Planet Dinosaur – A Retrospective Review

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Planet Dinosaur – A Retrospective Review


Image source

What’s that? You thought Walking with Dinosaurs would be the last time the BBC would try its hand at a dinosaur documentary???

You. Thought. WRONG. B*TCH. Cuz Planet Dinosaur is a thing.

Planet Dinosaur is the BBC’s next major dinosaur series after Walking with Dinosaurs. It was, in fact, produced and directed by Nigel Paterson, who also gave us Walking with Beasts. Only this time, they had an additional 12 years of paleontological discoveries, advancements in CGI, and critical reviews of their previous series under their belt. In fact, here’s a fun fact for you: they could now render not just animals, but also entire environments with just CGI, with only a third of the budget of WWD (link). The animals no longer needed to have clay models built before being transferred over to a computer; they could base model, sculpt, and paint all in the computer (link).

It shocks me to say this, but Planet Dinosaur is now a decade old. And now, it’s time to review it, like I have with When Dinosaurs Roamed America, Valley of the T. rex, and Walking with Beasts (yes, I actually reviewed WWB before this, even though PD’s 10th is before WWB’s 20th). Unlike WDRA, not all of the content from this program aired in one day. So I will post reviews for each episode on its respective anniversary. Once I start posting the actual reviews, I will have a directory posted in this OP for quick and easy access to each episode's review (instead of having to scroll down).

Directory:
- Lost World
- Feathered Dragons
- Last Killers
- Fight for Life
- New Giants
- The Great Survivors
- Overall verdict

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Lost World:


Promotional art for Planet Dinosaur. Image source.

• The intro of Planet Dinosaur is relatively subdued compared to some other paleo documentaries. It doesn’t have a super loud, dramatic track like Walking with Beasts, Walking with Monsters, or Dinosaur Revolution. Even the opening of Walking with Dinosaurs comes off as more dramatic with its orchestral theme. But it doesn’t have to be. It’s already satisfying to hear, as dinosaurs you may have never even dreamed of fill the screen.
  
  John Hurt accompanies this by giving us some opening narration that perfectly captures what we’ve come to learn about dinosaurs in relatively recent years. 10 years on and I’ve never forgotten the opening line, “We are living through the golden age of dinosaur discoveries”. And you know what? 10 years on, I think Hurt is still correct.
• To start off with, John Hurt (who I think did a great job narrating) tells us that both Spinosaurus and Carcharodontosaurus were bigger than T. rex. He doesn’t outright mention the two yet, but it’s obvious that these are what he’s talking about. I’m just gonna say this: I think it’s better to just say both are within T. rex’s size range as opposed to flat out claiming that any one of these were bigger. You could debate endlessly on which giyunt therapod (did I ever mention how much it irks me when people misspell “theropod” as “therapod”?) was biggurrr and could kick teh ass of the other, and not really get anywhere until a greater sample size for these species is found. However, what we do have indicates that these species are all in the same size range. Tyrannosaurus, Spinosaurus, Carcharodontosaurus, et al. could all easily weigh as much as a bull African bush elephant. And, with the exception of Spinosaurus, would kick the ass of said elephant ;p.
• One thing I find nice is the use of pictures (sometimes of actual fossils) and visuals and text as basic information. As much as I love a doc or story with solely their depiction of prehistoric life (e.g. WWD or WWB), I wonder if some general public viewers might look at such a doc and say “How do they know that?”. Of course, the purpose of the Walking with series was just to present prehistoric life purely like we would in a nature documentary, and not to explain every extraordinary thing with what the fossil evidence dictates. But for audience members who are not fond of that, Planet Dinosaur might be a more favorable choice.
• It should be noted at this point that this episode’s fauna is a bit of a mishmash. Ouranosaurus is known from the Elrhaz Formation in Niger. This formation is considered to date from the late Aptian (Weishampel et al., 2004) to the Albian (Sereno & ElShafie, 2013), the last two ages of the Early Cretaceous. Spinosaurus is actually known from the Cenomanian to Turonian, the first two ages of the Late Cretaceous. This means that the two did not coexist. Ouranosaurus did, however, coexist with the spinosaurid Suchomimus.
• Also, are we sure that Ouranosaurus’ bill was duck-like? We know that hadrosaur beaks had bone cores that superficially look duck-like, but in life the keratin sheath extended the beak downward (for the upper beak) and upward (for the lower beak). This allowed the beak to crop plant matter. Ouranosaurus was not a hadrosaur, but it was an “iguanodont” (or more accurately, a hadrosauriform), so it wouldn’t surprise me if the same applied to it. At worst, though, I can forgive PD for this.
• Oof, oh uh, so now I gotta talk about Spinosaurus.
  
  I think 17 meters is a bit much, at least for our known specimens. I don’t know a single dinosaur paleontologist or anyone who works with skeletal reconstructions who estimates even the biggest known Spinosaurus at 17 meters in length. At most you’ll get an animal ~15 meters in total length.
  
  Second, needless to say, the model here did not age well. I can’t and don’t blame PD, obviously, since this is a case of Science Marches On. Basically, Spinosaurus would have looked more like this->. Short hindlimbs, and a highly laterally compressed tail with elongated spinous processes.
  
  Third, 11 tonnes. It might have been a reasonable size estimate at the time (from what we inferred of Spinosaurus), but I also think such a mass might be pushing it.
• I will say this, though. Given how obviously non-cursorial the legs of Spinosaurus were, PD was right on the money to not depict it chasing after Ouranosaurus here.
• I really love how the background during these visual explanations is just the habitat itself, with no fauna in sight. Just plants and all that. A little thing, I know, but it’s the little things in life.
• Thanks to this blog post by Tyler Greenfield, I can point out the issues with PD’s model of Onchopristis.
  
  Here, Onchopristis is depicted as basically an upsized modern sawfish. This sort of depiction has become something of a meme, including in paleoart. Onchopristis is actually a member of an extinct suborder called Schlerorhynchoidei, which is actually more closely related to modern skates than to sawfishes. Ergo, the sawfish-like rostrum was actually evolved convergently with pristids; one notable difference was that Onchopristis replaced its denticles throughout its life (so not all would have been the same size at any given moment), while pristids don’t. Also, large spiny denticles have been found from the bodies of close relatives, suggesting Onchopristis would have had them as well. The caudal fin of a private Onchopristis specimen seems to have been reduced or absent (which is similar to modern skates). Lastly, the 8 meter long estimate seems to be exaggerated. 4-5 meters seems more like it
  
  See here for a skeletal reconstruction (with only the skull) of Onchopristis by Tyler Greenfield (to show the relative proportions of the animal). For a life reconstruction, see this piece by Alexander Lovegrove.
• Interestingly, the heron-like wading behavior of Spinosaurus depicted here still seems to be plausible (Hone & Holtz, 2021).
• Another issue with the Spinosaurus here. First, it rakes the Onchopristis with its front claws to kill it, but it does so by slashing from front to back. This requires the hand to be in a pronated position (and that’s exactly what the Spinosaurus does), which is impossible for virtually, if not all theropods. If Spinosaurus is going to slash at the Onchopristis with its claws, it would do so by moving its forelimbs inward, more like a big cat or bear swatting at another animal with its paw.
  
  I also think it would have been better for the Spinosaurus to engage its forelimbs when the Onchopristis was still alive in its mouth, right after it was caught. The muscular, robust-boned forelimbs with huge hooked claws would have helped keep the “sawskate” still and prevented it from struggling too violently.
• I feel like Spinosaurus might avoid eating certain parts of an Onchopristis more because they’re not processable or not nutritious enough, as opposed to it affording to be wasteful.
• First, Rugops was not 8 meters long. Even the most liberal estimates put it at 6 meters long, with one subsequent estimate putting it at as little as 4.4 meters long (Grillo & Delcourt, 2016; based on a skull length of 44.4 cm), although apparently Asier Larramendi and Rubén Molina-Pérez estimated it to be nearly a meter longer than this.
  
  Second, PD writes Rugops off as a mere scavenger on the basis of a weak skull and bite. I think this is based on a media claim from Paul Sereno that Rugops’ skull was not designed for fighting or bone crushing. Thing is, he never goes into any elaboration on how so, nor does he ever discuss this in his original description paper on Rugops. While it is true that Rugops lacked the thickened skull roof of some other abelisaurids, the same could also be said of earlier macropredatory ceratosaurs like Ceratosaurus or Eoabelisaurus (the latter of which seems to now rather be classified as a ceratosaurid; Delcourt, 2018). Yet this doesn’t mean Ceratosaurus had a weak bite, at least as an adult; in fact, there is evidence that points to a powerful bite in this genus (Snively & Russell, 2007; Molnar, 2013). Currently, only part of the cranium is known from Rugops, with no mandible known, so bite force is impossible to test. However, the material we do have suggests a relatively short and deep snout (typical for abelisaurids), and a respectably wide back end of the skull (not tyrannosaur-level wide, but again, respectable). I wouldn’t bet against Rugops being able to bite rather hard. In any case, there’s no way it can live solely as a scavenger (Ruxton & Houston, 2007).
• Interestingly, PD shows us what appears to be direct physical evidence of spinosaurid predation on fish like Onchopristis. Has this ever been published in scientific literature? I’d love to know more about it.
• Then we get to the Carcharodontosaurus. I’m not sure about them starting out their fight with a headbutt and pushing. There are some carcharodontosaurids with what appear to be thickened skull roofs that may have been used for agonistic headbutting (Cau et al., 2013), but Carcharodontosaurus itself does not appear to be one of them (this is how the frontal of Carcharodontosaurus compares to that of Sauroniops pachytholus; image by Andrea Cau). While I certainly don’t think these theropods were adapted for bighorn sheep-style clashing and ramming, I think some (especially those with thickened skull roofs/robust orbital bosses) could have possibly butted heads at closer quarters in a form of lower energy headbutting, similar to elephants. But again, Carcharodontosaurus itself does not even seem to have been one of them.
• Okay, quick note. There comes a point where all you hear is the music playing for the rest of the fight, even though I distinctly remember hearing the actual vocalizations and other sounds of the fight in other videos. Different version, I’m guessing?
• There comes a point where one Carcharodontosaurus literally bites the other’s throat. Pretty sure that would be a death sentence in real life.
• I wish the Carcharodontosaurus, and the theropods in general, had lips in this doc. Oh well.
• Would Ouranosaurus even need to run bipedally for extra speed? This is something I kind of wonder about in ornithopods. Also, the Carcharodontosaurus looks kind of funny as it chases after the Ouranosaurus, taking relatively short strides as it moves. I would realistically expect bigger steps as it moves at max speed. And of course, Ouranosaurus and Carcharodontosaurus did not coexist.
• So, PD gives us a visual of Carcharodontosaurus’ skull, with stress patterns marked by different colors. This is obviously referring to finite element analysis. I don’t know what PD used as a source for the visual here, but the highest stress level they show is yellow. In actual FEA analyses, the highest would be a completely white color, so the skull they show could take some more stress. It is true, though, that carcharodontosaurid crania are not specialized for violently struggling with prey in all directions, especially laterally.
  
  The teeth are indeed laterally compressed, serrated, and not especially made to withstand force equally well in every direction (not like the thick teeth of Tyrannosaurus). However, large theropod teeth are less compressed than the canines of saber-toothed cats and dogs (Halstead, 1991); the former have been known to punch their teeth through each other’s skulls, and the latter are known to struggle with prey much larger than themselves without any problems (and with only their teeth, no less). This means large theropod teeth would be even better suited to withstanding stress from the lateral direction than the canines of saber-toothed cats and dogs (while, of course, still being highly adept slicing tools). Sure enough, we do have evidence of ziphodont-toothed theropods causing remarkable damage to large dinosaur bones. So while PD is overall correct here about the functional morphology of Carcharodontosaurus’ skull, just keep these caveats in mind. Never underestimate the jaws of these giant theropods.
• According to Wikipedia, the small crocs we see here are Elosuchus. But if so, they seem to be too broad-snouted. This is what the skull of Elosuchus looks like.
• Sarcosuchus did not live with Spinosaurus. It would have coexisted with the Ouranosaurus depicted in this episode, but not Spinosaurus. Again, this episode’s fauna is something of a mishmash. In fact, it’s been suggested that the decline of giant crocodylomorphs like Sarcosuchus was associated with the rise of spinosaurids as semi-aquatic apex predators. Whether this is a simple case of ecological replacement or direct out-competition is unknown (Arden et al., 2019).
• Given what we now know of Spinosaurus, I doubt it would be the type to travel long distances on land to search for food. I mean, look at its legs…
• The Spinosaurus lets out a snarl right before it attacks the pterosaurs. Oi.
• Before I talk about the fight, I’m just going to say this about the non-maniraptoran theropod noises in general from this doc. It bothers me how all of them basically sound the same. They’re nice sounds and all, and some of which I can actually envisage a theropod making, but come on. >160 million years of evolution and you expect me to believe all big carnivorous theropods sounded just like each other?
• Okay so, the behemoth battle. One thing I like is the Spinosaurus’ reliance on its claws. When in a confrontation with another large animal (like the similar sized Carcharodontosaurus), the forelimbs aren’t constrained in the same way the snout is. That is to say, while the forelimbs weren’t as relatively long as in big cats or bears, Spinosaurus wouldn’t need to worry about breaking an arm when using them to grip or strike another large animal. It WOULD need to worry about its snout potentially bending or snapping if it struggled too violently with another giant creature. That’s not to say a Spinosaurus might not try to bite (after all, it still had an impaling bite that might still be dangerous if landed on the right body part), but its snout is the more delicate weapon.
  
  On the other hand, at one point the Carcharodontosaurus manages to get itself into a position where it bites the sail of Spinosaurus. One small problem: it’s also in the perfect position to bite the neck. Why doesn’t it just attack there? That would be far more lethal.
• At least John Hurt notes that the balance of power between the two theropods is precarious, implying that these two are more than a match for each other.
• The broken Spinosaurus vertebra shown here has since appeared in a paper authored by Nizar Ibrahim and several others (Ibrahim et al., 2020). But the cause of the breakage does not seem to be discussed here or anywhere else other than Planet Dinosaur. The end credits show that the producers consulted scientists like Nizar Ibrahim and Cristiano Dal Sasso (both of whom published work on Spinosaurus); did one of them make that guess, but never formally communicate the idea outside of that? Right now, I can’t take the claim of this being probable evidence of a run-in at face value.
• The transition to Spinosaurus’ extinction isn’t smooth. It just cuts straight to it. But anyway, turns out the fight was actually a pyrrhic one, as the Spinosaurus dies from its wounds during the drought, foreshadowing its extinction.
  
  (Fun fact: I used to think it was supposed to be a different individual at a point in the future (using a recycled model with recycled wounds) where the species is going extinct.)
  
  The segment appears to hold up, however. The paleoenvironment of the Kem Kem Group indeed shows evidence of being overrun by a marine transgression, resulting in a change from fluvial-deltaic to a coastal, pond, and sabkha (area of coastal flats where flooding occurs every now and then, resulting in clays, evaporites, and salts) (Ibrahim et al., 2020). Spinosaurus could very well have become extinct as a result of the environmental change the region saw.

Final verdict:
No one will ever be able to look at this episode the same way again. Much of that is indeed thanks to the elephant in the room that is Spinosaurus. Of course, this isn’t Planet Dinosaur’s fault, as much of what we now know about Spinosaurus came to light after the fact. But even so, it’s still jarring to see how poorly the anatomy of this Spinosaurus aged. There are, of course, additional errors. The fauna is something of an anachronistic mishmash, and for some time in my youth I thought Spinosaurus and Carcharodontosaurus really did live with Ouranosaurus and Sarcosuchus. And I never bought into scavenger Rugops (although, maybe this Rugops does hunt, just off-screen).

However, that’s not to say everything was wrong. Planet Dinosaur did still capture some interesting nuances into the lifestyles of these dinosaurs that the general public might not have been aware of otherwise. The documentary certainly conveyed the semi-aquatic nature of Spinosaurus well. In fact, like I said above, the heron-like wading behavior it exhibits is at least still plausible, if not more so, at the moment than it being an aquatic pursuit predator (as some subsequent depictions portray it as). It covered the bite of Carcharodontosaurus into adequate detail (I could go into more detail on that, but I’m quite deep down the theropod bite iceberg), theropod air sacs, as well as a possible reason for Spinosaurus’ extinction.

There was some missed potential here. This is the only episode of Planet Dinosaur that focuses on just one ecosystem, and a very weird ecosystem at that. The Kem Kem Group is biased towards large carnivorous dinosaurs and crocodyliforms, and it doesn’t appear to be an artifact of preservation, collecting, or observational bias (Ibrahim et al., 2020). Thus, it would have been cool to see the other large carnivores living in this ecosystem, such as Deltadromeus, a large (currently unnamed) abelisaurid, and maybe Sauroniops (assuming it wasn’t a junior synonym of Carcharodontosaurus like the aforementioned study argued). There was even a large crocodyliform with recurved, laterally compressed teeth, presumably for preying on terrestrial animals. At least some of these were definitely known at the time Planet Dinosaur was being made. In fact, given that Sarcosuchus and Ouranosaurus weren’t members of this fauna, the producers could have cut these out and put some of these other large carnivores in the show instead.

So overall, from the perspective of someone who’s looking to learn about these dinosaurs, this episode has lost some of its luster. In fact, this is probably the episode I urge you the most to not take completely at face value now. But it’s still an entertaining watch, and where it hasn’t become outdated, it can still be somewhat informative. It may also be a useful reference point for someone who’s not looking to learn, but simply to see how people thought these dinosaurs (especially Spinosaurus) were like at the time. And to be fair, that’s probably what we should all be doing at this point.

[creature386]

The waiting time is over. Definitely a nice read while eating.

Anyway, to give my own retrospective review, the Spinosaurus is basically Dal Sasso's 2005 Paper: The Documentary (you know, this one). The length is the middle between the 16-18 m figure given in the paper while the weight is probably the 7-9 t number with some extra tons, as the producers must have realized how unrealistically low it is. Also, IIRC, it was this rostrum that they showed while discussing Spinosaurus ability to detect movement in the water.
I don't think direct physical evidence of Spinosaurus predation on Onchopristis exists, but they might be referring to an association between the two described in the paper.

An isolated fish vertebra associated with the specimen is embedded between the right second premaxillary alveolus and its erupting tooth and can be tentatively referred to ?Onchopristis sp. (Stromer, 1926:taf I, fig. 7), a sawfish that is very abundant in the Kem Kem beds

So, yeah, I think they took pretty heavy inspiration from it.

It's interesting to see how, so far, PD appears like a perfect mirror to DR. The animal behavior is fairly realistic and it's very informative, but the models and the mismatched wildlife are problems.

Also, I don't know why, but I feel like it would have been more fitting to title their second episode Lost World in reference to the second installment of the Jurassic Park franchise. But then again, the title fits the weirdness of this particular ecosystem.

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Sept 14, 2021 20:03:54 GMT 5 creature386 said:

Anyway, to give my own retrospective review, the Spinosaurus is basically Dal Sasso's 2005 Paper: The Documentary (you know, this one). The length is the middle between the 16-18 m figure given in the paper while the weight is probably the 7-9 t number with some extra tons, as the producers must have realized how unrealistically low it is.

I didn't realize how influential that paper must have been when I was writing this. It's scary how accurate your descriptive summary of it is.

Sept 14, 2021 20:03:54 GMT 5 creature386 said:

I don't think direct physical evidence of Spinosaurus predation on Onchopristis exists, but they might be referring to an association between the two described in the paper.

An isolated fish vertebra associated with the specimen is embedded between the right second premaxillary alveolus and its erupting tooth and can be tentatively referred to ?Onchopristis sp. (Stromer, 1926:taf I, fig. 7), a sawfish that is very abundant in the Kem Kem beds

So, yeah, I think they took pretty heavy inspiration from it.

Huh. That's cool, so we really do have some evidence that it was feeding on fish like Onchopristis (and the idea that it came from predation is not at all hard to believe).

Sept 14, 2021 20:03:54 GMT 5 creature386 said:

It's interesting to see how, so far, PD appears like a perfect mirror to DR. The animal behavior is fairly realistic and it's very informative, but the models and the mismatched wildlife are problems.

Rival to DR at the time, right? Very weird...

I think there are at least a few more misplacements later on, though the ones I can think of right now are more minor or ambiguous.

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Feathered Dragons:


Screen capture from Planet Dinosaur. Image source.

• We’re first introduced to Epidexipteryx. The actual age of the Daohugou sediments it was found in is contentious, with ages anywhere from 168-152 million years ago being possible (Zhang et al., 2008). Although, it’s been more than a decade since the original description paper, so I don’t know if there have been any subsequent refined estimates.
• So yeah, the thing about Epidexipteryx here is that it looks hella weird. It’s depicted using its elongated clawed fingers to remove grubs from trees, similar to an aye-aye. This is before the discovery of Yi qi, another scansoriopterygid that was found with wing membranes (previously unknown in dinosaurs). Based on this, it’s likely that Epidexipteryx also had wing membranes between its long fingers, looking closer to this depiction by Emily Willoughby. So not a dinosaurian aye-aye, but a glider with wing membranes. Which is still pretty cool.
  
  It also seems to pronate its hands when trying to dig out grubs, which of course isn’t possible.
• Sinraptor is pronounced as SIN-raptor here. It’s actually SYN-raptor; the Latin prefix is “Sino” (meaning Chinese).
• The Saurornithoides model used here is recycled for other troodontids as well as Bradycneme (I’ll talk more about the latter in a subsequent review). The model and feathering look nice, although it is not fully feathered. I would add feathers on the forelimbs and tail; early troodontids like Jianianhualong seem to support such feathered covering.
• An oviraptorid (looks like they don’t specify what species, though) is seen raiding the nest of the Saurornithoides. It digs with its forelimbs and seems to have to get its palms facing backwards which, again, wasn’t possible.
• TV Tropes should add this Saurornithoides under the “Butt-Monkey” trope. It gets one egg eaten by the oviraptorid before it can scare it off, the oviraptorid steals one more egg before it runs away, and to really cement its status as this, it gets ambushed and killed by a Gigantoraptor.
• Speaking of Gigantoraptor, it looks like it’s out of its time period. Originally, the rock formation it was found in (Iren Dabasu, aka Erlian) was thought to be late Campanian or early Maastrichtian in age. More recently, though, detrital zircon uranium-lead (U-Pb) dating suggests this formation is actually Cenomanian in age (~96 million years ago) (Guo et al., 2018). So it looks like Gigantoraptor’s placement with the Campanian-aged Saurornithoides is the result of outdated info. Like 80% of the stuff I come across in these reviews.
• ”It was…like finding a mouse the size of a cow.” - John Hurt (1940-2017)
  
  Amazing.
• If the statement about Gigantoraptor being the largest feathered animal ever discovered wasn’t inaccurate then, it certainly is outdated now. Yutyrannus was described the year after (although, there are apparently bigger estimates for Gigantoraptor). Sinotyrannus (which lived with Microraptor btw) was known a couple years before and integument from it is currently unknown, but I wouldn’t bet against it having feathers either. Likewise, Deinocheirus, whose remains only became better known three years after this doc, had a pygostyle at the end of its tail, suggesting a fan of feathers at the end of its tail. This is further supported by the fact that ornithomimosaurs are known to have had pennaceous feathers (Lee et al., 2014). Lastly, while we don’t have direct evidence for feathers for Therizinosaurus, people seem more receptive to the possibility of it being feathered these days, since we know other therizinosaurs had feathers. Whether Therizinosaurus also was due to its giant size may be more debatable, but feathers at least seem reasonable.
  
  See, look how much knowledge on feathered dinosaurs changed even within the past decade. Just imagine how amazed the producers would have been by Deinocheirus and Yutyrannus. I somehow doubt John Hurt took it upon himself to learn more about dinosaurs after narrating PD, but I like to think that if he did, we would have been fascinated too.
• Nice Gigantoraptor fight! Kicking, pecking, wing flapping (and battering?), just what I’d expect! And then there’s the bird-like male-female courtship displays that come afterwards.
• The animals you see in this segment (Microraptor, Xianglong, Sinornithosaurus, and Jeholosaurus) are all found in the Jehol Group. However, the Jehol Group is composed of multiple different formations. These particular animals are known from either the Yixian Formation or the Jiufotang Formation. The latter is slightly younger than the youngest bed of the Yixian, and is where Microraptor is found. Therefore, Microraptor seems to be misplaced by a couple million years.
• Microraptor fossils are touted for their excellent state of preservation in this doc. In fact, they are so well preserved that we later discovered its true coloration (in contrast to the one we see here). One specimen was so well preserved that even the melanosomes (pigment cells) of its feathers were fossilized. The structure of these melanosomes was consistent with a black, iridescent coloration (Li et al., 2012). It would have looked something like this).
• Did the Microraptor just make a goose vocalization (19:58 mark)?
• Microraptor is claimed to have been an awkward walker on the ground. This claim seems to be a popular one. But I can’t bring myself to agree with it. Microraptor has cursorial legs (Persons & Currie, 2016). I mean, just look at the damn thing->. I think Duane Nash explained it best on his old Antediluvian Salad blog (link).
  
  “Microraptorines could move and move around well on the ground. Assertions that the feathers on the legs would cause undue hardship and toil are simply not meted out when viewed against the panoply of abuse modern birds put their flight feathers through. I was recently watching the flock of California condors that are maintained at the Santa Barbara Zoological Gardens. Splendid birds and you really get a sense for the nuanced social dynamics at play when you watch them for some amount of time. One of the birds sort of crash landed into the branches of a large oak tree in the enclosure after a small skirmish. Mind you this was a California oak (not sure the species) and it had the harsh, spiky leaves of a oak adapted to the drought prone, semi-arid climate of California quite unlike the soft rounded leaves you might encounter on oak leaves in more verdant climes. Anyways, this was no soft landing that the condor made into the tree and it was totally caught up in the brittle, spiky canopy. The bird (second heaviest flying bird in North America) then proceeded to use its wings (e.g. its flight feathers) to literally "swim fly" through the brambly and spiky oak foliage until it could get up to a solid enough limb to perch upon. I got the feeling this was no extraordinary ordeal for the bird and had probably done it a number of times. Not a flight feather lost or even seemingly damaged. Long story short flight feathers - whether on the arm or leg - are not the wimpy structures sometimes assumed to be and are  deeply anchored within the dermis or even into the bone and can both receive and deliver substantial abuse and punishment. Microraptorine leg feathers were doubtless anchored well into the leg . Furthermore there is no reason that the feathers on the leg would not have been able to fold up against one another as the leg moved or crouched. It is also entirely possible that such feathers could be moved so as not to scrape against the ground. This is no different than what the flight feathers on the arms of birds and maniraptorans presumably are able to do.
  
  Anyone who argues that bird feathers - especially the pennaceous "flight" feathers whether on the legs or arms - are prone to falling off, getting damaged, or just inhibiting to violent, physical interactions just has not been paying attention to what birds actually do.”
• I forgot that PD knows about the color of Sinornithosaurus too until I resumed watching this episode. Nice.
• The doc is right about Sinornithosaurus’ time of activity; it was indeed cathemeral (Schmitz & Motani, 2011). The presence of venom is…highly questionable, unfortunately (interestingly, according to TV Tropes, the companion book knows this). Grooved teeth are present in other theropods, and there is no obvious sign of a venom sac (Gianechini et al., 2011).
  
  I will, however, bring up my own hypothesis for the grooved teeth of Sinornithosaurus. Although the specimen originally looked at by the “venom authors” seems to have had some of its teeth slipped out of their sockets, other specimens indeed seem to have fully articulated teeth that are similar in length to the ones they originally examined (Gong et al., 2010). So Sinornithosaurus does seem to have had long teeth (though maybe a bit less so than Gong et al. originally thought). And the longer the tooth, the more liable it is to snap, all else being equal. So what do you do to keep elongated teeth strong? By having grooves on the side of the teeth, the amount of surface area for enamel is increased. Enamel is the hardest substance on a tooth, so increasing its surface area on a tooth would make the tooth stronger (Folinsbee et al., 2007). So I believe Sinornithosaurus’ tooth grooves served to keep its long teeth strong. Most of Sinornithosaurus’ teeth were also laterally compressed, recurved, and serrated, you know, the usual for theropods. With long, yet strong, blade-like serrated teeth, Sinornithosaurus would have been able to create large, severe wounds on its prey, probably bleeding them out. Sinornithosaurus didn’t need venom, its teeth were deadly enough on their own. Sounds just like a certain extant large predatory lizard that’s often claimed to be venomous (Weinstein & White, 2015; Ducey et al., 2016)…
  
  Although, I’m still crossing my fingers for an actual venomous dinosaur one day.
• ”And Microraptor not only hints at how flight developed, but also that dinosaurs still live amongst us today…as birds.”
  
  *loud applause*

Final verdict:
As John Hurt’s closing narration alludes to, the theme of this episode is feathers, and all the different functions they had in all the strange feathered dinosaurs we’ve discovered. And I’d say PD covered this quite well in this episode. You get oddballs like Epidexipteryx, giant oddballs like Gigantoraptor that act very much like birds, and the Jehol biota, which is rarely ever featured as one united fauna in paleomedia. Of course, some information in this episode doesn’t hold up today (most notably the venomous Sinornithosaurus), but aside from that, the theme of feathers, as well as the blurring line between dinosaur and bird is conveyed very well here. In fact, right at the end John Hurt utterly destroys that line by cementing the fact that birds are dinosaurs.

[creature386]

(Finally have a new computer so that I can comment on this.

I must say, my memories of that segment were a bit rusty, so, I had to read the trope page as I read that review. It's interesting how these "themed episodes" seem to be the norm for PD with the first arc-based episode being more of an outlier.

But it's definitely a beautiful theme for an episode (especially given how it's more specific than something like survival tactics). One does wonder how this episode would have looked after the discoveries of Yi qi, Yutyrannus and the new Deinocheirus material (although Amazing Dinoworld already had that last bit covered). I even wonder if the discovery of Sciurumimus could have motivated them to add a very brief segment in Germany to discuss it (and I wonder what they would have said about its phylogeny; and if they'd have discussed it in much depth at all). Speculation, speculation. I feel like "feather episodes" should be obligatory for multi-episode dinosaur documentaries these days.

P.S. Funnily enough, the Saurornithoides does in fact have a ButtMonkey entry on its character page (though it's possible you added it yourself after composing the review).

[Infinity Blade]

I guess I must have missed that part of the Saurornithoides' TVTropes page. Summarizes it pretty well, though.

I think Yutyrannus would definitely have been featured had they known about it back then. The idea of a "feathered killer dinosaur" is just way too attractive. I'm grateful for what we got, though. I like that Planet Dinosaur put the spotlight on some very strange dinosaurian forms in this episode.

[Infinity Blade]

Last Killers:


Promotional image for Planet Dinosaur. Image source.

• Just gonna start off with saying this: there’s something so satisfying and refreshing for a work of dinosaur media to not feature Tyrannosaurus in the flesh at all. And ngl, this is actually a little bit of what makes Planet Dinosaur, Disney’s Dinosaur, and Dinosaur Planet interesting to me (the last one actually does feature T. rex, but it only has short screen time there). There are literally hundreds, if not thousands of other non-avian dinosaur species to help you showcase the splendor of the dinosaur kingdom. Why not use those?
  
  I don’t say all this because I hate T. rex or anything. In fact, I say this for the exact opposite reason: I’m a fan of Tyrannosaurus rex, and I don’t like the fact that it’s basically now just bread and butter among the dinosaurs. When you actually take a look at it, and see what about it sticks out from other dinosaurs, it is anything but.
  
  That said, Tyrannosaurus is mentioned here and there throughout this entire program. In fact, as TV Tropes points out, it’s basically used as a measuring stick for how tough a dinosaur is here (especially the three biggest theropods in this series), which goes to show you how much of a reputation it has.
• The skeletal PD shows for Gorgosaurus seems to be based on a juvenile specimen, looking something like this skeletal by Scott Hartman. I think for some time it was common to have some juvenile Gorgosaurus to represent its anatomy and size. A real adult Gorgosaurus, however, would look much more impressive (this reconstruction is by randomdinos).
• I feel like the Daspletosaurus isn’t as heavily built as it should be. This is a large tyrannosaurid we’re talking about, after all, and they’re known for their massive barrel chests.
• At times John Hurt seems to pronounce Daspletosaurus’ name as “des-PLAT-o-sore-us”, although up to the point I’m at now, I think he does pronounce it once more like “das-PLET-o-sore-us”, which is closer to the mark (I personally pronounce it as “das-PLEET-o-sore-us”; I think the difference is due to accent differences).
• Chasmosaurus does indeed have horns, but honestly, they’re not anything special in terms of size compared to something like Styracosaurus or Triceratops (although, the C. “kaiseni” specimen boasts rather impressive orbital horns). I’d say that, at least for short-horned individuals, this genus probably relied more on its beak than its horns for defense (although, there are rib fractures in Chasmosaurus (Farke et al., 2009), which seem more likely to be the result of head blows rather than beak bites to me). Ceratopsids had powerful jaw muscles, and their beaks were sharp-edged and narrow, with both the upper and lower having hooked tips. This means a lot of force was exerted onto a relatively small, narrow area (meaning more pressure) and two sharp beak tips that opposed each other. The result would be a very damaging bite.
  
  Ceratopsids are often said to be reminiscent of rhinos, and interestingly, three out of the five extant rhino species don’t use their horns as weapons (or if they do, very rarely, and not to injurious effect). Instead they use their sharp lower incisors to create deep lacerations that can turn out to be fatal. So I could imagine a Chasmosaurus (or any other ceratopsid), with a body plan rather similar to that of a rhino, being able to use its mouth as a weapon. Only it would be using a sharp beak instead of sharp teeth.
• We now know the tyrannosaurid body plan was actually laid out even further back than Daspletosaurus. Lythronax (which was described two years after PD) was one of, if not the oldest tyrannosaurid known, and it lived as far back as ~80 million years ago. Bistahieversor is roughly as old as Daspletosaurus, but it appears that it was not a tyrannosaurid proper (Voris et al., 2020). The fact that non-tyrannosaurid tyrannosauroids had more or less the same body plan as true tyrannosaurids suggests, then, that this body plan evolved even before tyrannosaurids proper evolved.
• I think the jaw muscle reconstruction shown is based on some older reconstructions where the entire antorbital fenestra is filled with muscle. To my understanding, there was indeed a jaw muscle (M. pterygoideus anterior) that attached to a point in the antorbital fenestra and it would have indeed contributed to closing the jaw. But the antorbital fenestra was largely filled in by air sinuses, so that muscle was certainly not the only thing filling the hole up.
• Yup, they certainly get tyrannosaurid tooth shape right.
• I’m probably going to turn some heads by saying this, but I actually disagree with the “all about the bite” statement. Don’t get me wrong, tyrannosaurids (and abelisaurids) were certainly chiefly about the bite. But there is evidence for non-avian theropods using their feet as predatory tools & weapons, tyrannosaurids included (e.g. McCrea et al., 2015) (I cited this same paper to point out the same thing in my Valley of the T. rex review).
  
  "Out of the 14 tyrannosaurid footprints reported to date, four of which are from Alberta (McCrea et al., 2005. Fanti et al., 2013, McCrea et al., 2014b), eight from British Columbia (Farlow et al., 2009, McCrea et al., 2014b), one from the United States (Lockley and Hunt, 1994), and one from Mongolia (Currie et al., 2003), three footprints from two individuals exhibit remarkable pathologies. This amounts to 21% of individual tyrannosaur footprints with pathologies so far, or 14% of individual trackmakers.
  
  Pedal pathologies, and pathologic tracks, in theropods are not common. A theropod track either isolated or in a trackway, exhibits a characteristic preservation: the medial edge of the foot (digit II) impresses deeper than the lateral edge (digit IV). Digit II is inferred to have relatively more of the animal’s body weight supported on it than digit IV, with digits II and III being the primary weight-bearing digits (Hopson, 2001). Likewise, Lockley (2000, 2007) noted that digit II is typically, shorter, wider and more anteriorly located than digit IV. During the avian step cycle, the subphalangeal pads of all digits contact the substrate simultaneously (Senter, 2009). Assuming the theropod foot moved in a similar manner to that of an extant bird foot (although Farlow et al., 2000 show differences in theropod and avian gait), it is unlikely that the injuries to the digits are the result of normal locomotion. In other words, theropods likely did not contact the ground preferentially with one digit, which might have increased the likelihood of differential stress or injury. It is unlikely that these pathologies were caused by scavenging. It is reasonable to suppose that wounds like this would be caused by restraining large, struggling prey, or fighting with other predators (Tanke and Currie, 2000).”
  
  So while the mouth was certainly the primary weapon, it wasn’t the only weapon.
• The arms race shown here between ceratopsians and tyrannosaurs is kind of wonky, since some of the genera presented didn’t even live with each other. “Raptorex” was originally thought to be from the Early Cretaceous (it’s actually much younger than that, never met Psittacosaurus, and is probably just a juvenile Tarbosaurus), so I can forgive this (you could replace it with Dilong as well). But neither Alectrosaurus and Protoceratops actually lived with each other, and neither lived 85 million years ago.
  
  The idea of an arms race between ceratopsians and tyrannosaurs certainly hasn’t escaped other people, though (just to give you a few examples, here’s one image showing contemporaneous tyrannosauroids and ceratopsians through time, and these ones by Julio Lacerda).
• Most ceratopsid frills were indeed thin and had large fenestrae, and thus probably better suited for show (although, those with horns or spikes projecting outward would have been dangerous as well). There is, however, apparently a Torosaurus specimen with what appear to be healed bite marks on its frill, and Torosaurus’ frill was not thick, solid bone like that of Triceratops (link). So maybe it had at least a bit of a function for protection???
• The Daspletosaurus is young, but the models for adults and juveniles are the same. Depending on just how old this young Daspletosaurus is, I feel like it might be able to pass off as an immature individual, but I’m not sure.
• ”Even two Daspletosaurus pose little threat”. I think we’re pushing it here, unless both are immature.
• I’m assuming that the troodontid and Edmontosaurus segment here is based on the Prince Creek Formation. The troodontids there were indeed significantly bigger than the ones down south in Alberta and Montana. But given that we now know that Nanuqsaurus was inhabiting the region (Fiorillo & Tykoski, 2014), I think it’s safe to say that tyrannosaurids were indeed apex predators in Alaska too. They were smaller than most other tyrannosaurids, but still a lot larger and more formidable than even these extra large troodontids.
• The Edmontosaurus forefeet would be reconstructed differently now, but again, I absolutely cannot fault PD for that here.
• Oh, btw, the Edmontosaurus make the same boar(?) noises that the Chasmosaurus makes. For some reason it only just now hit me that in addition to the large theropods making the same noises, this big ornithopod and ceratopsian do too…
• These Edmontosaurus aren’t pushovers, though, so I guess that’s a plus. An adult literally headbutts a troodontid as they maul a juvenile, and the theropods are forced to give up the hunt…
• …until the morning, that is. The juvenile Edmontosaurus turns up dead and the troodontids get to feast. I guess the producers of PD took a tip from the last episode of WWD.
• Ugh, I can’t get past how slow the dinosaurs look when chasing each other! They’re moving quickly (at least the Chasmosaurus and juvenile Daspletosaurus are), but their movements sometimes look too slow for such a speed. The adult Daspletosaurus aren’t even running at all!
• Interesting that John Hurt tells us that this is a mob attack and isn’t carefully planned. Pack hunting in theropods is still a rather controversial issue, and those who don’t agree with coordinated pack hunting still seem to think that attacking in uncoordinated mobs is plausible. So PD sort of hits a middle ground that I believe most people would have no real problem with.
• Tyrannosaur intraspecific aggression is gone over quite well.
• John Hurt then transitions to his talk about abelisaurids by saying “Tyrannosaurs’ domination of the globe might have been total had it not been for a strange quirk in the arrangement of the continents”. If the K-Pg extinction never happened, I legitimately wonder how an alternate timeline biotic interchange between North and South America would have gone. Would tyrannosaurids have competed with native abelisaurids (and baurusuchids)? Or would at least one family have gone locally extinct before that could even happen (like what happened in real life, lol)?
• I love how PD builds up an apparent larger predator living with Majungasaurus, even if the truth isn’t quite that.
• The Rahonavis reuse the same model of the Sinornithosaurus. I’m not sure how to feel about that.
• The bite and grip killing repertoire of Majungasaurus sounds about right. Scott Sampson and Lawrence Witmer’s words on the matter sum it up: “Majungasaurus is here postulated to have been able to dispatch large prey more rapidly than other basal theropods, employing a combination of relatively few, prolonged, penetrating bites and powerful neck retraction to produce massive wounds, which is in accord with the biomechanical findings of Therrien et al, (2005)” (Sampson & Witmer, 2007). Additionally though, a subsequent discovery found that Majungasaurus had a very high tooth replacement rate compared to other carnivorous dinosaurs. Bite marks on other Majungasaurus and herbivorous dinosaur bones demonstrate it was gnawing on or even eating bone, but abelisaurids did not have the same war hammer spikes for teeth that tyrannosaurids had. To make up for this, they would simply replace broken teeth at a very high rate (D'Emic et al., 2019). In this respect, they’re even more like southern tyrannosaurid counterparts.
• A mother Majungasaurus mortally wounds an adult male by biting its neck and eats it. Hmmm, where have I seen this before?
• We get a brief cameo of Deinosuchus. One Centrosaurus is grabbed by one and dragged underwater. Sadly, this was all the time they could squeeze in for the other apex predator of Campanian North America.
• For my penultimate point, I’m going to briefly go back on a previous point. Given that we now know that tyrannosaurids were apex predators up in Alaska too, this probably means that, if Planet Dinosaur were made today, we’d have no third family of “last killer dinosaurs” to show in this episode…right? Wrong.
  
  You see, while Planet Dinosaur showed us a clear dichotomy between northern tyrannosaurs and southern abelisaurs (actually, abelisaurs were in Europe at this time), the situation is actually a bit more complicated than that. While tyrannosaurids dominated Laramidia (the western half of North America at the time), a different family of theropods were the apex predators of Appalachia (the eastern half): I am, of course, talking about the dryptosaurids. Dryptosaurids were large tyrannosauroids that lived in eastern North America as late as the Maastrichtian (and presumably, until the very end thereof). While their teeth were pretty much the same as in most other theropods (although, the skull looks more tyrannosaurid-like->, naturally), they, unlike tyrannosaurids, retained well-developed forelimbs with huge, curved claws as adults (this is where the type species gets its species name; aquil-unguis=“eagle claw”). Accordingly, both jaws and claws were important weapons during predation. Since dryptosaurids (and all other eastern North American dinosaurs for that matter) get pretty much no press from popular paleomedia (undoubtedly because the eastern United States is nowhere near as well studied in terms of its paleofauna as the west), such an appearance would have been well-deserved.
  
  And there was yet another group of wicked-clawed theropods terrorizing other dinosaurs in the Campanian to Maastrichtian: megaraptorans. To be fair, a lot of the stuff we now have from megaraptorans came after Planet dinosaur aired, so any attempt at depicting them at the time would have certainly become outdated. But what was known, even back then, is that they sported enormous raptorial claws at the ends of their fingers, just like the dryptosaurids. Perhaps featuring them would not have worked or aged as well as depicting dryptosaurids, but still doable in my opinion. And as with dryptosaurids, it would have given them deserved pop culture coverage.
  
  So while there were no top predator troodontids in the last ten or so million years of the Mesozoic, you did have two groups of predatory dinosaurs with wicked claws on their fingers in different parts of the world. Oddly enough, in stark contrast to the brawny-skulled and puny-armed tyrannosaurids and abelisaurids.
• ”…they [tyrannosaurids and abelisaurids] were the last of the killer dinosaurs.”
  
  Predatory Cenozoic birds: So you’re just gonna ignore us and treat us like jokes despite our 66 million year history?!?!
  
  Tyrannosaurids and abelisaurids (towering over them): Yes.

Final verdict:
What can I say? It’s a solid introduction to tyrannosaurids and abelisaurids (and to a lesser extent, troodontids). “Last Killers” certainly conveys its theme well, with tyrannosaurids, abelisaurids, and Alaskan troodontids presented as being clearly different from the predatory theropod norm. The mistakes and potential issues are definitely present, but they seem relatively minor, with arguably the biggest one being a case of Science Marches On; troodontids would not have been the apex predators of Prince Creek. There are other aspects of tyrannosaurid and abelisaurid biology that accentuate their uniqueness among predatory dinosaurs (like their postcranial anatomy), which PD sadly doesn’t cover here. Then again, you might be able to chalk that up to time constraints.

[creature386]

Sept 28, 2021 19:14:13 GMT 5 Infinity Blade said:

Just gonna start off with saying this: there’s something so satisfying and refreshing for a work of dinosaur media to not feature Tyrannosaurus in the flesh at all. And ngl, this is actually a little bit of what makes Planet Dinosaur, Disney’s Dinosaur, and Dinosaur Planet interesting to me (the last one actually does feature T. rex, but it only has short screen time there). There are literally hundreds, if not thousands of other non-avian dinosaur species to help you showcase the splendor of the dinosaur kingdom. Why not use those?

I don’t say all this because I hate T. rex or anything. In fact, I say this for the exact opposite reason: I’m a fan of Tyrannosaurus rex, and I don’t like the fact that it’s basically now just bread and butter among the dinosaurs. When you actually take a look at it, and see what about it sticks out from other dinosaurs, it is anything but.

That said, Tyrannosaurus is mentioned here and there throughout this entire program. In fact, as TV Tropes points out, it’s basically used as a measuring stick for how tough a dinosaur is here (especially the three biggest theropods in this series), which goes to show you how much of a reputation it has.

Yeah, PD deserves kudos for that. The absence of T. rex might be why its featured roster of giant prehistoric killers is so large. From Spinosaurs, to Carcharodontosaurus, to Allosaurus/Saurophaganax, to Mapusaurus, to the ones shown here, they were really rigorous with covering all the "giant theropod" bases. To an extent, any sufficiently big killer theropod can evoke a similar effect as T. rex (especially if the comparison is drawn), but the effect is somewhat diminished. They knew how to make up for that.

Sept 28, 2021 19:14:13 GMT 5 Infinity Blade said:

• The skeletal PD shows for Gorgosaurus seems to be based on a juvenile specimen, looking something like this skeletal by Scott Hartman. I think for some time it was common to have some juvenile Gorgosaurus to represent its anatomy and size. A real adult Gorgosaurus, however, would look much more impressive (this reconstruction is by randomdinos).

Interesting. I always thought of Gorgosaurus being the more slender of the two and being specialized in more "fleet-footed" prey (e.g. hadrosaurs) than Daspletosaurus (though, as the Wiki discussion shows, this is rather contentious). Then again though, Daspletosaurus was similalry bulkier than what they showed us.

Sept 28, 2021 19:14:13 GMT 5 Infinity Blade said:

Ceratopsids are often said to be reminiscent of rhinos, and interestingly, three out of the five extant rhino species don’t use their horns as weapons (or if they do, very rarely, and not to injurious effect). Instead they use their sharp lower incisors to create deep lacerations that can turn out to be fatal. So I could imagine a Chasmosaurus (or any other ceratopsid), with a body plan rather similar to that of a rhino, being able to use its mouth as a weapon. Only it would be using a sharp beak instead of sharp teeth.

Gotta admit, I wasn't aware of that particular rhino/ceratopsian similarity.

Sept 28, 2021 19:14:13 GMT 5 Infinity Blade said:

The arms race shown here between ceratopsians and tyrannosaurs is kind of wonky, since some of the genera presented didn’t even live with each other. “Raptorex” was originally thought to be from the Early Cretaceous (it’s actually much younger than that, never met Psittacosaurus, and is probably just a juvenile Tarbosaurus), so I can forgive this (you could replace it with Dilong as well). But neither Alectrosaurus and Protoceratops actually lived with each other, and neither lived 85 million years ago.

Yeah, I found their "arms race presentation" really cool when they first showed it due to how iconic the T. rex/Triceratops jingoism is. However, it's really silly when you consider that armsraces accelerate evolution into hyperdrive. No way that ceratopsian/tyrannosauroid armsrace got sustained for as long as shown there, especially when, for most of their history, they had bigger enemies to worry about than each other.

Sept 28, 2021 19:14:13 GMT 5 Infinity Blade said:

• These Edmontosaurus aren’t pushovers, though, so I guess that’s a plus. An adult literally headbutts a troodontid as they maul a juvenile, and the theropods are forced to give up the hunt…
• …until the morning, that is. The juvenile Edmontosaurus turns up dead and the troodontids get to feast. I guess the producers of PD took a tip from the last episode of WWD.

Considering the status of ornithopods as the redshirts of dinosaur media, that's still quite the accomplishment.

Sept 28, 2021 19:14:13 GMT 5 Infinity Blade said:

• Ugh, I can’t get past how slow the dinosaurs look when chasing each other! They’re moving quickly (at least the Chasmosaurus and juvenile Daspletosaurus are), but their movements sometimes look too slow for such a speed. The adult Daspletosaurus aren’t even running at all!

I just watched that segment again and I found it funny how they often refused to show the Chasmosaurus feet when it was supposed to be running fast. Animation must be hard (though I'm not an animation expert so I can't tell if that was the issue).

Sept 28, 2021 19:14:13 GMT 5 Infinity Blade said:

• Interesting that John Hurt tells us that this is a mob attack and isn’t carefully planned. Pack hunting in theropods is still a rather controversial issue, and those who don’t agree with coordinated pack hunting still seem to think that attacking in uncoordinated mobs is plausible. So PD sort of hits a middle ground that I believe most people would have no real problem with.

The whole "juveniles chase; adults provide the muscle" feels pretty coordinated, but then again, there are probably different levels of coordination (plus, I think Hurt mentions that this attack appears planned even when it isn't; might just be instinctual).

Sept 28, 2021 19:14:13 GMT 5 Infinity Blade said:

• The Rahonavis reuse the same model of the Sinornithosaurus. I’m not sure how to feel about that.

Too bad Woody Woodpecker wasn't available.

Sept 28, 2021 19:14:13 GMT 5 Infinity Blade said:

• A mother Majungasaurus mortally wounds an adult male by biting its neck and eats it. Hmmm, where have I seen this before?

I do wonder if PD and JFC had a similar idea when discussing the Majungasaurus cannibalism or if this was a deliberate references (since references are normally Dinosaur Revolution's thing).


Anway, I think this was a great episode (and a great review). I even have slightly more accurate memories of it than of episode 2. I think if there's one area where PD really shines, it's in its portrayals of prehistoric killers. As mentioned earlier, it has quite the impressive roster of Tyrannosaurus substitutes and, as TVTropes noticed, the show uses the word "killer" to almost comical degrees (it's even in the title here!). Of course, much like WWD, it does a great job at portraying these animals as animals rather than monsters. At the same time, PD on average does a better job at conveying the awesomess of predatory dinosaurs (and their prey animals for that sake) than DR did, IMO (even if it's probably the cause of a few science goofs, like the exaggerated arms race). Just my 2 cts (I think I'll mostly be covering the entertainment aspects, as you're already covering the science very well).

[Infinity Blade]

Sept 29, 2021 2:50:44 GMT 5 creature386 said:

Interesting. I always thought of Gorgosaurus being the more slender of the two and being specialized in more "fleet-footed" prey (e.g. hadrosaurs) than Daspletosaurus (though, as the Wiki discussion shows, this is rather contentious). Then again though, Daspletosaurus was similalry bulkier than what they showed us.

To an extent I think this may still be true. Gorgosaurus still has the more cursorial legs and albertosaurines had more slender teeth and less robust skulls than similar sized tyrannosaurines (although they bit just as hard and still had very strong skulls and teeth).

[Infinity Blade]

Fight for Life:


Promotional image for Planet Dinosaur. Image source.

• Okay, so at least this episode sticks to one time period just like “Lost World”, although it looks at two separate ecosystems, one terrestrial, one marine.
• No idea how accurately the ammonites are modeled. Sorry, not an invertebrate specialist.
• It’s to my understanding that we now believe that at least some plesiosaurs had small vertical tail flukes. Not anywhere near as big as mosasaur or ichthyosaur tail flukes, of course, but I guess they would have provided an extra bit of thrust.
• So unless you’ve been living under a rock this whole time, Predator X is now known to us as Pliosaurus funkei. The documentary puts its size at >15 meters in length and 45 tonnes. Correct me if I’m wrong, but I believe the early gigantic size estimates were based on its flippers. We later learned that Pliosaurus just had enormous flippers for its size, and modern estimates put it somewhere between 8 and 9 meters in total body length (see this size comparison of some of the largest pliosaur species known).
• Wait, people actually tried calculating the speed of Pliosaurus funkei? 5 m/s? Don’t know how this was calculated or where it was published (if at all), so I’m wary of this estimate. With flippers that enormous, though, it must have had scary fast bursts of speed, acceleration, and maneuverability, even for a plesiosaur (so if anything I advocate for it being even more athletic than claimed here).
• I love the bit where the Pliosaurus surfaces and blows water out of its nostrils. Gives me whale vibes.
• Camptosaurus is depicted here as quadrupedal, with facultative bipedalism. Nowadays, it looks like full-on bipedalism is more likely (this is a skeletal by Scott Hartman).
• In one shot it looks like the forefeet of Stegosaurus look too elephantine, with at least four (if not five) large, blunt nails visible (screenshot).
• It looks like the Camptosaurus and Stegosaurus push each other out of the way for food. Nice little reminder that just because the two species have a symbiotic relationship where they protect each other from predators doesn’t mean they won’t be “selfish” and take food for themselves when they feel like it.
• I’m also skeptical that the kind of chewing the Camptosaurus are seen doing is accurate, but I can kinda let it slide.
• A pterosaur is seen taking off and flying overhead. Apparently this is Kepodactylus, and it looks similar to the models used for some of the other pterosaurs in this series. Here's what it likely would have looked like in real life.
• I know it’s not completely identical, but the coloration of the Allosaurus in this documentary kind of reminds me of the Allosaurus from WWD. Both have red horns (though the PD Allosaurus has a red face in general) and a grayish and blackish or dark greenish body. Makes you wonder if BBC borrowed a bit from its earlier work.
• ”…the most well protected giant of the Jurassic.”
  
  Giant sauropods: Are you sure about that?
• That young Stegosaurus was extremely, extremely lucky. At one point the Allosaurus grabs it by the neck. Allosaurus maw vs elongated, slender neck is extremely one-sided.
• For anyone who might be wondering, the Stegosaurus plate (it’s actually a neck plate) shown here is not thought to have been the result of scavenging after the stegosaur died. That’s because 1) the plates of stegosaurs were bone and are now believed to have been covered in keratin (Christiansen & Tschopp, 2010, contra. Carpenter et al., 2005), and would thus have little nutritive value, & 2) a dead stegosaur would presumably be lying on its side, with its plates drooping downward, making it hard to access by a scavenger (Carpenter et al., 2005). There’s no mention of any evidence of healing on this wound, indicating that the stegosaur didn’t survive the encounter and was killed as the Allosaurus targeted its neck.
  
  Couple that with the evidence of Stegosaurus using its tail as a weapon against Allosaurus (sometimes to lethal effect; link), and you can clearly see how dangerous both were to each other.
• I forgot that PD claims that Allosaurus had a weaker bite than a lion. I remember when I fully bought into that claim. Now I can barely stand to hear it.
  
  The claim that Allosaurus had a weaker bite than a lion is, of course, completely illogical. Allosaurus has a much bigger skull than a lion as a much bigger predator. While obviously not all predators have jaws that are equally powerful relative to size, Allosaurus’ bite wasn’t so weak that it would be out-bitten by some carnivoran a fraction of its size. The only reason this claim was ever made in peer-reviewed literature is because initial bite force estimates for Allosaurus were made using a method that clearly underestimated raw bite force. Later methods (namely multi body dynamics) got much higher bite force figures (Bates & Falkingham, 2012).
  
  How does Allosaurus actually compare to a lion? The supplementary material of Sakamoto et al. (2019) (particularly the second document) has bite force and body mass data on a variety of species, and it just so happens to have made its own estimates for both the modern lion and Allosaurus. Taking the study’s own estimates for these two species, we can see that an Allosaurus that weighs 1,092 kg has a maximum bite force three times greater than a 166 kg lion’s. Now, when you scale this lion up to the size of the Allosaurus, the lion indeed bites harder, but the difference is relatively modest (~16% difference). Of course, there’s more to it than just jaw muscles, as I’ll explain in a minute.
• The Allosaurus headbutts the Camptosaurus…weird.
• The “hatchet-bite” (as I remember calling it back in my early Carnivora forum days) is depicted as the killing method of Allosaurus, where it opens its mouth wide and slams the upper teeth onto its prey like an axe. It is an attractive idea, but there’s a more plausible, sensible interpretation of Allosaurus’ strong skull and neck muscles. Rather than using the cranium like an axe, Allosaurus probably just bit its prey, then relied primarily on its powerful neck muscles to tear off a huge chunk of flesh in a downward motion (Antón et al., 2003). Allosaurus’ neck muscles were well suited to powerful ventroflexion, or in other words, depressing the head downward (Snively & Russell, 2007). Imagine a backhoe, but instead it’s got a lower jaw to bite with, and tears off a chunk of flesh instead of dirt. This is why Allosaurus doesn’t need the super strong jaw muscles of a tyrannosaurid: the neck muscles provided the primary muscle power to cause damage and rip open massive wounds with the slicing dentition. It’s the head-depressing neck muscles that, in effect, increase its bite force; the jaw muscles by themselves are just one relatively small part of the whole picture. We see the same adaptations in predators like saber-toothed cats and terror birds.
• I just realized that the Saurophaganax just kind of comes out of nowhere. Towards the beginning, Allosaurus is built up as this big predator, the likes of which had never been seen before. That’s all kind of squandered by the appearance of the Saurophaganax (which may or may not just be a species of Allosaurus itself). It also makes some stock monster noises that at least somewhat distinguish its vox compared to the other giant theropods.
  
  Nevertheless, Saurophaganax should not be living with smaller Allosaurus. Saurophaganax is known from later strata in the Morrison Formation. In fact, there was a notable trend where allosaurids (and ceratosaurids) increased in size as time passed in the Morrison. This went hand-in-hand with an increase in size of the local sauropods. This means that as the Morrison’s sauropods grew larger, so did the large predatory theropods. It’s evidence that the giant allosaurs were indeed preying upon the big sauropods (Hallett & Wedel, 2016).
• The Pliosaurus almost looks like it rams the Kimmerosaurus. It’s hard to tell, but John Hurt then mentions that the Kimmerosaurus is injured and stunned, so maybe. If so, that’s a pretty neat depiction.
• Kimmerosaurus is also said to have a vicious bite to defend itself with. On the one hand, I’m all for showing that some plesiosaurs were not mere fodder. I believe some of them indeed had vicious bites for predators to look out for. On the other hand, I’m kind of doubtful that Kimmerosaurus is the best example. If Kimmerosaurus’ skull was similar to that of Cryptoclidus (and both are part of the same family), it would have been lightly built and poorly suited for withstanding strain (link). On the other hand, the description of its teeth (strongly recurved, sharply pointed, and laterally compressed; Brown et al., 1986) does make them sound pretty nasty, even if they were intended for small prey. I’m not even sure if the bite of Kimmerosaurus would make for an effective deterrent since, let’s face it, that’s the only way its jaws might be useful for defense against a gigantic pliosaur like this.
• The Pliosaurus’ attack is pretty brutal. Not something that you can’t stomach, but the Kimmerosaurus is literally torn apart.
  
  It’s said that its bite is four times more powerful than that of Tyrannosaurus. While its bite was certainly immensely strong, this is an exaggeration. Another Pliosaurus species, P. kevani, had a skull comparable in size to that of the species depicted here (about 2 meters; Benson et al., 2013), and its bite force was estimated to be up to 48, 278 N (Foffa et al., 2014). To be fair, this is a 3D dry skull estimate, so maybe raw bite force is underestimated to at least some extent. But I don’t think I’d expect it to suddenly bite four times harder than Tyrannosaurus.

Final verdict:
“Fight for Life” focuses on two Late Jurassic apex predators. It’s clear that the “fight for life” isn’t just fought by prey, but by their predators as well. Both Allosaurus and P. funkei fail to capture their prey on at least one occasion, whether due to their prey’s defensive armament or some of their own assets working against them under specific circumstances. Even when they successfully capture their prey, some effort is needed for the hunt to go right. Allosaurus’ speed must overcome the Camptosaurus’ stamina, or it will starve. Pliosaurus must still be wary of Kimmerosaurus’ bite, or it will fail again and starve.

The prey items themselves get some of the spotlight as well. We see a speculative (though potentially plausible) symbiotic association between Camptosaurus and Stegosaurus, and how their different strengths in anti-predator defense help each other. On the other hand, we see Kimmerosaurus hunting behavior, as well as its ability to retreat to shallower waters up against Pliosaurus’ greater power and speed.

PD’s assessments on the two predators’ functional morphology (particularly their jaws) can be alarmingly off at times. The weakness and strength of the jaws of Allosaurus and Pliosaurus (respectively) are grossly exaggerated (although, the producers seem to have gone by information they had available at the time), but what this means for how they are presented differs. In the end, Pliosaurus is still presented hunting and killing its prey in a plausible manner; you can effectively ignore the tidbit afterwards where Hurt says it bites 4x harder than T. rex. Whatever the case, it was undoubtedly more than powerful enough to do what it did in this doc. The same can’t quite be said for Allosaurus, especially how it goes about killing its prey. The hatchet-bite isn’t necessary to explain Allosaurus’ peculiar adaptations, and it wasn’t even back in 2011. So you get a bit of a misleading portrayal of Allosaurus’ killing technique. Also, like I said above, the Allosaurus is kind of undermined here by the out-of-the-blue appearance of Saurophaganax (the likes of which came later in the Morrison, anyway).

One thing I will say was particularly useful this episode was the use of direct fossil evidence to show us predator-prey relationships. Fossils of marine reptiles mutilated by giant pliosaurs and direct evidence of Allosaurus-Stegosaurus conflict really help to highlight the narrative of this episode and make it more believable to the audience.

[creature386]

Oct 5, 2021 19:44:03 GMT 5 Infinity Blade said:

• So unless you’ve been living under a rock this whole time, Predator X is now known to us as Pliosaurus funkei. The documentary puts its size at >15 meters in length and 45 tonnes. Correct me if I’m wrong, but I believe the early gigantic size estimates were based on its flippers. We later learned that Pliosaurus just had enormous flippers for its size, and modern estimates put it somewhere between 8 and 9 meters in total body length (see this size comparison of some of the largest pliosaur species known).

Hey, at least it's not as extreme as with the 25 m Liopleurodon, isn't it?

My memories of 2011 are a bit rusty, but I think 15 was considered exaggerated even then. Knutsen and Duckmiller downsized it to 12-13 m, but that was one year after PD.

This article was from 2011 and it considered the 15 m figure to be upper-end at best:

plesiosauria.com/mines-bigger-than-yours-the-monster-of-aramberri-predator-x-and-other-monster-pliosaurs-in-the-media/

So, PD's figure might have been within the bounds of the scientifically acceptable back then, but only barely so.

Oct 5, 2021 19:44:03 GMT 5 Infinity Blade said:

• Wait, people actually tried calculating the speed of Pliosaurus funkei? 5 m/s?

Yeah, they're usually good at giving citations, but here, I'd have loved to know more.

Oct 5, 2021 19:44:03 GMT 5 Infinity Blade said:

• I forgot that PD claims that Allosaurus had a weaker bite than a lion. I remember when I fully bought into that claim. Now I can barely stand to hear it.

Don't even remind me of that. I'm forced to relive memories of T. rex fanboys claiming that Carcharodontosaurus had a weaker bite force than a jaguar and citing PD's claims as validation.

Oct 5, 2021 19:44:03 GMT 5 Infinity Blade said:

• The “hatchet-bite” (as I remember calling it back in my early Carnivora forum days) is depicted as the killing method of Allosaurus, where it opens its mouth wide and slams the upper teeth onto its prey like an axe. It is an attractive idea, but there’s a more plausible, sensible interpretation of Allosaurus’ strong skull and neck muscles. Rather than using the cranium like an axe, Allosaurus probably just bit its prey, then relied primarily on its powerful neck muscles to tear off a huge chunk of flesh in a downward motion (Antón et al., 2003). Allosaurus’ neck muscles were well suited to powerful ventroflexion, or in other words, depressing the head downward (Snively & Russell, 2007). Imagine a backhoe, but instead it’s got a lower jaw to bite with, and tears off a chunk of flesh instead of dirt. This is why Allosaurus doesn’t need the super strong jaw muscles of a tyrannosaurid: the neck muscles provided the primary muscle power to cause damage and rip open massive wounds with the slicing dentition. It’s the head-depressing neck muscles that, in effect, increase its bite force; the jaw muscles by themselves are just one relatively small part of the whole picture. We see the same adaptations in predators like saber-toothed cats and terror birds.

For slightly more pleasant memories, this reminds me of just how often we used to cite evidence also cited in PD (whether consciously or not) in our debates back in 2012 Carnivora. Just goes to show how relevant that documentary used to be for the early 2010's paleocommunity.

[Infinity Blade]

Oct 6, 2021 1:46:51 GMT 5 creature386 said:

Hey, at least it's not as extreme as with the 25 m Liopleurodon, isn't it?

Oh no definitely not lol.

Oct 6, 2021 1:46:51 GMT 5 creature386 said:

My memories of 2011 are a bit rusty, but I think 15 was considered exaggerated even then. Knutsen and Duckmiller downsized it to 12-13 m, but that was one year after PD.
This article was from 2011 and it considered the 15 m figure to be upper-end at best:
plesiosauria.com/mines-bigger-than-yours-the-monster-of-aramberri-predator-x-and-other-monster-pliosaurs-in-the-media/
So, PD's figure might have been within the bounds of the scientifically acceptable back then, but only barely so.

Huh. Tbh, even today my knowledge on plesiosaur body length isn't exactly top notch, so you can imagine what it was like back then.

Oct 6, 2021 1:46:51 GMT 5 creature386 said:

Don't even remind me of that. I'm forced to relive memories of T. rex fanboys claiming that Carcharodontosaurus had a weaker bite force than a jaguar and citing PD's claims as validation.

>bite force of 8 lbs for carch

Oct 6, 2021 1:46:51 GMT 5 creature386 said:

For slightly more pleasant memories, this reminds me of just how often we used to cite evidence also cited in PD (whether consciously or not) in our debates back in 2012 Carnivora. Just goes to show how relevant that documentary used to be for the early 2010's paleocommunity.

I remember using it back when I was in some old debate on white rhino vs Allosaurus. I think I used it as an actual argument for the theropod (particularly that it had more weapons in the form of its jaws, claws, and "axe-bite"), and being so confident that it was one of the best arguments I could bring up. I'm not even cringing at that, but I just can't help but proverbially chuckle.

[Infinity Blade]

New Giants:


Promotional image for Planet Dinosaur. Image source.

• Ngl, I actually forgot just how the beginning of this episode goes. So I can say that when you see this segment for the first time, you might get an impression that the Argentinosaurus hatchling is going to be faced with a couple of opportunistic predators right after birth, only to be saved (intentionally or not) from a marauding Skorpiovenator at the last minute by an adult. You know, as if it were the protagonist of our story.
  
  Nope. The Skorpiovenator is even more brutal than you’d expect. It doesn’t just swallow the hatchling down, it literally slams it onto the ground and instantly kills it, undoubtedly breaking bones.
• Well, the adults do come shortly after. The hind feet look like they could use larger and more curved claws (this is the general pedal claw shape for sauropods, with only one exception I can think of). The stated size (both body length and mass) seems about right. The overall body shape, though, could definitely use some work. Although Argentinosaurus remains largely incomplete to this day, here are some better ideas of what it would have looked like based on relatives (reconstruction 1, reconstruction 2).
• So, this entire segment here lays out the journey a sauropodlet (to borrow a term from WWD) endures throughout its life. They start off very vulnerable, must fend for themselves right after birth, and grow stupidly fast.
• And we get an ominous foot-first introduction to the apex predator of the region.
  
  As for the bigger than T. rex part, I’ll refer you back to what I said towards the beginning of my review for “Lost World”.
• The narrative of this episode becomes clear after this. Giant plant eating dinosaurs have giant predators. Of course, the former are much, much more giant than their predators, but still. The closest modern analogue involves mammal-eating orcas and giant (baleen and sperm) whales.
• Planet Dinosaur is the only dinosaur documentary I know of that actually returns to an ecosystem it explored previously (certainly in separate episodes). As long as it’s not done excessively (and PD doesn’t do that), I think this has some advantages. You can introduce the audience to another creature from that ecosystem that you haven’t shown before, and without having to go into too much detail on what else lives there. By this point, you know what an Ouranosaurus is (even though it shouldn’t be there), you have some understanding of what this habitat has to offer, and now you’re ready for more.
• I somehow doubt the Paralititan is accurately shaped here either. Something about that head…
• A few snappy crocs are enough to put off the Paralititan. I know smaller animals can definitely drive off larger ones through aggression, but can’t the sauropods just, you know, squash the crocs? Kind of like this->?
• Sarcosuchus gets a reintroduction, but with more detail than in “Lost World”. Nowadays we don’t think it was 12 meters and 8 tonnes like the documentary says, closer to 3.5-4.3 tonnes and about 9-9.5 meters long (O'Brien et al., 2019). Still way bigger than any modern crocodilian.
• ”A cold blooded killer”. Literally.
• Oh, and the track that plays is really cool too. It does not give you comfy vibes, it’s the perfect “oh shit” track.
• An explanation on how giant sauropods eat to get big might not seem interesting, but I think it’s important to have, especially for those who are incredulous as to how a land animal can get this big. I’ve seen dinosaur deniers who have used the (obviously erroneous) argument that animals so big would never be able to adequately feed themselves. If this is how bad it can get (and I admit that this is the worst case scenario), I think it’s worth teaching the general public how dinosaurs can be so big.
  
  I’d like to add something else that PD doesn’t mention. Larger animals actually need less amounts of food relative to their size than smaller ones, despite need absolutely more food.
• Another foot-first Mapusaurus intro…
• Mapusaurus can get even bigger than 10 meters and 4 tonnes. It would need all the size it can get if it wants to take on Argentinosaurus.
• It’s established that a group of Mapusaurus is a threat to even an adult Argentinosaurus. I mean, these giant theropods didn’t get so big for shits and giggles.
  
  To be clear, I’m sure that sauropods that have yet to fully grow would still be favored targets (even subadults could be huge, though, that should be kept in mind). The same holds true for modern mammal-eating orcas and giant whales; with the exception of minkes (which are only about as big as orcas and literally only have fleeing as their defense), orcas rarely succeed in killing adult giant whales because the latter are just too damn big (and sometimes combative). Although, at the same time, I do think carcharodontosaurids like Mapusaurus have an advantage over orcas in that their jaws (which are huge for their size and armed with slicing serrated teeth) can more efficiently injure a gigantic animal than the jaws and rams of an orca (which seem to have modestly large heads/jaws for their size, and conical teeth that are suited for gripping, not slicing).
  
  It’s this nuance that I appreciate here, and that I appreciate the doc illustrating. Mapusaurus would definitely prefer immature or ailing individuals. But could a group take on even an adult on occasion if need be? I’m not ready to bet against it…
• One thing I don’t really like, though, is that a Mapusaurus can be seen literally jumping to attack an Argentinosaurus. Yeah, no way any beast as big as an elephant is gonna jump.
• Also don’t think “flesh grazing” (i.e. taking a bite out and eating it while keeping the animal alive), as if Mapusaurus were a cookiecutter shark, is likely.
• And of course, we’re treated to the dangers of screwing around with a 75 tonne colossus (or even worse, a whole herd of them): an Argentinosaurus stomps a Mapusaurus flat with its forefeet. Fittingly, this is easily one of, if not the most brutal kill I have come across in this show.
• We meet Carcharodontosaurus once again. It gets into a tug of war with the Sarcosuchus and wins (given the roughly 2+ tonne size advantage Carcharodontosaurus would have over Sarcosuchus, I’d say it makes sense that the giant allosaur wins out in the struggle), only to retreat when the whole herd of adults comes to the freed youngster’s aid. You can think of this as basically Planet Dinosaur’s attempt at an up-scaled Battle of Kruger, complete with a crocodylomorph, a terrestrial apex predator, and a (very, very, very) large herbivore.
  
  Only one question: how is the Paralititan not dead? Not only was the Carcharodontosaurus biting the neck of the young Paralititan (given the size of the Carch’s jaws compared to the sauropod’s neck, it could have easily beheaded the youngster), but it was also pulling it as a Sarcosuchus was pulling it in the opposite direction. The little sauropod must have had a god looking out for it (that god being the writer).
• As the Argentinosaurus dies and is scavenged, the track that plays is not a feel-good one (at times). All the more so as John Hurt explains that when these giant sauropods went extinct, so too did their giant predators. And that this same coextinction would have happened time and time again across different ecosystems. This capped off by a Mapusaurus taking one last look at the Argentinosaurus carcass, finding nothing, and walking off into the distance, a foreshadowing of its eventual extinction.

Final verdict:
This episode brings out the big guns. Partially literally. Do I think they did a good job of handling it? Yeah, I guess. The sauropods’ appearance was definitely butchered (though it probably didn’t help that many of these giant sauropods are so incomplete in the first place). However, the documentary did a good enough job of illustrating the rapid growth and (maybe to a lesser extent) the reproductive strategy of these giant sauropods. How these giants are able to sustain themselves is also summarized well (in fact, this episode was my basis for learning more about this), and in my opinion was an important addition. And then, of course, their relationships with predators. The giant sauropods are portrayed as basically immune to predation…except when they’re not, and that’s when the heavy-duty theropods (Mapusaurus and Carcharodontosaurus, although the former is portrayed as more of a threat to adults) are around. One thing I especially liked was the relative risk levels depicted for subadult and adult sauropods of a certain size. So there is some nuance to their depiction of giant theropod predation on giant sauropods. Obviously, the adults are at relatively low risk due to their sheer size. At the same time, a gang of Mapusaurus is acknowledged as a force to be reckoned with by any animal. Lastly, the narrative of the coevolution (and coextinction) of giant sauropods and giant theropods is a straightforward, yet intriguing one. It really puts the “giants” in “New Giants”.

[creature386]

Oct 12, 2021 9:46:20 GMT 5 Infinity Blade said:

Nope. The Skorpiovenator is even more brutal than you’d expect. It doesn’t just swallow the hatchling down, it literally slams it onto the ground and instantly kills it, undoubtedly breaking bones.

Very fitting, given how grim the documentary is overall and this episode in particular (the Mapusaurus kill you discuss later illustrates this quite well). This general grimness, along with the high attention to scientific detail, seems to be a PD hallmark.

Oct 12, 2021 9:46:20 GMT 5 Infinity Blade said:

As for the bigger than T. rex part, I’ll refer you back to what I said towards the beginning of my review for “Lost World”.

Don't they later claim it was 10 m long? This would put their length at merely 8 DUMBs (sorry had to recycle a 2 year old joke here). A T. rex can get up to 9-10 DUMBs long, so, this does not quite match up.

Oct 12, 2021 9:46:20 GMT 5 Infinity Blade said:

An explanation on how giant sauropods eat to get big might not seem interesting, but I think it’s important to have, especially for those who are incredulous as to how a land animal can get this big. I’ve seen dinosaur deniers who have used the (obviously erroneous) argument that animals so big would never be able to adequately feed themselves. If this is how bad it can get (and I admit that this is the worst case scenario), I think it’s worth teaching the general public how dinosaurs can be so big.

While I don't think any dinosaur deniers are gonna watch dinosaur documentaries (otherwise, they won't be deniers anymore), I bet many among the general public are asking themselves such questions. Besides, children love dinosaur media and "how did the dinosaurs grow so big?" is something I'm sure they're asking themselves all the time. So, definitely a useful explanation to have.

Oct 12, 2021 9:46:20 GMT 5 Infinity Blade said:

Also don’t think “flesh grazing” (i.e. taking a bite out and eating it while keeping the animal alive), as if Mapusaurus were a cookiecutter shark, is likely.

Yeah, much like with the hatchet bite, I think that's something a lot of us used to believe back then.

Oct 12, 2021 9:46:20 GMT 5 Infinity Blade said:

Only one question: how is the Paralititan not dead? Not only was the Carcharodontosaurus biting the neck of the young Paralititan (given the size of the Carch’s jaws compared to the sauropod’s neck, it could have easily beheaded the youngster), but it was also pulling it as a Sarcosuchus was pulling it in the opposite direction. The little sauropod must have had a god looking out for it (that god being the writer).

And I complained about the baby Dinheirosaurus from Dinosuar Revolution's Battle of Kruger analog having too much plot armor...

At least Woodstock's baby was "only" implausibly good at keeping the Torvosaurus from biting it. (Wonder how the two baby sauropods would have fared had they switched places.)