|
Post by Shri devi on Jun 5, 2024 2:54:54 GMT 5
Also helps that cat hindfeet are most definitely not as suited for gripping as their forefeet. They have no dewclaw to oppose the other four digits and the claws themselves are less curved and tend to be blunter, despite being protractile (they function more like cleats or dog claws, if you will; they can injure things through sheer force from the hindlimbs). Meanwhile theropods typically had a medially facing hallux that could actually have helped grip things (even if it's not as opposable or nearly as powerful as the hallux of say, a bird of prey). Oh, I was more so talking about leg strength in the context of throwing their weight around and wrestling, but that's also a fair point. A lion that's been pinned down by the raptor will have less defensive options and its kicks would be less effective compared to the Dromaeosaur in the opposite scenario. And again, I think Achillobator has a better chance of pinning the lion than vice versa. As an aside, it also does have some experience with dealing an animal with strong clawed forelimbs and some horrendous clawed feet, Erlikosaurus (and the other Bayn Shire Therizinosaurs): I'm not equating Therizinosaurs to cat, all I'm saying is Achillobator did have to deal with squat, muscular animals armed with knives. Depends on the Dromaeosaur, depends on the bear, but as I said, I would bet on Achillobator against any bear at parity and on Utahraptor against polar bear at parity (though they probably wouldn't be at parity if we're talking male polar bears). A lot of points made in favour of the bears just seem trivial. IB has already addressed the intelligence thing well enough so I won't get into that, but there's points like bears being super strong, can flip a bison, can just wrestle the raptor down with ease or break its skull with one swipe, whatever. To that, see my above points about Achillobator's legs. Then there's forelimb functionality. Sure the bear had more power and mobility with its forelimbs but Dromaeosaurs didn't need that given the mobility and reach of their neck and jaws and besides, they didn't have to unbalance themselves to use their forelimbs. Then there's the issue of bite force/lethality. Well, according to Sakomoto 2020, animals with similar skull widths (not skull length or body size) tend to have roughly similar bite forces, like he found (subadult) Deinonychus, Dromaeosaurus and asian black bears to have had similar bite forces and they had similar skull widths. A 60 cm long Utahraptor skull was approximately 23 cm wide (using the Gaston mount which seems to be the most up to date version and based on the most actual material), which means that its bite force wouldn't be too far off that of a polar bear with a 26 cm wide skull, and given that such a polar bear would most likely outweigh the Utahraptor, that's pretty impressive. Achillobator's skull might've also gotten up to 60 cm (assuming that the maxilla makes up about half the skull length which seems reasonable) so if it had similar proportions then it would have had a similar bite force too. This is not to mention that Dromaeosaurs had long rows of ziphodont teeth that could inflict massive damage in conjunction with their bite force and postcranial musculature (again, legs). Link wasn't loading for me but hmmm...it's not like animals can ever go toe-to-toe with or even prey on/defeat animals that are larger-brained/more "intelligent" than themselves. It's not like nature's filled with stuff like - big cats bringing down similar sized pigs (which are apparently really smart animals) - Komodo dragons doing likewise - rock python killing a spotted hyena - constrictors killing or at least breaking even with big cats - crocodiles killing big cats - great whites killing elephant seals (even bulls) and beaked whales - just sharks generally besting dolphins unless the latter are significantly larger - big cats hunting apes oh...never mind. Oh but I'm sure a bear will Batman up a plan as it's wrestling with a beast rapidly stabbing it multiple times in the gut with knives on its feet, raking with meathooks on its fingers, and furiously shaking off fur and flesh with the serrated steak knives in its mouth...right? Even weaponry aside, I'm like 50% confident something like Achillobator could straight up overpower a same-size bear... though it could probably end things before that with jaws and claws.
|
|
|
Post by razor45dino on Jun 5, 2024 7:31:09 GMT 5
IDK exactly how this site works so i'll just use quotations " I think he is vastly understating the advantages off serrated teeth. In addition, his example of a mammal with a slicing bite was an AWD, an carnivora that has atypical teeth anatomy compared to modern carnivorans. In addition, monitor lizards have much smaller heads than dromeosaurs at parity. AWD kills are often graphic but we don't have accounts of lone AWD's quickly severing the achilles tendons of animal much larger than themselves." I see, agreed with this point. The skulls of dromaeosaurids are very large for their size, and only look slim because they are long, but in reality they were likely about as wide as a similar sized bear or cat. "Corvids are smarter than BOP's, they still get smoked at parity. Apes/primates are much smarter than cats, except baboons and mandrills, they also get smoked at parity." I get the point here, however, wouldn't many of these examples not exactly be the best analogy here, as both dromaeosaurs and cats/bears are well armed and so I believe the op’s point was that such an advantage like a larger brain with faster thinking would be more significant in that kind of scenario. "In contrast, theropods often had to deal with animals that can defend themselves with tail swipes. Many of those animals like hadrosaurs or tenontosaurus could also defend themselves with kicks as well." That makes me wonder if Machairodonts like Smilodon would also have some advantage there when compared with modern cats because they hunted animals like Doedicurus. Another thing is the way that dromaeosaurids fought. The OP doesn’t think that the method of dromaeosaurids pinning prey under their weight is likely because of how there isn’t any other animal today that does that. I’m not sure how much credibility this holds but if it does that would mean that the Achillobator may not attack the lion by pouncing on top of it. It also seems that stamina may not be as easily given to theropods as before thought because both birds and mammals have equal maximum aerobic capacity despite birds having pneumatic bones and unidirectional breathing. "Link wasn't loading for me but hmmm...it's not like animals can ever go toe-to-toe with or even prey on/defeat animals that are larger-brained/more "intelligent" than themselves. It's not like nature's filled with stuff like - big cats bringing down similar sized pigs (which are apparently really smart animals) - Komodo dragons doing likewise - rock python killing a spotted hyena - constrictors killing or at least breaking even with big cats - crocodiles killing big cats - great whites killing elephant seals (even bulls) and beaked whales - just sharks generally besting dolphins unless the latter are significantly larger - big cats hunting apes oh...never mind. Oh but I'm sure a bear will Batman up a plan as it's wrestling with a beast rapidly stabbing it multiple times in the gut with knives on its feet, raking with meathooks on its fingers, and furiously shaking off fur and flesh with the serrated steak knives in its mouth...right?" Sorry if the link wasn’t working, here is another one: carnivora.net/viewtopic.php?p=219380#p219380I don’t think OP was saying that the carnivorans would make a “genius plan” to kill the theropod, rather that they had an advantage in coordination and generally better intuition and also pointing out that some advantages given to the theropods are not true like “better stamina” or “stronger bones”. However, as discussed in what's posted above by Supercommunist, the carnivorans might not have such an advantage or if they did it wouldn’t be that significant.Brains and intelligence is a very tricky thing, even with modern animals. I have a feeling that a lot of these aspects depend on a lot more complicated factors than we know. On another note, this recent study has given some measurements and allometry based mass estimates for Utahraptor and it's…weird to say the least. It seems the difference in robustity between individuals ( atleast in the femur ) is giant for a reason I don't know. One specimen here was estimated at almost 800 kg, and assuming that the largest femur in length ( 60 cm ) had the same proportions, that's an animal that weighs well over a tonne. Scaling from the other two specimens still gives 550-760 kgs, which is still huge but shows the massive range in robustity. I suspect that one of the femurs may just be damaged or warped but I can't tell from the limited info we have. I haven’t found anything on the femural circumference of byuvp 15465 so if anyone does that would be nice. Just bringing this up in case it makes any impact on Achillobator here, although I don't believe we have a circumference measurement for it either. I haven’t really kept up on the size of the American lion, I just know that it was somewhere between 300-400 kgs. Previous sizes for achillobator ( scaled from Hartman’s Utahraptor, 500 kg ) gets anywhere from 300-330 kgs roughly, but now it seems that it could potentially be larger. In fact it’s technically in the league of Utahraptor, as their femur lengths/widths seem to actually overlap. If that applies, that means it potentially has a massive size advantage against it's opponent if we assign the maximum we have for Utahraptor onto Achillobator. This is the study by the way: www.cambridge.org/core/journals/paleobiology/article/evolution-of-femoral-morphology-in-giant-nonavian-theropod-dinosaurs/2C41BA499BC30AE01060ACF71D2F6263
|
|
|
Post by razor45dino on Jun 5, 2024 7:36:04 GMT 5
"Depends on the Dromaeosaur, depends on the bear, but as I said, I would bet on Achillobator against any bear at parity and on Utahraptor against polar bear at parity (though they probably wouldn't be at parity if we're talking male polar bears). A lot of points made in favour of the bears just seem trivial. IB has already addressed the intelligence thing well enough so I won't get into that, but there's points like bears being super strong, can flip a bison, can just wrestle the raptor down with ease or break its skull with one swipe, whatever. To that, see my above points about Achillobator's legs. Then there's forelimb functionality. Sure the bear had more power and mobility with its forelimbs but Dromaeosaurs didn't need that given the mobility and reach of their neck and jaws and besides, they didn't have to unbalance themselves to use their forelimbs. Then there's the issue of bite force/lethality. Well, according to Sakomoto 2020, animals with similar skull widths (not skull length or body size) tend to have roughly similar bite forces, like he found (subadult) Deinonychus, Dromaeosaurus and asian black bears to have had similar bite forces and they had similar skull widths. A 60 cm long Utahraptor skull was approximately 23 cm wide (using the Gaston mount which seems to be the most up to date version and based on the most actual material), which means that its bite force wouldn't be too far off that of a polar bear with a 26 cm wide skull, and given that such a polar bear would most likely outweigh the Utahraptor, that's pretty impressive. Achillobator's skull might've also gotten up to 60 cm (assuming that the maxilla makes up about half the skull length which seems reasonable) so if it had similar proportions then it would have had a similar bite force too. This is not to mention that Dromaeosaurs had long rows of ziphodont teeth that could inflict massive damage in conjunction with their bite force and postcranial musculature (again, legs). "
Yeah i agree that it would definitely depend on the animals we are talking about, as all 3 groups are fairly diverse. I think I and someone else tried to extrapolate Utahraptor's BF a while ago from Dromaeosaurus. Between 4000-8000 Newtons posterior i think. I wouldn't be surprised it has a higher ( maybe even much higher ) bite force for it's size than a cat or bear, considering just how massive and deadly that skull was.
|
|
|
Post by Shri devi on Jun 5, 2024 9:22:52 GMT 5
"Depends on the Dromaeosaur, depends on the bear, but as I said, I would bet on Achillobator against any bear at parity and on Utahraptor against polar bear at parity (though they probably wouldn't be at parity if we're talking male polar bears). A lot of points made in favour of the bears just seem trivial. IB has already addressed the intelligence thing well enough so I won't get into that, but there's points like bears being super strong, can flip a bison, can just wrestle the raptor down with ease or break its skull with one swipe, whatever. To that, see my above points about Achillobator's legs. Then there's forelimb functionality. Sure the bear had more power and mobility with its forelimbs but Dromaeosaurs didn't need that given the mobility and reach of their neck and jaws and besides, they didn't have to unbalance themselves to use their forelimbs. Then there's the issue of bite force/lethality. Well, according to Sakomoto 2020, animals with similar skull widths (not skull length or body size) tend to have roughly similar bite forces, like he found (subadult) Deinonychus, Dromaeosaurus and asian black bears to have had similar bite forces and they had similar skull widths. A 60 cm long Utahraptor skull was approximately 23 cm wide (using the Gaston mount which seems to be the most up to date version and based on the most actual material), which means that its bite force wouldn't be too far off that of a polar bear with a 26 cm wide skull, and given that such a polar bear would most likely outweigh the Utahraptor, that's pretty impressive. Achillobator's skull might've also gotten up to 60 cm (assuming that the maxilla makes up about half the skull length which seems reasonable) so if it had similar proportions then it would have had a similar bite force too. This is not to mention that Dromaeosaurs had long rows of ziphodont teeth that could inflict massive damage in conjunction with their bite force and postcranial musculature (again, legs). " Yeah i agree that it would definitely depend on the animals we are talking about, as all 3 groups are fairly diverse. I think I and someone else tried to extrapolate Utahraptor's BF a while ago from Dromaeosaurus. Between 4000-8000 Newtons posterior i think. I wouldn't be surprised it has a higher ( maybe even much higher ) bite force for it's size than a cat or bear, considering just how massive and deadly that skull was. TBH I have my doubts about extrapolating from Dromaeosaurus' bite force given that Dromaeosaurus had a fairly expanded adductor chamber while Utahraptor's seems to have been more limited based on a partial brain case found in the Utahraptor block which shows the supratemporal fenestrae being rather constricted anteroposteriorly compared to how expanded it is in Dromaeosaurus. See here:
Note: I don't have a perfect dorsal view of Utahraptor, it is what it is, but the lateral view should show what I'm getting at
Just to show how I've scaled the lateral and dorsal view of each:
And to show how I scaled the lateral views with eachother: It might be safer to extrapolate from Deinonychus and Dromaeosaurus to give a rough lower and higher bound or at least some ballpark values. Scaling from Deinonychus (using skull width since that seems to be a good predictor and using data form Sakamoto 2022 for Deinonychus and the Gaston Mount Utahraptor skull dimensions) gives me 2874 N posterior while scaling from Dromaeosaurus gives me 4413 N, so something in the 3000-4000 N range sounds reasonable?
|
|
|
Post by razor45dino on Jun 5, 2024 17:43:19 GMT 5
"Depends on the Dromaeosaur, depends on the bear, but as I said, I would bet on Achillobator against any bear at parity and on Utahraptor against polar bear at parity (though they probably wouldn't be at parity if we're talking male polar bears). A lot of points made in favour of the bears just seem trivial. IB has already addressed the intelligence thing well enough so I won't get into that, but there's points like bears being super strong, can flip a bison, can just wrestle the raptor down with ease or break its skull with one swipe, whatever. To that, see my above points about Achillobator's legs. Then there's forelimb functionality. Sure the bear had more power and mobility with its forelimbs but Dromaeosaurs didn't need that given the mobility and reach of their neck and jaws and besides, they didn't have to unbalance themselves to use their forelimbs. Then there's the issue of bite force/lethality. Well, according to Sakomoto 2020, animals with similar skull widths (not skull length or body size) tend to have roughly similar bite forces, like he found (subadult) Deinonychus, Dromaeosaurus and asian black bears to have had similar bite forces and they had similar skull widths. A 60 cm long Utahraptor skull was approximately 23 cm wide (using the Gaston mount which seems to be the most up to date version and based on the most actual material), which means that its bite force wouldn't be too far off that of a polar bear with a 26 cm wide skull, and given that such a polar bear would most likely outweigh the Utahraptor, that's pretty impressive. Achillobator's skull might've also gotten up to 60 cm (assuming that the maxilla makes up about half the skull length which seems reasonable) so if it had similar proportions then it would have had a similar bite force too. This is not to mention that Dromaeosaurs had long rows of ziphodont teeth that could inflict massive damage in conjunction with their bite force and postcranial musculature (again, legs). " Yeah i agree that it would definitely depend on the animals we are talking about, as all 3 groups are fairly diverse. I think I and someone else tried to extrapolate Utahraptor's BF a while ago from Dromaeosaurus. Between 4000-8000 Newtons posterior i think. I wouldn't be surprised it has a higher ( maybe even much higher ) bite force for it's size than a cat or bear, considering just how massive and deadly that skull was. TBH I have my doubts about extrapolating from Dromaeosaurus' bite force given that Dromaeosaurus had a fairly expanded adductor chamber while Utahraptor's seems to have been more limited based on a partial brain case found in the Utahraptor block which shows the supratemporal fenestrae being rather constricted anteroposteriorly compared to how expanded it is in Dromaeosaurus. See here:
Note: I don't have a perfect dorsal view of Utahraptor, it is what it is, but the lateral view should show what I'm getting at
Just to show how I've scaled the lateral and dorsal view of each:
And to show how I scaled the lateral views with eachother: It might be safer to extrapolate from Deinonychus and Dromaeosaurus to give a rough lower and higher bound or at least some ballpark values. Scaling from Deinonychus (using skull width since that seems to be a good predictor and using data form Sakamoto 2022 for Deinonychus and the Gaston Mount Utahraptor skull dimensions) gives me 2874 N posterior while scaling from Dromaeosaurus gives me 4413 N, so something in the 3000-4000 N range sounds reasonable? I used a version of Hartman's Utahraptor with dromaeosaurus's skull as its dorsal view ( its skull was 70 cm long and 30 cm wide there ) for lack of a better comparison at the time so that's probably why I got those values. It's kind of surprising the Gaston mount skull is slightly less wide than that, I thought it would be the opposite. I would say though, I wouldn't use Deinonychus I think it is worse to use than Dromaeosaurus, not only is there variation in how people reconstruct the skulls as well as bf estimates it's definitely a lot slimmer of a skull than both. I think the given range is reasonable for a 23 cm wide skull. This is talking about bite force at posterior tooth, btw.
|
|
|
Post by Shri devi on Jun 6, 2024 2:10:24 GMT 5
TBH I have my doubts about extrapolating from Dromaeosaurus' bite force given that Dromaeosaurus had a fairly expanded adductor chamber while Utahraptor's seems to have been more limited based on a partial brain case found in the Utahraptor block which shows the supratemporal fenestrae being rather constricted anteroposteriorly compared to how expanded it is in Dromaeosaurus. See here:
Note: I don't have a perfect dorsal view of Utahraptor, it is what it is, but the lateral view should show what I'm getting at
Just to show how I've scaled the lateral and dorsal view of each:
And to show how I scaled the lateral views with eachother: It might be safer to extrapolate from Deinonychus and Dromaeosaurus to give a rough lower and higher bound or at least some ballpark values. Scaling from Deinonychus (using skull width since that seems to be a good predictor and using data form Sakamoto 2022 for Deinonychus and the Gaston Mount Utahraptor skull dimensions) gives me 2874 N posterior while scaling from Dromaeosaurus gives me 4413 N, so something in the 3000-4000 N range sounds reasonable? I used a version of Hartman's Utahraptor with dromaeosaurus's skull as its dorsal view ( its skull was 70 cm long and 30 cm wide there ) for lack of a better comparison at the time so that's probably why I got those values. It's kind of surprising the Gaston mount skull is slightly less wide than that, I thought it would be the opposite. I would say though, I wouldn't use Deinonychus I think it is worse to use than Dromaeosaurus, not only is there variation in how people reconstruct the skulls as well as bf estimates it's definitely a lot slimmer of a skull than both. I think the given range is reasonable for a 23 cm wide skull. This is talking about bite force at posterior tooth, btw. I've spoken to Jim Kirkland on Twitter he said that the Hartman skeletal, while largely pretty good, has a few issues, including the skull which is too big. The Gaston skull is better in this regards. Regarding Deinonychus, tbh I'm not sure where Sakamoto 2022 got the skull width from. We do have an occiput but it belongs to a not fully grown individual (though I don't believe it was specified at what stage) though the other cranial remains we have mainly come from YPM 5232 and YPM 5210 which are most likely also subadults (with an adult like MCZ 4371 being around 20% larger for comparison) so... Regardless though, I'm not sure about exact bite force estimates (I just extrapolated from Sakamoto 2022 which uses the dry skull method so the numbers I gave (which are also for the posterior bite force) are useful for comparing with other dry skull estimates) but, looking at the skull, I'm fairly confident that it would be a decent bit lower than a scaled up Dromaeosaurus.
|
|
|
Post by razor45dino on Jun 6, 2024 2:30:24 GMT 5
I used a version of Hartman's Utahraptor with dromaeosaurus's skull as its dorsal view ( its skull was 70 cm long and 30 cm wide there ) for lack of a better comparison at the time so that's probably why I got those values. It's kind of surprising the Gaston mount skull is slightly less wide than that, I thought it would be the opposite. I would say though, I wouldn't use Deinonychus I think it is worse to use than Dromaeosaurus, not only is there variation in how people reconstruct the skulls as well as bf estimates it's definitely a lot slimmer of a skull than both. I think the given range is reasonable for a 23 cm wide skull. This is talking about bite force at posterior tooth, btw. I've spoken to Jim Kirkland on Twitter he said that the Hartman skeletal, while largely pretty good, has a few issues, including the skull which is too big. The Gaston skull is better in this regards. Regarding Deinonychus, tbh I'm not sure where Sakamoto 2022 got the skull width from. We do have an occiput but it belongs to a not fully grown individual (though I don't believe it was specified at what stage) though the other cranial remains we have mainly come from YPM 5232 and YPM 5210 which are most likely also subadults (with an adult like MCZ 4371 being around 20% larger for comparison) so... Regardless though, I'm not sure about exact bite force estimates (I just extrapolated from Sakamoto 2022 which uses the dry skull method so the numbers I gave (which are also for the posterior bite force) are useful for comparing with other dry skull estimates) but, looking at the skull, I'm fairly confident that it would be a decent bit lower than a scaled up Dromaeosaurus. yes I was aware that the Hartman' skull was not accurate, but surprised that the skull is oversized, though I guess that makes sense considering the proportions of other dromaeosaurids. I would have believed using using hartman's if anything would have given an underestimate, but it seems not so.
|
|
|
Post by razor45dino on Jun 8, 2024 20:46:05 GMT 5
wow thats big, but why don't skeletals restore the sickle claw like this The keratin sheath length is difficult to predict. There aren't many fossils that gave us any indication how long the keratin sheath is. For this same reason, most theropod depictions didn't have lips until recently. Fossils didn't preserve the lips and so most artists assumed their teeth were exposed like crocodiles. yeah but we have an example right here where the keratin sheath size can be seen, so why don't depictions follow that?
|
|
|
Post by Supercommunist on Jun 9, 2024 4:20:17 GMT 5
The keratin sheath length is difficult to predict. There aren't many fossils that gave us any indication how long the keratin sheath is. For this same reason, most theropod depictions didn't have lips until recently. Fossils didn't preserve the lips and so most artists assumed their teeth were exposed like crocodiles. yeah but we have an example right here where the keratin sheath size can be seen, so why don't depictions follow that? Probably because its a fairly new fossil find and the keratin sheath isn't real easy to see. Even with the photo zoomed it's kind of hard to see it. Saurornitholestes isn't a particularly well known dinosaur either.
|
|
|
Post by Shri devi on Jun 10, 2024 2:56:07 GMT 5
The keratin sheath length is difficult to predict. There aren't many fossils that gave us any indication how long the keratin sheath is. For this same reason, most theropod depictions didn't have lips until recently. Fossils didn't preserve the lips and so most artists assumed their teeth were exposed like crocodiles. yeah but we have an example right here where the keratin sheath size can be seen, so why don't depictions follow that? Jed Taylor's Dromaeosaurs do.
|
|