The Scientific Accuracy of Walking With Dinosaurs - Episode 6: Death of a Dynasty

Walking with Dinosaurs has had such an impact on people around the world undoubtedly inspiring many people who were young children when they first watched it to pursue a career in paleontology I can count myself at least among those people with this series playing a major part in developing my love for and fascination with our planet's ancient past Walking with Dinosaurs was instrumental for not only being the first TV show filmed like a nature documentary that recreated dinosaurs using CGI but also for portraying the prehistoric animals in a remarkably realistic and natural way showing them not only as bloodthirsty monsters but as complex animals with diverse behaviors the emotional stories of creatures trying to survive in these prehistoric worlds and following a single individual or group of individuals throughout the episodes is a brilliant way to get people invested in the lives of these long- gone animals and something that I feel still goes unmatched in any other dinosaur documentary since I absolutely love this show if you can tell and it's been so much fun reviewing all these episodes to see how far our understanding of paleontology has progressed in the more than 20 years since the series aired from the reception these videos have gotten it's clear a lot of other people have also enjoyed this and so I'm happy to finally give you the scientific accuracies and inaccuracies of the last episode what did Walking with Dinosaurs get right and what did it get wrong with death of a dynasty this episode takes place 65.5 million years ago in Montana at least it does in the UK version of the episode as apparently in the American dub it's said to be set in Idaho I'm not quite sure why this change was made though considering that the hell Creek formation is not known to outcrop in Idaho but anyway the date of 65.5 million years ago for the time of the asteroid impact is actually now outdated with recent studies utilizing potassium and uranium Isotopes to get a more precise date of 66.4 3 million years ago for the age of the Cretaceous p Gene boundary of course the main star of this episode is the Tyrant reptile King itself Tyrannosaurus Rex the temptation to include T-Rex in a dinosaur documentary is just too much sometimes and honestly I can understand there's um a lot to say about this T-Rex design but before we get into that it's worth pointing out that it is indeed living in the correct time with Tyrannosaurus known from both the lower and upper Hell Creek formation so let's get straight to it obviously this is a very questionable T-Rex design and possibly one of the strangest in all dinosaur media the biggest issue is just that the basic proportions of the animal are completely off the body looks far too skinny with a tail and neck that are both way too short and apparently missing a lot of the powerful musculature in these areas the legs are also much too slim and don't even look capable of supporting the rest of the body and the feet are also strangely small compared to the overall animal the skull shape is also just a bit of a mess I'm not really sure what went wrong there and it again looks proportionately far too small the whole body is just sort of a weird shape too and definitely doesn't appear to be as wide as it really should be especially when the gastralia or belly ribs are included too which makes these animals bodies appear very robust lots of other common Walking with Dinosaurs therapod issues are clear in this design too such as the pronated hands in reality theropods wouldn't have been capable of this position instead holding their for limbs with their palms facing inwards it's also just overall much too skinny and Shrink wrapped and as I've already noted many parts of its Anatomy needs some serious beefing up so what exactly happened with the skull shape well it's not entirely clear as it looks like they sort of just made it from memory without actually looking at a tyrannosaurus skull it's very weirdly blocky in shape and the snout is definitely Too Short in addition instead of having bosses above its eyes and a ridge along the top sides of its skull it's just just given a strange Ridge structure over its brows and going along towards its snout you see a lot of variation in the exact ornamentation of tyrannosaurus skulls in modern paleo art but this straight Ridge and lack of bosses is definitely not the way to go based on what we understand about the Bony skull Anatomy the nostrils are also positioned in the wrong place being too high up on the snout and the teeth look very odd mostly all being the same sort of size and shape despite Tyrannosaurus being well known to have a heterodon condition mean meaning the teeth are quite different in different parts of the mouth the teeth at the very front of the upper jaw are actually a lot smaller than the teeth further back and this just isn't represented in the Walking with Dinosaurs model at all some of the teeth further back in the mouth do seem to be a little bigger to be fair but there's not as much of a difference as there should be Apparently one of the main reasons for the T-Rex design looking like this is because the original model maker quit the project when the design was only half done and a second model maker then finished it off but both halves were proportions differently it would explain a lot about why the animal looks quite so weird here the integument of Tyrannosaurs and T-Rex in particular is obviously something that's been discussed a great deal in recent years with several shifts in thinking having occurred since Walking with Dinosaurs aired the general consensus now seems to be that T-Rex itself was a mostly scaly animal but since it evolved from Mostly feathered ancestors there's still the distinct possibility that it retains sparse filaments across its body prehistoric planet has a fantastic reconstruction of tyrannosaurus that shows this exact arrangement with very light feathery filaments evident on the skin the design also falls into another Trope common among older dinosaur reconstructions with very large and obvious scales present across the body as well as some almost elephantine like skin folds in places based on the few Tyrannosaurus skin Impressions we do have it seems that T-Rex actually possessed very small scales across most of its body meaning that from a distance the integrant would appear quite smooth and probably not all cracked and blocky like The Walking with Dinosaurs design there is the possibility that these animals featured larger potentially ornamental scales on their heads and faces though something I've discussed in previous videos then there's also the whole lip debate which I've spoken plenty about in my video covering this topic but it seems that the Walking with Dinosaurs design lacks proper lips as the upper teeth are still exposed when the mouth is closed I'd recommend watching my lip debate video for full coverage of this controversy the coloration of the Walking with Dinosaurs T-Rex is not too bad I like the striped tail and subtle reddish orange patch under the head and throat and it's certainly another quite recognizable design that's undoubtedly had some influence on later reconstructions in various media also that Beasts of the mesic Tyrannosaurus model with the walking dinosaurs colors is the greatest thing I've ever seen and I'm determined to one day get my hands on it next it's time to talk about that tongue I'm not sure why they gave the Tyrannosaur a sausage for a tongue but based on what we know about tongue mobility and dinosaurs it probably wouldn't have been anywhere near as flexible as it's shown to be here as I've mentioned in the episode 4 review a study from 2018 looked at the hyoid bones across different arkosaurus the bones involved in anchoring tongue muscles and discovered that most non-bird dinosaurs actually had hyoids more like that of crocodilians and not nearly as complex as those in modern Birds this suggests then that most non-bird dinosaurs probably had largely immobile tongues more like those of modern Crocs although derived on aisans such as ankylosaurs did apparently have quite elaborate hyoids indicating greater movement of their tongues so it therefore seems unlikely that Tyrannosaurus would have had a tongue that could curl up quite as much as is shown when it Roars in this episode upon introducing Tyrannosaurus Kenneth states that it is a 5ton 13 M long carnivore these dimensions are actually pretty reasonable although the 13 M length is on the Bigg bigger end of tyrannosaurus body length estimates while 5 tons is actually on the smaller end for Mass estimates modern body mass estimates using calculations from limb bones as well as digitized models generally put the adult T-Rex mass at between 6 to 8.9 metric tons however there's also a good deal of variation between the different specimens that are known of this dinosaur a study published in 2019 calculated the body length and mass of a particularly old and massive T-rex skeleton nicknamed Scotty which was found in Saskatchewan Scotty seems to have actually been even larger than the famous Sue specimen the most complete TX ever found and still a massive individual Scotty was found to probably have been 13 m in total length and to have a mass of 8.87 metric tons making this the heaviest Tyrannosaurus specimen known however it was also noted that Scotty probably had a lower standing hip height compared to some other more grile individuals that stood a little tall ER but were not as robustly built as Scotty again showing how much variation is known for this species this brings us to another topic of discussion on Tyrannosaurus that has been the subject of much recent debate the episode states that female Tyrannosaurus are larger than the males however this seems to be based on some evidence for sexual dimorphism in T-Rex that is no longer supported in the early '90s paleontologists surveyed the variations seen between All the known Tyrannosaurus specimens finding that two distinct morphs could be recognized a robust one and a gracile one they took this to be indicative of sexual dimorphism where one sex shows notably different anatomical characteristics to the other and concluded that the robust morphs represent females since the angle between the isia part of the hip that projects down and the tail vertebrae of these forms was greater than in the gracile morphs so they suggested this greater angle would have provided more space for eggs to have passed through and hence the robust morphs correlate to females building on this other paleontologists suggested that as had been claimed for crocodilians the first of the Chevrons the projecting bones underneath the tail were variable between Sexes too it was said that in females the first Chevron was placed further back and was shorter than in males again providing more space for eggs to pass however in 2005 a study investigated this hypothesis finding no statistical support for such variation between male and female alligators or other crocodilian species they then looked at Tyrannosaurus specimens and once again found no significant variation in the Chevrons suggesting that this was not a useful feature for sexing dinosaurs there has also not been any statistical support for the angle of the isio being an indicator nor for various other anatomical features suggested to potentially indicate sex also in 2005 though one particular specimen of tyrannosaurus was actually shown to be female a specimen known as B rex found in Montana was reported to have a type of bone tissue lining the interior marrow cavities of its hind limbs called meler bone which is also found in modern birds and provides a source of calcium for producing eggshells and as such is only present in bird bones when a female is ovulating the discovery of melery bone in bex's skeleton then suggests that this individual was a female that died while it was ovulating the suggestion that this preserved bone type is Del bone was somewhat controversial for a while however but more recent chemical analysis of the fossil has added further support to this interpretation still though the general consensus remains that evidence of sexual dimorphism among T-Rex isn't supported by good enough evidence and ideally we'd need many more specimens of these dinosaurs to have a reliable enough sample size to properly test the true significance of the variation in Tyrannosaurus individuals that hasn't stopped some paleontologists though with a now inFAMOUS paper from March of 2022 in which two new species of tyrannosaurus were named based on the argument that enough variation can be seen between all the different known specimens for them to be recognized as three separate species Tyrannosaurus Rex Tyrannosaurus vagina and Tyrannosaurus imperator a lot has since been said about this study and I also made a video on the situation back when it first came out but basically it doesn't seem like most paleontologists accept the argument made in this paper and the evence just doesn't currently seem good enough to split the genus into these three species that's not to say that there wasn't more than one species of tyrannosaurus that existed though just that the way these ones were established isn't that reliable death of a Dynasty shows T-Rex getting up to all sorts of things in this episode and featuring a whole variety of behaviors the really nice thing about this episode is that we don't just have T-Rex being a killing machine terrorizing every poor inhabitant of Hell Creek Walking with Dinosaurs does what it does best and and shows these giant dinosaurs as real complex animals going about their daily lives with the main Narrative of the episode following the reproductive cycle of these reptiles as they search for a mate do the deed and then care for their young I like that we get a good mix of tyrannosaurus being shown as an active Hunter while also opportunistically Scavenging when an easy meal is available as many of you are probably aware there was an old debate about whether T-Rex might actually have been an exclusively Scavenging animal well I say a debate but essentially it was just Jack Herer versus everyone else anyway all the various Arguments for a purely Scavenging mode of Life have been rebutted and we also now have direct evidence for active predation by Tyrannosaurus anyway with a broken T-Rex tooth crown having been found embedded in a hydrosaurus tail vertebrae and surrounded by healed bone showing without doubt that a T-Rex had bitten into a living dinosaur that managed to escape and heal so it's nice to see Tyrannosaurus actively hunting a hadrosaur in this episode we don't get to see how the male Tyrannosaurus took down the Triceratops it's shown feeding on but the hunting sequence as the mother T-Rex attacks the hyur reconstructs the theropod as an ambush Hunter quietly approaching the herd before there's a sudden burst of speed and it singles out one hyur in particular which it then knocks over and kills T-Rex has indeed been suggested by paleontologists to have been an ambush Predator although it's also possible that it was a long-distance stalker which used a final burst of speed to take down its prey the way in which the Tyrannosaurus kills the hosur here doesn't seem unreasonable at least and the detail of it Knocking the hosur down is quite interesting as paleontologists have proposed a hunting technique for a T-Rex attacking a Triceratops that they compare to cow tipping whereby they found that an adult T-Rex moving at moderate speed would have more than enough Force to knock over a large Triceratops now because it's Tyrannosaurus and everyone loves a good Tyrannosaurus study there have actually been a few papers looking at how exactly Tyrannosaurs would have defleshed carcasses and so we can say a bit about how it's shown feeding in this episode biomechanical analysis and study of microware on the teeth of allosaurus and Tyrannosaurs show that Allosaurus seems to have ripped the flesh off bodies by quickly retracting the head backwards in a sort of puncture and pull movement whereas Tyrannosaurs have been inferred to have predominantly engaged in what's termed lateral flexive Shake feeding similar to what crocodilians do where they shake from side to side to get bits of meat off when the mother T-Rex is shown feeding on the hadrosaur it does sort of look like it's using a quick backwards retraction of the head instead of shake feeding however when the male feeds on the Triceratops carcass earlier in the episode it looks like it pulls the flesh off to the side a bit Tyrannosaurs could probably have varied in exactly how they defleshed carcasses though and it's only a minor detail paleontologists have also noticed another pretty gruesome detail about Tyrannosaurus feeding though looking at Triceratop specimens in Montana they found that a lot of their Frills had tooth marks inflicted by T-Rex which seems strange as the Frills don't have much flesh so why would they biting there so much well none of the tooth marks had healed meaning they were all made on already dead individuals and a lot of the marks were deep grooves suggesting the Tyrannosaurs had been pulling on them so they hypothesized that these Tyrannosaurus individuals would have gripped the Frills of the Triceratops meals and pulled their heads off to get the Frills out of the way of the nice big neck muscles they even found more bite marks around the ball and socket joints of the Triceratops necks further supporting this idea so uh yeah it would have been an interesting thing to show in this episode that definitely wouldn't have upset any children watching I'm sure although to be fair spirits of the ice forest does show the polar allosaur straight up decapitating alosa so we know they weren't afraid to get pretty gory while hunting the hadrosaur the T-Rex is shown moving pretty quickly but this this is another highly debated aspect of the Tyrant King's biology while T-Rex has been found to be a very efficient Walker not having to expend much energy while it moved at slow speeds across large distances various biomechanical Studies have found that it could probably not run particularly fast likely limited to top speeds of around 27 kmph or about 17 mph while other estimates put it a bit lower more like 18 km/ hour or about 11 mph it also most likely wouldn't have been capable of sustaining these top speeds for very long at all another study has also found that Tyrannosaurs were pretty maneuverable compared to other giant carnivorous dinosaurs however being able to make faster turns so the depiction of tyrannosaurus running for a very short burst and not reaching particularly extreme speeds is probably pretty plausible based on our current understanding another of the Tyrannosaurus behaviors we see in this episode are these dinosaurs sitting down and sleeping we also get to see the mother T-Rex stand up from a sitting position a particular bit of behavior that has also been debated in the past because once again this is T-Rex and everything about it gets debated the animation in the episodes just sort of shows an awkward rising and a shifting of the back left leg as it gains balance but it doesn't look as though the for liims were used to provide support the use of the for limbs in helping a sitting Rex to rise has been suggested by paleontologists and indeed there may actually be a trace fossil that preserves the imprints from a Tyrannosaur getting up with the help of it arms a Sandstone block found in New Mexico and described in 2021 preserves what has been interpreted as a left footprint with only a single toe impression alongside a pair of parallel forearm prints which the author's hypothesize was created when a prone adult Tyrannosaurus got up from a quadrupedal position going by this interpretation it looks like the rising dinosaur stepped forward with its left foot while at the same time pushing down with its forearms to help it get up it's an absolutely amazing f if this really is what it preserves and supports the idea that Tyrannosaurs would have employed their forearms which were actually very strong in standing up death of a dynasty also features a T-Rex conflict when the female tires of her mate and drives him away we know that Tyrannosaurs didn't always get along with other members of their own species as there are many documented examples of various Tyrannosaur species with bite marks on their faces that most likely resulted from intraspecific fights the tyrannis s a specimen Sue which we mentioned earlier actually even has healed perforations at the back of its lower left jaw which were possibly inflicted by another Tyrannosaur and the specimen nicknamed Jane also has healed face bites suggesting that even juveniles fought with each other that is going by the interpretation of Jane as a juvenile Tyrannosaurus and not nanotyrannus as some continue to argue and which we'll mention a bit more later so although the conflict in this episode doesn't escalate to face biting it it is indeed another Behavior that's supported by fossil evidence the Tyrannosaurs in this episode also make a lot of noise with a variety of vocalizations being heard throughout as you can imagine this has once again been the subject of much discussion despite trrex being shown making lots of dramatic Roars with its mouth wide open this is no longer thought to be realistic for such dinosaurs instead non-avian dinosaurs likely made vocalizations more like crocodilians and perhaps some Birds prehistoric planet again features some much more plausible T-Rex sound design with lots of hissing and lowf frequency pulses not a mamalian like Roar as seen in Walking with Dinosaurs although I do really love the iconic sound of the Rex roar in the episode The Walking with Dinosaurs Tyrannosaurs do also make some fairly crocodilian likee hissing noises at certain points too although the unique sound producing organ of birds called the syrinx has so far not been reported from non-bird dinosaur URS the reporting in February of 2023 of an exceptionally preserved fossil larynx the voice box of the ankylosaur pinacosaurus has shown that these dinosaurs at least could in fact have used quite bird-like vocalizations these vocalizations could have been loud and explosive calls Modified by the specialized anatomy And although there's no direct evidence of Tyrannosaurs having such a larynx it is a possibility that other dinosaur groups had them and could make very complex noises the IDE AA of the long-distance calling that the mother T-Rex engages in to attract a mate is very interesting and study of the brain case and inner ear region in Tyrannosaurus suggests that they were adapted to pick up low frequency sounds as low frequencies can be transmitted across great distances it's therefore possible that these dinosaurs had hearing sensitive to lower frequencies in order to help in tracking the movements of prey or even for attracting and detecting mates so although the Roar sound design is not very accurate by itself the general idea of long-distance calling is actually somewhat plausible Tyrannosaurus is also shown to have engaged in Parental care with the mother T-Rex hunting for her Offspring and protecting them from danger there's not much direct evidence suggesting that Tyrannosaurs cared for their young but it's not out of the question either considering the inferred behaviors of some non-bd dinosaurs plus many bird and crocodilian species it does seem that younger Tyrannosaurs may have been feeding on different pray items to older individuals with a paper from December of 2023 describing a juvenile Gorgosaurus specimen that has the legs and bits of the tail of small oviraptorosaur hatchlings in its stomach suggesting preferential feeding on small fast prey meanwhile there's evidence for older Tyrannosaurs going after larger dinosaurs and so it appears that the juveniles and adults were occupying different ecological niches to avoid competing with one another seeming to indicate that the youngsters had to feed themselves and stay out of the way of adults which doesn't seem like evidence for prolonged parental Care at least not in later juvenile growth stages but it's still a possibility for very young juveniles as shown in the episode there's also a bone from a young T-Rex individual probably a subadult that has tooth traces on it from a larger Tyrannosaurus showing that sometimes the juveniles were not able to stay out of the way of the adults linked with the idea of Parental care is the debate over whether or not Tyrannosaurs may have hunted in packs the main line of evidence in favor of group living Tyrannosaurs is the presence of multiple individuals of the Tyrannosaur Albertosaurus in a bone bed in Canada individuals of different ages were present and this has been used to argue for pack hunting Tyrannosaurs apparently there's also a site where multiple Tarbosaurus individuals have been found together but it doesn't seem to have been published on and there's also a fossil trackway in British Colombia that preserves three sets of Tyrannosaur its tracks all walking together in the same direction the trackway is very interesting but doesn't by itself suggest coordinated pack hunting in these animals just an association of three individuals for a period of time other paleontologists have also criticized the evidence given for pack hunting from the associated Tarbosaurus and Albertosaurus skeletons plus all the media hype that was made to support it which is a whole other story they caution that an association of skeletons alone cannot be used to itely prove Cooperative pack hunting and many other factors still need to be considered what about the design of the juvenile T-Rex in this episode then we do have a few specimens of juvenile Tyrannosaurus although to no one's surprise this is also another aspect of T-Rex that has been heavily debated by paleontologists you may have heard of nanotyrannus before the genus name given by some paleontologists to certain specimens of small Tyrannosaurs from the hell Creek formation nanotyrannus was first named back in 1988 when scientists looked at a small Tyrannosaur skull that they thought came from a fully grown individual therefore naming it as a new kind of dwarf Tyrannosaur that coexisted with T-Rex well I won't go into every detail of the debate although perhaps I will in a future video if people would be interested in seeing that but basically the majority of paleontologists now support the classification of nanotyrannus as a juvenile Tyrannosaurus Rex this is because features of the small skull turn out to also be present in the juveniles of other Tyrannosaur species and a few other specimens that have been argued to be more complete anatran specimens most famously the specimen nicknamed Jane were demonstrated to not have been fully grown at the time of their deaths based on thin sections of their limb bones that preserve growth rings certain features of the skeletons that have been used by supporters of nanotyrannus to argue for its distinction have also been refuted by other researchers and shown to be quite variable characteristics of Tyrannosaurs in general or features that change as the animal ages still the debate continues and Nano tyrannus proponents continue to suggest new lines of evidence so then based on what we know of juvenile T-Rex how do the designs in this episode hold up the shape of the head looks like it's a little bit too blocky and robust compared to the surprisingly grile and long snouted skull shape we see in juvenile rexes and the bodies are also maybe a little too bulky T-Rex went through some quite incredible changes to its morphology as it aged developing deeper skulls and Jaws enlarging the ornamental features of its skull above the eyes and getting thicker as well as larger teeth the forearms were also relatively longer compared to the body size as juveniles getting shorter as adults and juveniles had relatively much longer lower leg bones than adults to suggesting they could run faster The Walking with Dinosaurs design does give them quite long and ungainly looking legs which is good but overall they're just a little too bulky a lot of modern reconstructions also give juvenile Tyrannosaurs at least a partial covering of feathery integrant despite the adults having a very sparse covering this isn't based on Direct fossil evidence but is inferred from the fact that giant Tyrannosaurs such as T-Rex evolved from feathered ancestors and because a feathery coat in juveniles would help keep them insulated at these small sizes whereas a fully grown Tyrannosaurus would probably be struggling to shed heat therefore as we also see in prehistoric Planet a coat of feathery filaments across the bodies of the juvenal is quite plausible so then Walking with Dinosaurs T-Rex is an interesting one obviously this iconic resident of Hell Creek just had to be included in the show and despite all the flaws with its appearance I'm glad it introduced the audience to such a variety of interesting behaviors many of which do actually still seem reasonable by today's standards one of the other other dinosaur stars of this episode is the Magnificent torosaurus a chasmosaurine ceratopsian known from the hell Creek formation as well as other localities across North America now as many of you may know there's quite a bit of controversy surrounding this dinosaur with the idea that torosaurus fossils might actually represent older growth stages of Triceratops having been proposed back in 2010 and some people still supporting this hypothesis today this hypothesis states that relatively very quick and quite atic changes in skull shape and features occurred later on in Triceratops growth resulting in changes such as massive holes technically termed parietal finestre opening up in the Frills of these animals Shifting the Triceratops morph into the torosaurus one well interwined with this controversy is also the question of whether torosaurus would actually even have been present at the time this episode is taking place right at the very end of the final stage of the Cretaceous a paper published in 2014 by the same authors who initially proposed the Triceratops torosaurus synonymy as well as others looked closely at the stratigraphy of the hell Creek formation and where within the formation various specimens of these ceratopsians came from what they found was that the two currently recognized Triceratops species actually didn't overlap in time with one species restricted to lower down in the formation and the other higher up suggesting that one of these species evolved directly into the other a kind of evolutionary process called anagenesis but there also seems to be some interesting implications for torosaurus here too although in this paper torosaurus is considered a morph of Triceratops the fossils that have been traditionally assigned to torosaurus all appear to come from lower down in the strateg graphy of the formation so it has been argued this shows that whatever the relation between torosaurus and Triceratops the torosaurus looking ceratopsians of Hell Creek were restricted to earlier on in this stage of the Cretaceous and would not have been around at the very end when this episode is set but then this becomes Complicated by the 2016 publication reporting the discovery of a torosaurus specimen that clearly states it was found in the upper third of the hell Creek formation showing that it lived much later than most other specimens of this dinosaur and quite probably could have been around at the very end this 2016 publication also argues against the 2010 suggestion that torosaurus is an older triceratops and indeed it seems that the majority of dinosaur paleontologist would agree these two dinosaurs are two different gener a 2012 paper presented evidence showing that they'd found specimens of immature and mature triceratops and torosaurus individuals and various other Publications in more recent years have argued against the hypothesis too it's still interesting though and certainly challenged our general idea of dinosaur diversity a paper from March of 2022 also presented some more evidence against the synonymy of these dinosaurs as well as evidence in favor of of torosaurus being around at the very end of the mrican stage this evidence came in the form of more torosaurus material from Canada that dates to the upper part of marrian aged formations here meaning torosaurus was still alive at the very end of the Cretaceous but all of this is to say that as far as we can tell for now having torosaurus in Death of a dynasty is still acceptable based on our updated understanding although they probably weren't quite as abundant or common in this formation as they're portrayed here based on the relative rar of their fossils compared to Triceratops moving on to the overall look of the animals shown in this episode it's actually not too bad and might be one of the better aged models in the series apparently they got the number of toes on the front feet wrong though as it seems only four toes can be seen despite ceratopsids such as this possessing five digits though the fifth digit didn't usually contact the ground the shape of the frill in this model is not too bad although it has very straight edges on all sides which actually seems to be somewhat of a very variable feature in this dinosaur with some torosaurus specimens preserving the Triangular bony growths on the outer margin of the Frills Bones called epiparietals whereas in others they seem to be completely absent or lost to be fair too in the specimens where these structures are present they're also not particularly obvious especially in comparison to other ceratopsian species with very prominent epiparietals still though it could have been nice to show some of these around the frill margin the very top of the frill is possibly a little too rounded in shape as well with some torosaurus specimens showing a slight concavity at the top here though again this is a bit of a variable feature with other specimens having quite a rounded margin the size of the nasal horn being relatively smaller in comparison to Triceratops is also portrayed quite nicely in this model but again this is actually perhaps surprisingly a fairly variable feature among the known specimens of torosaurus with very different shapes and sizes being preserved the brow horns are also quite varied in shape between different specimens too but in quite a few they seem to curve forward slightly so the Walking with Dinosaurs design might have them a bit too straight they also placed a little too far back behind the eyes in these models the skulls show that the horns actually projected from right above the orbits the skull of the Walking with Dinosaurs model is perhaps also a bit too short and should be lengthened a bit and as I've mentioned in the previous episode review the anatomy of orys and dinosaur cheek musculature has become a topic of discussion in recent years research published in 201 18 proposed that the traditional idea of muscle fibers stretching from the upper to lower jaw in various derived onisan groups including ceratopsians was incorrect and that instead of having this mamalian like Arrangement orys skins were more likely to have a sort of forward extending fan of muscle that's attached to the lower jawer at one end and to the cranium at the other underneath the flaring jugle or cheekbone so truly muscular cheeks in these dinosaurs that cover the entire extent of the back part of the mouth don't seem likely but it also doesn't rule out the possibility that thinner non-muscular cheek analoges could have been present as such structures make sense to keep food within the mouth when chewing as a consequence the fairly muscular thick cheeks in these torosaurus models might not be what these animals really had but again this is the subject of some recent debate the integrant of ceratopsian dinosaurs has in recent Years also come into Focus as a topic for interesting discussion this has been the result of some absolutely stunning fossils of Basil ceratopsians such as the remarkable cacasa surus from the early Cretaceous of Asia which is known from some absolutely beautiful specimens including one in particular that preserves a truly incredible amount of soft tissue along the top of the tail in this specimen is a series of bristle-like structures and have resulted in a lot of more recent paleoart going as far as to depict more derived ceratopsians including torosaurus itself with bristles along the tail too whether this is likely to have been the case remains highly speculative as for now cacasa orus is the only known ceratopsian to preserve Direct evidence for such integument and so we can't really say that the Walking with Dinosaurs torosaurus design should have bristles down the tail it is possible to make some inferences about other parts of the body and the integrants that would have covered it though limited sections of preserved fossil skin have been documented in a few derived ceratopsian species including Triceratops a review of our knowledge on ceratopsian integument published in August of 2022 found that the scaly skin anatomy of these dinosaurs was actually quite conservative and would have consisted of larger subcircular or polygonal scales which were then surrounded by many smaller and non-overlapping scales that were themselves polygonal there would likely have been variation between different taxa but it's probably safe to assume that torosaurus had similar scale patterning which unfortunately is not really portrayed in The Walking with Dinosaurs model instead showing them with quite wrinkled elephantine skin torosaurus is also shown to aggregate in herds in this episode which is consistent with our current understanding in of ceratopsian behavior there are quite a few bone beds containing multiple individuals of ceratopsian species recorded especially in Dinosaur Provincial Park in Alberta Canada where accumulations of many centrosaurus and styracosaurus fossils have been found these instances likely represent herds that were killed by severe flooding events as they tried to cross a river and some ceratopsian bone beds may even contain the remains of hundreds to thousands of individuals suggesting that at least some species came together in massive groups or they may represent a few Mass mortality events there's only one known Bone Bed containing multiple torosaurus individuals found in the latest Cretaceous of Texas this Bone Bed includes two adults and a juvenile based on the number of duplicate bones and so we can say with some certainty that these particular ceratopsians did indeed aggregate together though it's not yet possible to say if they formed massive herds like other species the fact that a juvenile was recovered with the adults also suggests some degree of parental care also supporting this behavior shown in the episode the colors of the Frills in these torosaurus models are very distinctive and have become quite iconic with their yellow and black false eye patterns this is obviously entirely speculative but it's a very interesting idea and very nicely demonstrates to the viewer the main function of the ceratopsian fril as a display structure this concept is again reinforced by the scene in which the competing males show off their Frills to one another even being shown to flush the skin with blood to create brighter colors again highly speculative and probably not all that plausible but it does illustrate the frill function the males then proceeds to engage in physical combat with each other interlocking horns and wrestling until one of their brow horns snaps however the narration also stresses that this is only a last resort and that in most cases visual display is all that's required to settle disputes which is again a very nice touch of realistic animal behavior this whole scene is actually still pretty accurate by today's standards with quite a bit of research having been done on the evidence for and bi mechanics of ceratopsian intraspecific combat particularly in Triceratops a study looking at how two Triceratops individuals would contact each other if they interlocked horns examined where the most likely places for injuries inflicted by this behavior on the skull would be and then surveyed various specimens they found that the injuries reported on actual Triceratop skulls do generally coincide with these predicted zones and so it's seems that horn interlocking as a specific bit of aggressive behavior between these animals did potentially occur more research has also looked at patterns of pathologies across ceratopsian skulls comparing the rates and locations of injuries on triceratops and centrosaurus interestingly quite different patterns were found between the dinosaurs with Triceratop specimens displaying many more lesions with evidence of healing on their sosal bones which make up the parts of the frill to the sides considering the very different arrangement of hor horns in triceratops and centrosaurus with two large brow horns in the former and very short brow horns but a massive nasal horn in the latter the researchers conclude that this difference in injury distribution is most likely explained by the lesions in Triceratops being caused by the brow horns of con specifics centrosaurus May therefore have engaged in a very different form of intraspecific combat perhaps mainly targeting the bodies of opponents instead of their heads or maybe relying on visual display More Than Physical aggression Triceratop specimens meanwhile have many cranial injuries consistent with the use of their horns in combat another study from April of 2022 examined a particularly massive Triceratops Horus individual from the hell Creek formation known as Big John analyzing a perforation on its right sosal this opening has irregular margins and indications of inflammation and was confirmed to have been the result of a traumatic event although the exact cause of this trauma can't be determined with with absolute certainty it is consistent with the shape and size of a Triceratops brow horn this injury in Big John also appears to have been inflicted from behind which is kind of sad so perhaps he was being chased off when a horn went through his thrill poor old JN anyway given the similarly large brow horns of torosaurus it's therefore not unreasonable to infer similar styles of intraspecific combat among these dinosaurs and so the portrayal of the fight in this episode seems to be pretty good the snapping of the brown horn is also actually supported by fossil evidence as there's a horn core pair probably from Triceratops in which the end of the right horn is gone and there's even some healing visible we also see a few juvenile torosaurus individuals in this episode the younger growth stages of the closely related Triceratops have been studied quite well with some amazing specimens of juvenile Triceratops known whereas only the one torosaurus juvenile from The Bone Bed I mentioned previously has been reported and it's only known from limb elements based on what we know of Triceratops youngsters derived ceratopsians appear to have gone through some fairly dramatic changes as they grew especially in their skulls they start off with tiny brow horns and a very small frill which is highly scalloped in juveniles as it's bordered by bony projections called epoxyalcohol merging into the nasal bone at a later stage and the brow horn cores change their direction of growth pointing forwards instead of being recurved plus the overall skull shape undergo a massive change becoming more elongated the frill also stays relatively small for most of the early growth stages only fully developing once the animal reaches about 75% of its adult body size again this is a good indication for the structures representing a sexual display structure involved in attracting mates as well as competing with Rivals as such a structure would only develop once the individual reached reproductive maturity going by what we know of Triceratops growth then the babies probably have Frills that are a bit too developed for their age as they already look like they're extended quite far back the Frills may also have possessed epoxyalcohols have been reported we can't say for certain the brow horns of the babies also look like they're placed way too far back as they should be right above the eyes not behind them so overall definitely not the worst dinosaur portrayal in this episode and a lot of the behaviors shown still hold up well based on what we know today it was also an interesting choice to focus on torosaurus instead of the much more wellknown triceratops and although Triceratops would probably have been a better fit for the episode it's still nice to give some attention to this other ceratopsian species having said that though Triceratops does actually make an appearance in this episode 2 it's just quite dead Kenneth explains that the male Tyrannosaurus has brought down a young triceratops and already I have to commend the episode for specifically stating that it's a young individual and including the EP ocials around the edge of the frill which as I just explained is indeed a feature only seen in younger growth stages so a very nice detail there obviously the range of behaviors for this species shown in the episode is well rather limited and mostly just consists of it being dead on the floor so we can't say too much about that we do have evidence that Tyrannosaurus did indeed feed on Triceratops though with a femur and a pelvis from the ceratopsians displaying bite marks that paleontologists have attributed to the teeth of T-Rex so as portrayed in the episode Triceratops was on the menu for Tyrannosaurus despite it presumably having been pretty formidable prey in terms of the overall appearance of this Triceratops it doesn't look too bad it's got pretty elephant-like skin again and it's difficult to see if it's got the corre correct number of digits on the four feet there might only be four instead of the five that it should have but I'm not sure as this episode is set at the very end of the Cretaceous right on the kpg boundary it would make this Triceratops process the later of the two valid named species Triceratops process seems to generally have a larger nasal horn compared to the earlier Triceratops Horus and so the pronounced nasal horn seen on the carcass is a good detail the brow horn placement seems to again be a little bit off being behind the eye instead of right above them and there are again some of the issues I've talked about many times before with the general Walking with Dinosaurs reconstructions namely a bit of shrink wrapping of the soft tissues and quite muscular looking cheeks the nostrils might also be placed a little bit too high up and close to the nasal horn but again these are all very minor nitpicky details depending on how old this juvenile is meant to be the brow horns should maybe also be a little more recurved though this could presumably have been quite a variable feature between individuals especially considering the variations seen in Triceratop skulls the curvature of the brow horns is a good detail too showing the change in growth direction as the animal has aged so yeah not a whole lot that can really be said about this poor triceratops and again it's not the worst reconstruction it would have been quite nice to see a bit more Triceratops action but at least there's a fair amount of interesting behavior shown with torosaurus there's another kind of theropod dinosaur featured in this episode to the dromeosaur in the original version of the narration for this episode at least they're only referred to as dromeosaur however in the accompanying books and other media they specifically said to be dromeosaur itself which creates some problems for the scientific accuracy the dromeosaur genus so far only known to contain the one species dromeosaur albertensis which was first discovered in the dinosaur park formation of Canada has probably not been found in the hell Creek formation where this episode is set now I say probably because for a long time it was apparently thought the various fragmentary bits of bone and teeth that looked a lot like this genus coming from Hell Creek were evidence that dryosaurus was present here and not just in the older dinosaur park formation however with the description of a new type of dromeosaur called Acura Raptor from the hell Creek formation in 2013 the authors suggested that the teeth coming from these younger North American rocks actually belonged to this new dromeosaur instead then of course there was also the 2015 description of the larger Dakota Raptor from Hell Creek adding to the known diversity of dromeosaur of this formation however recent developments have cast some doubt on the validity of dakotaraptor but in the dakotaraptor paper they state that dromeosaur is actually present from younger rocks dating to the time of deposition of this formation after all so what the hell Creek is going on here anyway dromeosaur is therefore possibly time traveling in this episode but the inclusion is understandable given that the two other txar I've just spoken about weren't named until long after Walking with Dinosaurs AED so if they wanted to include a dromeosaur in this episode at the time they were making it dryosaurus itself would be the safest bet so now that's out the way what about its life appearance in this episode well clearly it's a very outdated reconstruction by today's standards and once again it's a case of the show reusing a model of another animal and giving it a reskin as it's very obviously a differently colored Utah raptor model from giant of the Skies as such a lot of the same issues have been carried over from that design and you can refer back to the utar Raptor section from the giant of the Skies review for details but basically it should probably be fully feathered have the palms of its hands face inwards and not be pronated and the skull shape has also been said to be too robust indeed dromeosaur was a very different animal to the quite unusual Utah Raptor with its more Tyrannosaur likee skull shape as I explained in the episode 4 review video there are again also some issues with the shrink wrapping of the model where two little soft tissue is added to the Reconstruction resulting in skull openings being visible from the outside and an overall quite skinny appearance to the animal another aspect of dromeosaur paleobiology that we've encountered previously with utar Raptor's appearance in the show is the question of whether or not these animals were pack Hunters as we explained in the other video this idea of pack hunting Raptors is primarily based on the association of several donus individuals associated with the large orthopods tenontosaurus which was interpreted as evidence of group pack hunting by these smaller carnivores however this has become questioned in recent years with research such as a 2020 study looking at tooth carbon isotope content in large and small teeth belonging to donus finding that older and younger members of this genus were actually feeding on different things and therefore inferring that they did not engage in complex social group hunting like some mammals do instead an idea that has become more popular in recent years is the hypothesis that loose associations of dris may have sometimes come together and even cooperated to hunt prey when the opportunity arose as seen in modern reptiles such as kodo dragons but were mostly solitary animals to be fair though in this episode you only see a pair of dromeosaur attempting to attack the torosaurus herd and it does also give the sense that this might have been an opportunistic but perhaps temporary Cooperative hunt unlike the strict and complex social order depicted in the Utah Raptors this torosaurus hunting scene does ra another question though the dromeosaur attack the herd here under the cover of Darkness but would dromeosaur actually have been active at night well amazingly we might actually be able to answer this question research published in 2021 looked at CT scans to measure the relative sizes of the eyes and inner ear structures in almost 100 living and extinct dinosaur species in order to work out the probability of nocturnality what they found was that a certain species of small theropod from Mongolia called shivu was actually incredibly suited to low light levels and so was presumably nocturnal whereas many other extinct therapods including dryosaurus itself would not have had especially good lowlight Vision so were probably not nocturnal animals however dromeosaur did apparently have pretty good hearing which would make sense for a predator but it was seemingly much better suited to hunt in the daytime still though that's not to say they probably wouldn't have hunted at night if they had the opportunity but it's just pretty amazing that pen ologists have been able to work out what time of day these dinosaurs were active so that probably covers the major accuracies and inaccuracies to do with the dromeosaur in this episode a lot of which are shared with the utar rapor reconstructions again I do quite like the coloration chosen for these animals which make them look very distinct from the utar Raptor with the Striking red segments of the tail and the very creepy looking green eyes I'm not actually sure if these eyes even have pupils in them though or if they are there they're very small which is interesting at least at least they don't have vertical slit pupils though as this type of pupil shape is generally only found in small predatory animals that hunt very close to the ground such as many small cats as they help in judging distances from low Heights there's also the nice detail of a nictating membrane in the eyes of the dromeosaur here just a cool little thing to include in the animation also featured in this final episode is one of the most famous armor dinosaurs of them all the iconic ankylosaurus itself this dinosaur is of course known from the heal Creek formation and so is indeed in the correct time and place for this episode and the most notably inaccurate thing about the animal is probably its overall appearance the body shape of this dinosaur is quite noticeably round in the depiction shown here but in reality it would have looked a lot flatter and held itself closer down to the ground the skull shape also seems to be quite off being not nearly as triangular or flat as it should be additionally the cranial ornamentation is very different to what we know it should look like based on the skulls found of this dinosaur with tile-like polygonal bony plates technically known as capitula covering most of the top of the skulls but any obvious capitula appear to be missing from the walking dinosaurs model instead giving it a much smoother appearance The prominent horns on the skull of Ankylosaurus are also somewhat understated in this model with the horns projecting from the top and back of the skull termed the sosal horns and the ones projecting from lower down the quadrat jugle horns definitely seeming a bit too small and conical compared to to the large quite broad structures they really were the tips are also quite a lot blunter than they should be but there's an interesting suggestion made in a paper published in 2017 that notes how in larger specimens of both eilis and ankylosaurus the horns become blunter at the tips and so this condition may represent an older growth stage just an interesting hypothesis to consider but yeah the horns and head of this model are still way off the arrangement of the Bony armor across the body is another point of critique that that can be directed at this reconstruction although it's understandable that this armor Arrangement is now considered outdated seeing as this has been a subject of quite a bit of uncertainty in the past ankylosaurus bony armor technically known as osteoderms have never been found in complete articulation with each other and so the patterns in which they were situated across the back sides tail and neck of the animals is up for interpretation the most recent up-to-date interpretation of the armor Arrangement was published in 2017 by paleontologist Victoria Arbor and Jordan Malon who used comparisons with related species to establish the most likely arrangement of the osteoderms as well as changing our understanding of Ankylosaurus body proportions compared to previous reconstructions this figure from that paper very nicely shows how the Bony armor is most probably to have been positioned with quite big spacing between the osteoderms and not as many rows down the back as in The Walking with Dinosaurs model The Walking with Dinosaurs model also shows the dinosaur with quite weirdly narrow OST odms whereas they should be a bit broader and on the neck there should be two structures called cervical half Rings bands of bony armor that were situated across the top of the neck but to be fair these half Rings weren't actually considered to have been present in analaura itself until this 2017 paper even though they'd been known about long before instead being interpreted by previous authors as more like quarter rings with a gap down the midline anyway moving to the most famous part of anarosa anatomy the tail Club perhaps surprisingly this is actually quite a poorly known part of the species with just one specimen including a part of the tail Club handle as well as the knob interestingly despite ankylosaurus being the largest of all the ankylosaurs it doesn't seem to have had an exceptionally large tail Club when compared to smaller bodied relatives likely indicating that there was an upper limit to the size of these structures that could actually be supported by the tail vertebrae the shape of the only known knob from anosa shows that the Walking with Dinosaurs model is a bit off off though as the knobs appear to project out to the sides a bit too much whereas the fossil clearly shows a very different shape the Walking with Dinosaurs reconstruction seems a lot closer to the club shaped scene in eilis or perhaps anodontosaurus so maybe was based more on those again though to be fair the amount of individual variation between the tail clubs of anarosa cannot be known since only this one specimen has been recovered so far I do also like how stiff the end of the tail just before the club starts is in the animation of this animal as this part of the taale was significantly strengthened with the vertebrae all fused together and stiffening rods composed of ossified cartilage acting to make this a very rigid region which is shown quite well here another nice detail shown in this episode concerns the social habits of Ankylosaurus generally it's accepted among paleontologists that ankylosaurs would have been rare components of their ecosystems and were probably not particularly social group living animals as they're generally rare as fossils and usually only ever found as single isolated individuals not making up bone beds there is the exception of pinacosaurus from inner Mongolia however which is known from a locality where four juvenile individuals were found associated with each other leading an kosur workers to suggest that perhaps at least some of these dinosaurs formed small groups as youngsters death of a dynasty is therefore probably pretty accurate in showing analaura as mostly solitary as well as briefly interacting with a single other individual this also brings us to another interesting aspect of anarosa paleobiology which has actually been the subject of a recently published study from December of 2022 This research also led by Victoria Arbor examined the holotype specimen of the analid zul cruy vastator from an older formation in Montana and discovered evidence to suggest that these dinosaurs may actually have used their tail clubs for intraspecific combat meaning they were utilized when individuals of the same species were competing for territory mates or other resources by slamming them into each other's sides and producing distinctive injuries on their osteoderms the paper therefore suggests that sexual selection and intraspecific combat were the main drivers of tail Club Evolution and that Predator defense would have been a secondary function that didn't have much influence on the actual development unlike what is implied in the episode broken limb bones seen in Tyrannosaurs obviously cannot be said to be the direct consequences of interactions with ankylosaurs but it's of course still possible that these armored dinosaurs would use these formidable weapons as Predator deterence if they were faced with such a situation as that shown in this episode so ankylosaurus is another incredibly iconic and famous dinosaur that was definitely a good idea to include in this episode and its portrayal while being somewhat strange in overall appearance is quite realistic and it feels like a real animal reacting to the circumstances it's in which in anatosaurus case is basically smash everything death of a dynasty also features a dinosaur species referred to as anat Titan this is actually a name that that is no longer in use for this animal as it's argued to be the same thing as Edmontosaurus and since Edmontosaurus was used as a name before anat Titan it takes priority over it I've always thought this was a bit of a shame though considering that anat Titan translates to Titanic duck which is just brilliant but anyway the taxonomic history of Edmontosaurus is a complete and utter mess so I won't go into details but for technical reasons the dinosaurs in this episode that are called anatot Titan should actually be Edmontosaurus an ens as this is the species reported from the hell Creek formation calling them an ATO Titan in this episode is excusable though considering that anat Titan was named in 1990 and the debate over the name then took off mostly in the early 2000s and even continues today in terms of the overall appearance these Edmontosaurus models are looking a little dated now there are all the usual issues again with some degree of shrink wrapping of the soft tissues and this seems to be especially noticeable in the neck which just looks very weirdly thin and weak we we actually know quite a lot about the life appearance and the extent of soft tissues of Edmontosaurus because incredibly we have a few mummified specimens of these dinosaurs despite the name these specimens are not true mummies instead it's more of an informal term to describe an exceptionally well preserved fossil that includes fossilized skin and possibly other soft tissues these animals became preserved like this when they died and then dried out and desiccated with all the skin and soft tissue becoming hardened then when the carcass was buried all of these hardened tissues were preserved instead of decomposing and were also replaced by minerals they became fossilized so what did these Edmontosaurus mummies tell us about these animals well firstly they weren't actually as plain in terms of hydrosaurus as the Walking with Dinosaurs models make them look many hydrosaurus are famous for having extravagant bony crests on their heads probably the most famous example being Parasaurolophus but Edmontosaurus was for a long time thought not to possess anything like like this that was until 2013 when a mummified specimen revealed that Edmontosaurus regalis which is the slightly older species actually had a fleshy comb likee structure on its head sort of like a cockrel although it's not confirmed to also be present in Edmontosaurus an ekens which is the species in this episode it is a possibility that it would also have possessed some kind of similar soft tissue structure on its head but again this is a revelation that was made long after the episode aired so it's understandable that no such Crest was included on the model the head as a whole also looks very weirdly elongate and flattened which may also be the result of not enough extra soft tissue around the head and neck but it does also look like they just got the skull shape a little bit wrong it also shows the snout of this animal as being quite flat and wide at the front giving it a sort of spatulate shape this is the classic duck bill look that explains the common name sometimes given to the hydrosaurus the duck build dinosaurs looking at the skull alone you can see why this nickname has stuck as it appears that the end of the snout is indeed quite spatulate in shape however it turns out that this is not really the true shape of the hydrol mouth since there would also have been a ramtha attached to the end of the premaxillary bones at the tip of the snout a kind of beak tissue this beak extension can be seen particularly well on a specimen on display at the Natural History Museum of Los Angeles County which preserves a natural mold of the internal surface of the beak extending from the edge of the primax and which clearly shows that instead of the classic duck bill look these d dinosaurs had downturned shovel-like beaks which seem ideally suited to cropping vegetation The Walking with Dinosaurs models look like they might almost have the beginnings of a small downturned beak but really they should be much more extensive and they shouldn't appear duck build at all the for liims and hands of these models also look disproportionately bulky compared to the rest of the body when in fact they were quite slim compared to the hind legs it's quite hard to tell but it does look as though the hands themselves show at least some of the digits as being enveloped in a fleshy covering however it seems as though there are two separate hoof likee structures on each hand and again the hands are just ridiculously Broad and robust which looks very strange when compared to what the fossils actually show two of the so-called mummified specimens that have been known about since the early 1900s do actually preserve some of the soft tissues around the digits showing that digits 2 3 and four were held together in a sort of fleshy Mitten so really this probably should have been taken into account for The Walking with Dinosaurs reconstruction however since the episode aired another mummified specimen has been found nicknamed Dakota which shows even more clearly what the hands would have looked like in life the third and fourth digits were completely encased within the flesh metan which had a single hoof-like nail at the tip while digit two on the inside of the hand is partially included within the Mitten but also projects out while digit five on the outside of the hand projects from further up the hand and there's no digit one at all looking at the walking with Dinosaurs design it seems that digit 2 is projecting from higher up than digit 5 so that should actually be the other way around and then digits three and four seem to be separate with nails on both digits whereas they should actually be fused it also sort of looks like they may have added in an extra digit for some reason as the digit four on the model seems to be particularly wide almost like there's another digit inside the skin anyway it's pretty cool that we can now be so nitpicky over this design since we have these incredible Edmontosaurus mummies that tell us so much about how these extinct animals really looked we can even reconstruct what the scale patterns would have been like thanks to such amazing fossils the skin of Edmontosaurus ancens is especially well known and across most of the body comprises cluster areas with two types of basement scales there are smooth and polygonal scales that form clusters within a basement of small and pebbly scales towards the underside the scale clusters are small and arranged longitudinally and towards the upper side sides the Clusters are larger the top surfaces of the forearms are then covered by large polygonal scales and the underside by the PE basement scales obviously the resolution of the Walking with Dinosaurs models is not exactly good enough to really see the close-up texture of the scales but something that's notably missing from the design is a row of midline feature scales running from the base of the neck to the tail these scales are quite large and rectangular in Edmontosaurus and each correlates to the tip of the neural spines of each vertebrae it's quite a characteristic feature of Edmontosaurus that was known about at the time of walking dinosaurs production so it's a little odd that they weren't included the herding behavior shown in this episode is indeed supported by fossil evidence with bone beds similar to the ones known for ceratopsians also having been found for Edmontosaurus there's an absolutely huge concentration of Edmontosaurus and ens bones at a site in eastern Wyoming where at least 13,000 individual elements from these dinosaurs have been found based on extensive analysis of the site and the preservation of the fossils paleontologists have concluded that the Bone Bed results from a single Mass die off of many Edmontosaurus individuals in a catastrophic event again indicating a tendency to her together so then Edmontosaurus or anatot Titan was another good dinosaur species to include in this episode being an iconic resident of the latest Cretaceous North America however it's definitely one of the poorer reconstructions in the episode in terms of anatomical accuracy and a lot of the not so great parts of its design could actually have been avoided if more attention had been given to the mummified specimens which again have been known about since 1908 still I suppose they were trying to make it specifically anatot Titan which at the time was considered distinct to Edmontosaurus and so maybe that can explain some of the decisions plus it does also seem to be a slightly modified reuse of the Iguanodon models from previous episodes which also explains things a bit I do like the coloration given to the animals though the patterns are pretty intricate so clearly a lot of effort was put into this part of their look and it gives them a distinctive but still naturalistic appearance another dinosaur that makes a very brief appearance in Death of a dynasty is the little neon aisan species that's hunted by the dromeosaur at the lake and although no reference is made to them in Kenneth's narration the walking with Wiki suggests that they may be intended to represent the genus thesca surus whatever they're meant to be the Reconstruction is another case of Walking with Dinosaurs reusing models as they seem to be identical to the so-call orania that feature in The Ballad of Big Owl which aired in December of 2000 and which should now actually be called nanosaurus and it also looks like it's the same model as the dryosaurus that appears in episode 2 anyway fesal asaurus is indeed known from the hell Creek formation and a good deal is known about its Anatomy thanks to the relatively complete fossils assigned to this dinosaur it was even thought that a fossilized heart of this species had been found in one specimen however it turned out that it's probably just a concretion not a preserved organ however in April of 2022 an incredible fossil of a fcala surus leg with skin preserved was announced which has yet to be properly described but was also featured in the BBC documentary Dinosaurs the final day The Walking with Dinosaurs models again have many of the classic issues with their designs looking very skinny and having pronated hands and not looking quite as long in the Torso region as thesca surus actually was the tail also looks a little bit too short the skull shape seems too deep and not as Elon as the complete skulls known for thescelosaurus and many reconstructions now also give thescelosaurus and other neon aisans a coat of feathery filaments since the discovery of kulinda dromius in 2014 seems to suggest that some of these dinosaurs possessed such integument the fcala orus leg preserved with skin does show it to be entirely covered with scales though suggesting that the hind limbs of these dinosaurs were at least scaly not feathered a recent paper from November of 2023 has also found evidence to suggest suggest that thescelosaurus had specializations for borrowing so their real behaviors would probably have been very different to what's shown in the episode there are of course also a few non- dinosaur animals featured in this episode including the ashd darkid terrasaur kettle quas well at least it's supposed to be Kettle quas but it really doesn't look like it at all it's also questionable as to whether Kettle quas should even be here at all as it's not actually confirmed to have been present in the hell Creek formation in fact hardly any terrasaur material has been recovered from Hell Creek but a single vertebra from the neck of an asz darkid was described in 2006 some have therefore taken this to indicate that kettle qualus was present in Hell Creek but the exact identity of this isolated vertebra down to the species level is still unclear also it was first found in 2002 so Walking with Dinosaurs may actually have predicted the presence of ashd darket here it's not entirely unreasonable to infer the presence of these parasaurs in hell Creek however since Kettle koalas is known from the same age at the very end of the Cretaceous but from further south in America its fossils have been found in the Havalina formation and overlying black Peaks formation which both outcrop in Texas and they are included in what has been termed the Alamosaurus fora this defines the latest Cretaceous terrestrial vertebrate fora that can be found in Utah New Mexico and Texas while the so-called Triceratops forna occurs in Canada Montana and Wyoming it's a sort of north south divide between two different fornal provinces with different species occurring in each one despite living at about the same time though there are also some crossovers anyway Kettle koalas being part of the Southern Alamosaurus fora doesn't necessarily mean it wasn't also present in the more Northern regions of prehistoric North America too considering it might have been able to fly across these distances but for now we just don't have the direct fossil evidence for it being here the Reconstruction of this Kettle qualus is very bizarre and it just looks as though they've repurposed the oracus trop naus model from giant of the Skies overall it looks nothing like an asz darked which are notable for their long necks relatively small bodies and massive skulls none of which are reconstructed very well at all in this model it also appears a bit too small relative to the environment when it's on the ground with estimates for the larger Kettle koala species putting its wingspan in the range of about 10 m the narration does mention that it's a 13 M Giant which is probably a slight overestimate and once it takes off the wings do look pretty large but I think the proportions of the model on the ground unell quite how big Kettle katas actually was this reconstruction shows it walking in a very hunched slow fashion however ASD darked terasa stood much more upright than this and an ASD darked with a 10 m wingspan would likely have stood about 3 m tall at the shoulder they were also apparently very capable Walkers when on the ground one of the biggest errors with with this reconstruction is the inclusion of teeth in katalis it's hard to see in the actual episode but the model does actually possess teeth which is very bizarre as azd darkid are well known to have completely toothless beaks the skull shape overall is not at all how it should be with ASD darkid skulls being much deeper towards the back and thinning out to a sharp tip of the front additionally while this model does at least attempt to give Kettle qualus a Crest it's not the right shape a few skulls that have been assigned to the smaller of the two kettle quala species Kettle quas Lon named in 2021 do preserve parts of the headrest and show that they were sort of rectangular in shape and positioned further down the skull than the eyes although you do see a lot of variation in Crest morphology in modern reconstructions of this animal since it's not completely preserved and so possibly was extended further than the fossils show whatever its true shape though it's very different to the conical Crest that projects up and back from behind the eyes in the Walking with Dinosaurs reconstruction there are again many of the other issues with terrosaur that Walking with Dinosaurs has and that I've discussed at length in previous episodes such as a bit of shrink wrapping soft tissues the wings folding in from the sides instead of the back the hands not being rotated back enough when on the ground and the wing tips possibly being slightly toop pointed the episode also shows Kettle quattas dip feeding as it swoops down over the lake to pluck a fish out of the water by dipping its head down well the Ecology of giant as darked parasaurs such as Kettle koala has been the subject of much discussion in the past couple of decades and I've also talked about it myself in my three-part series on these parasaurs from a few years ago based on evidence from the distribution of ASD darked fossils trackways showing they were capable Walkers their long Limbs and the anatomy of their skulls and necks paleontologists have argued that these parasaurs were most likely terrestrial stalkers spending much of their time walking about on the ground and opportunistically feeding on vertebrate prey items however before this shift in the interpretation of asz darked ecology it was generally thought by various terasol researchers that the long necks of these flying reptiles were used to pluck prey from the water's surface without having to risk damage to the wing tips however it turns out that the necks of these parasaurs were not nearly flexible enough for the movements needed to dip feed being unable to bend underneath and behind the body as shown in the episode they also were very unlikely to have been skim feeders another common old suggestion for their ecology as they the necessary specializations of the lower Jaws or neck for this highly stress inducing Behavior so the feeding behavior shown in this episode is quite outdated and our understanding of how Ash darkid lived has changed significantly since it originally aired another pretty outdated part of this Kettle koala sequence is when Kenneth says for the last 20 million years these flying reptiles have been in Decline now these 13 M Giants are the only ones left and the Skies of the future belong to the birds that already flourish around him this reflects a view of teral evolution that has in recent years started to be overturned by newer evidence showing that these reptiles were not actually on the cusp of Extinction towards the end of the Cretaceous it had been thought that the azd darkid were the only terasol left at the very end of the Cretaceous Period While most other Cretaceous terrasur lineages had died out by the final stage the mrican however fragmentary discoveries from America and fossils from the late marrian aged phosphates of Northern Morocco now demonstrat that in addition to ashd darkid tanod doned and ncaids also made it to the very end of the Cretaceous additionally in Morocco these parasaurs were still pretty diverse representing at least seven different species across those three families they also occupy different ecological roles and display diverse morphologies indicating that the idea of their dying out was the result of biases in the fossil record since terrasur remains are generally quite rare anyway and just hadn't been documented at the very end of the cretacious an overall reduction in terrasaur diversity had still occurred however since many groups seem to have suffered an Extinction around the middle part of the Cretaceous Kenneth also hints at another now contested idea that birds were out competing terrasaurs taking over their ecological niches and causing their decline this idea has also been overturned in the last few years with more fossil discoveries from Morocco showing quite a different picture it had been thought that small parasaurs became very rare in the late Tous with mostly very large species being found from this time and it was therefore considered to be due to smaller bird species taking over the niches that were once occupied by smaller terrasaurs in the Jurassic and early Cretaceous however an analysis of terrasaur fossils from the kemm group of Morocco which dates back to the early part of the lake cretaceus shows that many very small parasaurs were actually present here alongside the giant forms they just hadn't been collected yet and so their apparent absence in the Lake Cretaceous is due to sampling bias all these small terasa remains turn out to be from juveniles of larger species not adults of small species so what appears to have been happening is that terrasaurs in the lake Cretaceous extended their size range instead of just switching to large and giant sizes this means that the niches previously occupied by small terasa species weren't being taken over by birds but instead by the younger life stages of large parasaurs a concept known as ontogenetic Niche partitioning where the juveniles have a very different ecology to the adults so all this is to say that terasa were doing a lot better than we had realized towards the end of the Cretaceous and were not already on their way out when the kpg extinction occurred though they were apparently reduced in diversity compared to earlier on in the mesic kettle qualus is therefore another interesting addition and at least we do get a terrasaur in the episode but the Reconstruction is definitely one of the poorer ones in the series and our understanding of as darket ecology as well as terrasaur Evolution has moved on significantly in the past 24 years one of the other animals in this episodes that actually gets a fair bit of screen time is diodon a Cretaceous mammal the episode states that diodon is a marsupial which isn't technically true but also not far off as it's a metapan the larger more inclusive group that contains marsupiales plus various extinct lineages of marsupial like mammals it is in the correct time in place for this episode with remains of this mammal having been found in the hell Creek formation as well as other late Cretaceous North American formations Kenneth States here that at 10 kg this is about as big as Cretaceous mammals get well there's a bit to unpack here recent body mass estimates for diodon put it at around 5.2 kg for adult individuals so less than the figure given in the actual episode but still in the range of mammals such as the Virginia aosom and American badger however there were some other Cretaceous mammals that got larger than this the species rapino mamus robustus was first named in 2001 and was found in early Cretaceous aged rocks in China this species which was a more basil kind of mammal compared to diodon was also about the size of an osum however in 2005 a second species was described Rino mamos giganticus which had a 50% larger skull size and was calculated to have a mass of between 12 to 14 kg with a total body length of more than a meter additionally this 2005 study reported on evidence for rapino Mammoth having fed on juvenile dinosaurs with tacosaurus bones present inside the rib cage of a rapino mamus robustus specimen an absolutely incredible Discovery published in July of 2023 also shows more evidence for rapino mamus and tacosaurus interactions preserving two skeletons intertwined with one another with the mammal seemingly attacking the dinosaur the animals were preserved within a volcanic debris flow that rapidly inms the peir freezing them in time in their final struggle it's got to be one of the most mind-blowing fossils ever found and shows that Cretaceous mammals were not all small timid animals living in the shadows of dinosaurs despite death of a dynasty somewhat portraying them in this way there are a few other Cretaceous mammals that likely got pretty big too potentially even larger than rapino Mammoth so the statement that 10 kg is about as big as Cretaceous mammals get is quite outdated the overall appearance of diodon in this episode has some clear influences from Tasmanian devils plus a bit of opossum and it has a very Badger likee coloration at the time of walking with dinosaur's production most of the fossil material known for diodon consisted of isolated teeth bits of Jaws and some rare skull bones considering that diodon is related to mupi ands that the anatomy of the dentition was observed to be similar to some of the specializations seen in the Tasmania devil it's therefore understandable that the design was based on such organisms since 1999 more remains of diodon have been found including some almost complete skulls described in 2016 these skulls show that diodon actually had a surprisingly High bite force and may have been one of the first thean mammals to become Duro fagus feeding on hard food sources death of a Dynasty shows these mammals to be opportunistic scavengers feeding on Tyrannosaur embryos as well as a torosaurus carcass and the analysis of the skulls show that this is actually quite likely with diodon potentially being a powerly biting predator and scavenger the high bite forces would have enabled these mammals to crack into bone as well as crunch down on the shells of invertebrates or perhaps Turtles however they didn't have all the adaptations of more specialized vertebrates that feed on Bones the paleontologists also suggested that diodon would feed on insects and perhaps plant matter to supplement its diet however there has been some debate in the past couple of decades over the Ecology of these mammals other paleontologists have argued that the family diodon belongs to the stodd were actually semi- aquatic based on isolated Bones from the Tails and feet that have been found in late Cretaceous deposits in North America other researchers have pointed out that these isolated remains are only referred to staged doned because of their size however and can't actually be assigned to diodon or relatives as they were not found alongside diagnostic remains Additionally the argument from the foot bones for an aquatic habit was based on the interpretation of these elements as enabling greater flexibility in the feet which was suggested to help them paddle however others have argued that the features of the foot bones instead suggest there was increased rigidity here and they were therefore better suited for digging there is apparently also a relatively complete diodon skeleton found in Hell Creek that supposed edly shows it to have had a fairly otter likee body but it doesn't seem like anything's been published on it yet at least that I can find I would be very interested to know if anyone can find out anything about it though there's also a 2014 paper that finds diodon to group with semi-aquatic species but again they seem to base it on those isolated bones that cannot be definitely associated with the cranial remains and so cannot actually be identified so D alidon's reconstruction in this episode seems to have aged quite well at least depending on whether or not it turns out to have been semi-aquatic it does sort of fall into the classic portrayal of mammals as hiding in the shadows of dinosaurs but it does also show quite nicely how successful mammals really were during the mesic going after Tyrannosaur eggs and opportunistically Scavenging on carcasses another mammal is very briefly shown in this episode 2 as one of the carcasses near to the volcanic vents where the male Tyrannosaurus goes to scavenge this is said to be the genus purgatorius on the walking with with Wiki and indeed it does look like that's what it meant to be going by the design purgatorius is actually a pretty significant animal as is possibly the oldest example of a primate ancestor first being described in 1965 based on teeth found in very early paleocene deposits as well as the hell Creek formation leading the initial describers of these mammals to think they were around in the latest Cretaceous seven different species of purgatorius have now been named and more recent dating of the the precise part of the formations that their teeth came from have since shown that the oldest Purgatory species were not actually from the Cretaceous but instead lived less than 200,000 years after the Cretaceous paleogene boundary this is still very very close to the Cretaceous in geological terms however and a recent paper from 2021 has argued that these mammals most likely did originate in the Cretaceous considering there are multiple species that lived so soon after the boundary so for now we can say it's still plausible for there to be a purgatorius like mammal in this episode considering that purgatorius is only known from teeth jaws and ankle bones not a whole lot can be said about its life appearance but the ankle bones indicate it was adapted for climbing trees and it probably looked something like a tree shrew so the body in Walking with Dinosaurs seems like a reasonable reconstruction also featured in this episode is a prehistoric crocodilian only referred to in the actual episode as a onton crocodile but named in the companion books and media as dinos sucus having this Croc be dinos sucus creates a few problems for the accuracy of the episode most notably due to the fact that dinos sucus is not known from the hell Creek formation and actually lived between about 82 to 73 million years ago long before the time this episode is set but if you've seen my previous Walking with Dinosaurs reviews then you know that time traveling prehistoric animals are nothing new in this series so how does the reconstruction hold up looking at all of the different fossils known for dinos sucus it's possible to build up a fairly complete reconstruction of its skull although for many years reconstructions of this animal were often based on an erroneous plaster model that contained a few pieces of actual fossil material displayed in the American Museum of Natural History the real dinos sucus looked quite different this model had been heavily based on the skull dimensions of the Cuban crocodile however dinos sucus is now understood to have been an alligatoroid and so wouldn't have just been a scaled up crocodile dinos sucus in fact had quite a unique skull with long and robustly constructed Jaws notably deep upper jaws and when viewed from above shows a clear lateral expansion around the area of the nasal openings the Jaws are also quite u-shaped at the snout as in other alligatoroids looking at how the jaws and teeth fit together it also seems that only the fourth tooth back from the front of the lower jaw would have been exposed when the mouth was shut while all the other the teeth on the lower Jaws were hidden so looking at the Walking with Dinosaurs dinos suus design there are clearly some issues the tip of the snout shows interdigitating teeth with those of the lower Jaws being visible with the mouth shut more like the condition in crocodiles rather than alligators the Jaws are also not nearly broad enough for dinos sucus and they seem to lack the lateral expansion around the nasal openings plus the one ton statement for dinos sucus is a bit of an underestimate with Mass estimates for the alligatoroids ranging from 2.3 metric tons up to potentially as much as 8.5 metric tons however I've also seen it stated in a few different places that the crocodilian scene in Death of a dynasty better matches the prehistoric gerial relative theorosa orus despite all the official media stating it to be dinos suus theorosa orus has indeed been reported from the hell Creek formation but seems to be fairly rare it was initially recognized from the formation based only on some remains that had a few similarities to the species but these fossils were not figured anywhere and it wasn't until 2016 when an abstract was published describing an Associated skeleton that we could be a bit more certain that something like theasaurus was really present here however a precise identification of the crocodilian could not be made and so the authors simply refer to it as a gav alloid consistent with the morphology of theasaurus so maybe it's here or maybe it's a different but similar species it did apparently get quite big though with the vertebrae indicating a substantially larger body size than the other crocodilians in the hell Creek formation based on what we know about the skull Anatomy from more complete remains of theasaurus that lived later during the Paleo scene the snout would still be a bit too robust in the walking of dinosaurs reconstruction and the snout tip is too expanded but overall it does seem to be a much better theasaurus than dinos sucus there's yet another reptile that makes an appearance in this episode 2 a species of Cretaceous snake although it's live acted by a red tailed boa constrictor the walking with Wiki states that the old Walking with Dinosaurs website names it specifically as Dinia patagonica well some issues arise there as Dinia lived much earlier on in the late Cretaceous than this and as you can probably guess by its name its fossils are known from Patagonia not North America there are some limited snake fossils known from Hell Creek though with the spe kerberus robustus being named in 2012 based on vertebrae although it is now thought to be a basil member of the derived snake group in 1989 long before it was given a name it had been referred to as an indeterminate member of the boa family so this probably explains the depiction of the snake in this episode using a modern boa the snake is shown to use infrared sensing having pit organs that enable it to detect Warm Bodies this is entirely speculative for this Cretaceous snake and probably quite unlikely considering that in modern groups infrared sensing appears to have convergently evolved in boers pythons and pit vipers and therefore probably wouldn't have been present in a common ancestor of these lineages however given that at the time it seems there was good evidence for this being a Hell Creek Bower the inclusion of this ability is understandable there's also a random therapod carcass in this episode in the same scene as the purgatorius where the male tyrannosaur goes to scavenge around the volcanic vent it's not really clear at all what this is meant to be but perhaps it's another growth stage of tyrannosaurus itself it doesn't really look anything like the dromeosaur designs for Walking with Dinosaurs but there are quite a few other therapods known in Hell Creek including some that are only described from teeth so perhaps it was meant to be one of the other random taxa in the formation the head of this therapod does look quite shrink wrapped showing the borders of the skull openings quite clearly but in this particular case it could be be argued this it's the result of some decomposition of the carcass the model is also really quite detailed showing what looked like osteoderms or something running down the top of the snout which although it's speculative and it's still not clear what it's meant to be it is a nice way to show some display structures so that's pretty much every extinct animal that's featured in Death of a dynasty but what about the environments they're shown to be inhabiting the environment represented by the preserved sediments of the hell Creek formation was a large low Coastal flood plain crossed by many Meandering rivers with mountains rising to the West which would eventually become the Rocky Mountains and the retreating Western interior Seaway to the east the climate of this region was warm and humid as indicated by the presence of certain pollens and spores and it seems that large coniferous trees such as redwoods and Pines compris the canopy of forests while sads and other conifers formed a subcanopy beneath which grew an understory of ferns mosses horsetails and Ang sperms the flowering plants these extensive Woodlands were also broken up by open areas of ferns or scrublands and some subtropical swampy areas were also present where palm trees grew this is quite a different picture to that presented in Walking with Dinosaurs then which shows Hell Creek as a volcanic Wasteland with limited islands of greenery in reality it was a lush complex ecosystem with a climate somewhat similar to modern-day Northern Florida the episode does at least mention the abundance of flowering plants which dominates the known diversity of the hell Creek paleo Flora Kenneth also states that the canopy is mostly filled with broad leafed trees instead of conifers however the fossil evidence we have indicates that coniferous plants were still the main components of the canopy while broad leafed trees such as walnut tree and Sycamore relatives were present but made up parts of the secondary canopy although plant macrofossils from Hell Creek are primarily dominated by angiosperms the records from spores and pollen indicate the gymnosperms were still very abundant volcanic ash Fields feature heavily in this episode and there would have been some volcanoes near to the hell Creek region as the mountain building to the West took place several Ash layers are known in the hell Creek formation too and Analysis of the formation where it outcrops in Central North Dakota has shown that there were indeed minerals here likely formed in magmas in the mountain building period to the West so perhaps we can pretend that death of Dynasty is specifically taking place quite close to the regions most affected by the volcanism occurring as the mountains developed still the majority of the hell Creek area would have looked very different to these Ash fields and so it was probably not the best reconstruction of the ecosystem to go with one of the main themes of this episode is built around the idea that nonavian dinosaurs were already on their way to becoming extinct living on a poisoned planet and becoming fewer in number when the asteroid impact occurs and seals their fate well well there's a whole lot we can say about that there has been great debate among scientists as to whether or not non-bird dinosaurs were already in Decline when the impact happened with research done in the '90s just as Walking with Dinosaurs was in production starting to point more towards the hypothesis of a gradual dinosaur decline as well as a decline in other archosaur lineages such as the terrasaurs which we discussed previously work from the ' 80s and early '90s had supported a sudden Extinction but then surveys looking dinosaur diversity across the final stage of the Cretaceous found signs indicating a drop in diversity during the mrican and even a particularly accelerated decline in the latest masteran at least in North America so the recent work done at the time of making Walking with Dinosaurs was seeming to indicate a gradual decline and it therefore makes sense that these ideas were incorporated into the episode however since the late '90s a lot more work has been done on dinosaur diversity Trends with other studies finding that the estimates for diversity had been biased by most of the data only coming from the hell Creek formation and arguing that a relatively small region of Western North America shouldn't be taken to be representative of the conditions across the whole planet taking into account other latest mustc in localities from around the world they found that dinosaur diversity at this time had been severely underestimated other Studies have urged caution when creating dinosaur diversity curves since artifacts caused by biases in the ologic record can very easily obscure the actual evolutionary trends for example variations in how much fossiliferous rocks are actually preserved however these Studies have also taken into account such biases and then still found indications of a gradual decline in therapod and onisan dinosaur diversity for several million years prior to the kpg extinction still more Studies have discovered no evidence for long-term declines in non-avian dinosaurs overall but found that certain groups specifically the ceratopsians and the hydroids in North America did decrease in diversity over the last 15 million years of the Cretaceous then there's another paper utilizing a different kind of statistical analysis to model speciations and extinctions which founds that overall there was a distinct reduction in speciation rate among dinosaurs except in the case of the hydroa forms and the ceratopsians which continued to rapidly speciate through the late Cretaceous so the complete opposite pattern to the other paper then there's even one study from 2004 that found a continuous increase in the diversity of all dinosaur groups over the course of the late Cretaceous another particularly interesting approach was published in 2019 when researchers used ecological niche modeling to show that the apparent decline in North American dinosaur diversity was in fact an artifact and could be explained by a reduction in the available spatial sampling window as a result of the formation of the Proto Rocky Mountains plus sea level drops so they also concludes the diversity has been underestimated as you've probably realized what exactly was happening to the non-bird dinosaurs right at the end is not exactly clear and many very complex systems are involved that make it incredibly difficult to work out the debate continues on even today and you'll see one paper published that supports the decline in diversity and then a few months later there'll be another one using a different approach that supports a sudden disappearance so we can safely say that this is an unresolved issue in paleontology at least for now or at least it's one that paleontologists really like to argue about this brings us to another key area of discussion about the kpg extinction the effect of volcanism versus the asteroid impact towards the end of the Cretaceous Period some intense volcanism was occurring with the eruption of the decen traps in India and at least one of these major pulses in activity potentially occurred right around the kpg boundary some researchers have argued that this volcanism was in fact in fact the main driver for dinosaur extinction and might therefore also explain the drop off in diversity towards the very end of the mrican and then the asteroid impact finished them off this seems to be the hypothesis that death of a dynasty is portraying showing the effects that volcanism is having on the environment and on the dinosaurs of Hell Creek while the asteroid is the final blow however some recent papers have presented evidence supporting the asteroid impact being the main Extinction driver analyzing the timings of the decen trap's volcanism based on global temperature changes recorded by sedimentary rocks they found that the main outgassing events actually occurred before the asteroid hit and that the mass extinction therefore only coincides with the impact this is another case of new papers continually being published and presenting more evidence for either the asteroid impact or the Deen vulcanism being the main Extinction driver although some studies also suggest that a combination of both events is to blame indeed a paper published in 2015 also proposes that the seismic effects from the asteroid impact may have resulted in more massive eruptions of the deck and traps based on their calculations of the timings for both events so again the relative importances to the final Extinction of non-avian dinosaurs and many other groups of organisms of these two catastrophes are unresolved at present the asteroid impact was undoubtedly devastating though triggering a mega tsunami as well as Global wildfires in the first few hours after impact it would have been a very bad time to be alive the ejection of huge amounts of fine silica dust into the atmosphere plus so from the wildfires and carbon dioxide and sulfate Aerosoles from the carbonates and sulfur rocks at the sight of the impact at the Yucatan Peninsula in Mexico then resulted in dramatic global cooling with average surface temperatures dropping by as much as 15° C the presence of these substances in the atmosphere also blocked out sunlight resulting in what has been termed a nuclear winter and modeling of paleoclimates show that photosynthetic activity across the planet shut down within 2 weeks of the impact and stayed like this for almost 2 years ecosystems collapsed and large-bodied animals that weren't adapted to cold dark environments with very scarce food availability underwent severe extinctions and again it was a very bad time for everyone additionally incredible discoveries from a site known as Tannis in North Dakota which appears to preserve deposits dating to the actual day of the impact have been used to show that the Collision occurred during the Northern Hemisphere Springtime looking at paddlefish and sturgeon fossils preserved here that have impact spheral in their Gil rakers they were able to tell that these fish died in Spring which also seems to have influenced the severity of the extinction as spring is a particularly sensitive time in the life cycles of many animals so how is death of a Dynasty's portrayal of this catastrophe well we don't see much of the long-term impact though it is mentioned in the narration but the impact is shown as a massive silent flash which would indeed have been visible from this part of Hell Creek impacting to the southeast of here two flashes would have been visible one as the asteroid compressed the air in front of it as it entered the atmosphere and then the flash of the impact itself then it triggers major seismic activity which again we know occurred due to the sedimentary record showing that a greater than 11 RoR magnitude Mega earthquake was caused by the impact this would have been unimaginably destructive no earthquake on this sort of scale has ever been recorded by humans and it seems that Walking with Dinosaurs actually underplays the devastation only showing it as a slight Tremor that lasts a few moments in reality these earthquakes potentially lasted several minutes and would have been disastrous for the hell Creek forer launching massive dinosaurs into the air and causing death on an unbelievable scale the molten rock falling from the sky did also occur as ejected material from the impact re-entered the atmosphere and rain down across continents this also likely caused the massive forest fires as the atmosphere heated up but this isn't really shown in the episode as we're focused on an ash field with little vegetation however it was then actually a few hours after impact that the sonic boom followed having traveled much slower than the light flashes all the way from the yakatan peninsula and with the boom were the winds racing across Hell Creek at potentially as much as 1,000 kmph so overall the portrayal in this episode does show most of the main stages of the immediate impact effects but sort of condenses the timeline of events down a bit to just a few minutes I realized there were probably a lot of budgetary constraints and it's still a very effective way of showing the impact but it would also have been cool to show what was happening to some of the other animals featured in the episode and perhaps making a bigger deal of the mega earthquakes and overall destruction that occurred death of a dynasty once again has some fantastic music featuring The Return of my favorite piece from the entire series giant of the Skies which plays as the molten rock falls from the sky and absolutely perfectly captures the tragedy of the kpg impact I still think Walking with Dinosaurs has the greatest soundtrack of any documentary Benjamin Bartlett created a true Masterpiece and I still love listening to it all these years later something else I really enjoy with this episode which there's also a bit of in other episodes but it seems like it's more noticeable in this one is the way the episode makes you feel the presence of the camera and like there are actually people filming these Dinosaurs the T-Rex saliva going all over the lens when it Roars is a great detail and there's quite a funny moment when the Tyrannosaurs are fighting and one of them knocks over a tree stump which seems to freak out the cameraman this episode also implies The Narrative structure of following the same individual animals throughout the episode while also featuring the various other organisms in the environment and once again I think it's very effective watching the Tyrannosaurus individuals search for mates reproduce and raise their offspring really makes them feel like real animals and it's also a particularly tragic way to show the end of the age of the dinosaurs with the death of the Tyrant king or queen in this case coinciding with the impact I also like that the episode ends with a final message of Hope though explaining how the birds are a group of dinosaurs themselves and how they've become so successful in the time since the end of the Cretaceous well then that's death of a dynasty reviewed and at last only like 4 years late that's also the entire original Walking with Dinosaurs series reviewed I want to thank everyone for watching this series and being so supportive of these reviews even when they disappeared for a few years and it's been so wonderful to see how many other people love Walking with Dinosaurs as much as I do despite all the inaccuracies that I talk about in these videos I hope I still managed to make it clear that I adore this series and instead of ripping each episode apart I like to think of these videos of more like a celebration of how much paleontology has progressed in the time since Walking with Dinosaurs came out I owe a lot to the series as it had such an influence on me at a very young age and was one of the first paleontology related things I ever watched one of my earliest memories is actually of sitting on the sofa watching the opening to Cru sea with my mom when I must have been about 3 or four and ever since then I've been fascinated by the natural world and its history I hope you've enjoyed all these accuracy review videos and I would love to keep them going and cover all the specials plus walking with beasts Walking With Monsters And even walking with cavemen so do let me know if you'd like to see those in future I'm also planning a special interview and retrospective sort of thing with one of the main scientific advisers for the series so do keep an eye out for that it should be very interesting also quickly before I go thank you to Quinn and Amelia for this customade shirt it's the best that's definitely the main reason I watch it anyway thank you so much for watching this video I really hope you enjoyed it and learned something new if you would like to find out more about our world its history and the wonderful life that surrounds us all please feel free to subscribe to the channel if you think we deserve it and if you would like to see more from us

Channel: Ben G Thomas

Views: 596,397

Keywords: Biology, Science, Paleontology, Palaeontology, Dinosaurs, Animals, Nature, Wildlife, Ben, Thomas, Prehistory, Anatomy, Fossil, Bones, News, 7Daysofscience, Days, of

Id: wAnumP7zeAI

Length: 105min 3sec (6303 seconds)

Published: Sun Feb 04 2024