really fun to hypothesize about how these polar bear Tyrannosaurs survived in such an inhospitable environment the next closest relatives to T-Rex and the other Tyrannosaurs we have discussed so far would be the Dynamo Terror teratophonius and lithronax The Powerful full Terror the monster murderer and the gore King so let's start with Dynamo Terror the powerful Terror this Tyrannosaur from Lake Cretaceous New Mexico was just named in 2018. it is known from a partial sub-adultural adult specimen that was estimated to be around 9 meters 30 feet long so about the same size as dyspletosaurus and its lack of really unique features have led some to argue that it might not be unique from one of its closest relatives teratophonius the monster murderer which is about the same size and existed in about the same time in southern Utah so in about the same exact place as they probably had no respect for future state borders their closest relative Lutheran ax the gore King is another Utah native Tyrannosaur though this one is a bit older and the smallest Tyrannosaur we've encountered so far and this model lithronax was sent To Us by Mike at anti-diluvian animals I first discovered Mike's work on Instagram and it is truly amazing we'll put a link to his Instagram and ours in the description now the gore King is the smallest Tyrannosaur that we've encountered so far somewhere between five and eight meters in length that's 16 to 26 feet and between 500 and 2500 kilos 1100 to 5500 pounds that is a pretty wide range because this is another species known from a single incomplete specimen it can be differentiated from most other tyrannosaurids because the maxilla bone has only 11 tooth sockets where most other Tyrannosaurs have 12 or more well the estimates of its size vary even the high end estimate would make it the smallest Tyrannosaur we have seen so far and with only four more tyrannosaurids left to examine we might just have our winner but all of the remaining Tyrannosaurs are less closely related to T-Rex the largest of them all than is our Utah friend lithronix so let's not Crown the gore King as the smallest Tyrannosaurus just yet all of the Tyrannosaurs that we have looked at to this point are in a single clade within the sub-family tyrannosaurame but the tyrannosaurinae has a second clade called aliora mini a word that literally means different branch which contains two different Genera Ali ramus and Guillen zausaurus both of which are long snouted and found in Asia the long snout in comparatively small teeth of this group suggest that these tyrannosaurids fed on much smaller prey than did the Tyrannosaurs that we've examined to this point aliramis the different branch certainly has a less horrifying name than every member of the last branch of Tyrannosaurs that we looked at and in addition to having smaller teeth in the first Branch it was also probably smaller at five to six meters 16 to 20 feet in weighing 385 to 700 kilos 850 to 1500 pounds only our pal lithronex may have been smaller oh but the other Branch looks to have likely been smaller even than the gorking Ali Aramis was found near the end of the Cretaceous around the same time as Tarbosaurus in Mongolia it can be identified by five crests protruding from the nasal bones and by its 76 to 78 teeth the most of any tyrannosaurid as we know that the number of teeth is generally negatively correlated with size we might have a winner but let's take a look at its closest relative Guillen zausaurus gianzosaurus has by far the lamest Tyrannosaurus name so far it literally just means ganzao lizard gianzao being the place in China where it was found not Soul Shredder not gut Ripper monster man they really missed out on a genuine opportunity unless gianzao China is a really scary place you know what do I know maybe it's the most terrifying place on Earth what I do know is that gianzao Soros was not the smallest tyrannosaurid coming in at a length of 6.3 meters 21 feet 750 to 757 kilos which is like 1 653 to 1 669 pounds and standing two meters 6.6 feet tall at the hips and possibly growing as large as 7.5 to 9 meters 25 to 30 feet it's still at the long thin jaws of its Mongolian cousin Ali Aramis but fewer total teeth and was again somewhat larger so Ali Aramis appears to be the smallest of the tyrannosaurini but we still haven't seen all of the tyrannosaurids because there are two more tyrannosaurids in the sub-family Alberta sorenay Alberta sorne differs in that its members were built more for Speed and less for power being more lightly built with longer flatter skulls than tyrannosaurinae with round eye sockets making them somewhat easy to identify you know Tyrannosaurus has this really weird eye socket they also had shorter Ilia bones as they were overall lighter and had proportionally longer tibia giving them longer legs and a longer stride length than the tyrannosaurini now the two Genera within the Alberta sorne are the Albertosaurus the Alberta lizard like Canada and Gorgosaurus the Dreadful lizard nice to see someone still trying to give scary names to Tyrannosaurus though I have heard that Canadian Winters can be pretty Dreadful too eh you hosers so let's talk about the Tyrant lizard of the great white North Albertosaurus Albertosaurus lived in Alberta Canada and potentially other parts of Western North America in the late Cretaceous about the same time as our current king of smallness Ali Aramis was living in Mongolia but Albertosaurus was certainly larger eight to nine meters 26 to 30 feet and weighing 1700 to 2 500 kilos three thousand eight hundred to five thousand six hundred pounds that's up there with Dynamo Terror and daspletosaurus in length but probably a little lighter as those were both tyrannosaurins and were likely a bit heavier for their length compared to Albertosaurus Albertosaurus was probably a bit taller due to its longer tibia standing 3.4 meters 11 feet at the hip and unlike many of the species we've discussed so far Albertosaurus is known not from only a few fragmentary fossils but rather dozens of largely complete individuals this includes 26 individuals of varying ages that were found all in the same place which has greatly increased our knowledge of this awesome but not small Canadian Tyrant this is one of the few theropods in fact only two of which we have preserved skin Impressions the other being Carnotaurus one of my favorite dinosaurs of all and one I would love to cover in the future you know if you're into that kind of thing these skin Impressions show scales but no indication of feathers like you find in other theropod lineages like the Manny raptora that we covered previously Albertosaurus possessed about 58 teeth which is fewer than its closest relative Gorgosaurus and since we know that tooth number is negatively correlated with size this means that Gorgosaurus may have been smaller than Albertosaurus but was it well Gorgosaurus the Dreadful lizard had about 60 two teeth fewer than Albertosaurus but nowhere near the 76 to 78 teeth of Ali Aramis so things are looking good for our current leader it was found in North America in the late Cretaceous a few million years before Albertosaurus like Albertosaurus it had a long flat skull and Long Legs compared to other tyrannosaurids in fact the two are so similar that some have suggested that Gorgosaurus is just a species of Alberta Source or a direct ancestor which seems very plausible but the question remains was it smaller than Ali Aramis and the answer is nope Gorgosaurus was roughly the exact same size as Albertosaurus eight to nine meters 26 to 30 feet and weighing about the same as well and that makes Alia ramus at 16 to 20 feet our Undisputed champion or does it because I have heard about at least a couple of dinosaurs namely Nano tyrannus and Delong among others that are said to be much smaller still well as of right now Nano tyrannus appears to be a juvenile Tyrannosaurus probably Tyrannosaurus Rex so while it is smaller than an adult Ali Aramis as an adult it was probably the largest theropod of them all at least by mass many of the other small tyrannosaurids like raptorex also now appear to be juveniles of other larger Tyrannosaurus as well but what about Delong Delong the emperor Dragon was truly small not could it still eat a polar bear in a sitting small like Ali Aramis like I might want one for a pet small two meters maybe smaller still but it wasn't a tyrannosaurid there is a debate as to whether or not it is even part of the larger clay that includes the Tyrannosaurus called the tyrannosauroidia and some of the tyrannosaurids were smaller than Ali Aramis but as of today Ali Aramis is the smallest known tyrannosaurid but don't let that fact and its lame name fool you if you were spotted by one you wouldn't stand a chance but is it the coolest as always like And subscribe and we hope to see you real soon I saw a picture of a mantar which is half man half another man hahaha unless it just looks like a man [Music] it's like a different sized and that's exactly what it is because basically you just you have an entire horse with a torso growing out of its neck and so why not bottom man is like going all out right the top man is just chilling yeah enjoying the ride okay [Laughter] just not sure how well this plan was thought through master [Music] what's going on why aren't you seizing the boy [Music] foreign

Channel: Clint's Reptiles

Views: 458,204

Keywords: Clint's Repitles, Dinosaurs, Dinosaur, Tyrannosaurus, T-Rex, Tyrannosauridae, Gorgosaurus, Theorpod, Albertosaurus, Tarbosaurus, Biggest dinosaurs, Smallest dinosaurs, Dinosaur December, Phylogeny, Velociraptor, Jurassic Park, Jurassic World, Giganotosaurus, Spinosaurus, Reptiles, Snake Discovery, Reptile, Kamp Kenan, Clint Explains, accurate dinosaurs, Zoologist, Paleontologist, Evolution, Your dinosaurs are wrong, 65, Official Trailer, Tyrannosaurus vs Triceratops, Prehistoric Planet, Facts, News

Id: GOSW_reV9mE

Length: 27min 37sec (1657 seconds)

Published: Sat Dec 17 2022