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My favourite subject.
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24-02-2018 10:28pm#1
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Ugh, so much wrong with the second video. It was obviously made hastily by someone who has never opened a book on prehistoric life, and only skimmed through the Internet for the basics while still managing to get almost everything wrong.
He keeps calling plesiosaurs, ichthyosaurs and other sea animals "dinosaurs" (even Basilosaurus... before he calls it a whale moments later!) s, includes freshwater animals as if they were marine (Hyneria, Titanoboa, Sarcosuchus), includes Pliosaurus twice (Predator X is not "related to Pliosaurus", it IS Pliosaurus!), includes Henodus, a vegetarian, and calls it a deadly predator, and most egregiously, leaves C. megalodon completely out! Where is C. megalodon??
Also, he implies that Livyatan's main difference from modern sperm whales was its size (they're actually within the same size range), and same for the "Giant Stingray" (in which he can´t seem to decide whether he's talking about stingrays or manta rays). Most of the sizes he gives are off (Plesiosaurus was small, 3.5 meters or so, not a 25 meter long giant, and Hyneria was actually much larger than 2 meters), and at least one entry (the supposed Colossal Squid ancestor) is completely unknown from the fossil record (there ARE known fossils of giant cephalopods, but they're not closely related to the Colossal Squid). I'm also not sure about "Pelagicetus" being a real animal. And even if it did exist it couldn´t have eaten dolphins as claimed, because basilosaurs went extinct long before the first dolphins appeared.
When talking about Cetotherium, he missed the opportunity to mention that the pygmy right whale Caperea marginata, a very rarely seen cetacean, was finally examined properly in 2012 thanks to a beached specimen and found to be the last surviving member of the Cetotheriidae family, believed to have been extinct for millions of years.
Cetotheres were also NOT the first filter feeding whales.
Finally, many of the pictures he uses are completely unrelated to the animal he's talking about. He uses Pachyrhachis for Madtsoia, for example, and Madtsoia wasn´t even marine. There WERE true sea serpents, but he failed to mention any of them.0 -
Ugh, so much wrong with the second video. It was obviously made hastily by someone who has never opened a book on prehistoric life, and only skimmed through the Internet for the basics while still managing to get almost everything wrong.
He keeps calling plesiosaurs, ichthyosaurs and other sea animals "dinosaurs" (even Basilosaurus... before he calls it a whale moments later!) s, includes freshwater animals as if they were marine (Hyneria, Titanoboa, Sarcosuchus), includes Pliosaurus twice (Predator X is not "related to Pliosaurus", it IS Pliosaurus!), includes Henodus, a vegetarian, and calls it a deadly predator, and most egregiously, leaves C. megalodon completely out! Where is C. megalodon??
Also, he implies that Livyatan's main difference from modern sperm whales was its size (they're actually within the same size range), and same for the "Giant Stingray" (in which he can´t seem to decide whether he's talking about stingrays or manta rays). Most of the sizes he gives are off (Plesiosaurus was small, 3.5 meters or so, not a 25 meter long giant, and Hyneria was actually much larger than 2 meters), and at least one entry (the supposed Colossal Squid ancestor) is completely unknown from the fossil record (there ARE known fossils of giant cephalopods, but they're not closely related to the Colossal Squid). I'm also not sure about "Pelagicetus" being a real animal. And even if it did exist it couldn´t have eaten dolphins as claimed, because basilosaurs went extinct long before the first dolphins appeared.
When talking about Cetotherium, he missed the opportunity to mention that the pygmy right whale Caperea marginata, a very rarely seen cetacean, was finally examined properly in 2012 thanks to a beached specimen and found to be the last surviving member of the Cetotheriidae family, believed to have been extinct for millions of years.
Cetotheres were also NOT the first filter feeding whales.
Finally, many of the pictures he uses are completely unrelated to the animal he's talking about. He uses Pachyrhachis for Madtsoia, for example, and Madtsoia wasn´t even marine. There WERE true sea serpents, but he failed to mention any of them.
Yes yes yes I am not alone then after I posted it it was in my head to take it down again but then I thought to myself let it ride, either I am wrong :eek: or Adam will tear it apart. lol at least we are thinking along similar lines and I am sorry for offending your sensibilities.
:D:D 0 -
Am I really that predictable? :B
Re: Liopleurodon, I'm guessing it didn´t get included because of the recent downsizing? Most sources suggest Liopleurodon would've been within the size range of today's orca (6-7, maybe 9-10 meters tops). The 25 meter long figure made popular by Walking with Dinosaurs was apparently based on a measly skull fragment found in England which was originally interpreted as coming from a pliosaur considerably larger than any previously found. Apparently, a length of 30 meters was considered at one point making it the largest sea reptile known. However the remains are very fragmentary and we can´t tell for sure whether it belonged to Liopleurodon or how big it truly was.
From what I've read, the biggest pliosaurs known by decent remains would be Pliosaurus and Kronosaurus. Both Pliosaurus kevani and Pliosaurus funkei ("Predator X") are known from incomplete remains but it does seem like their skulls were over 2 meters long. Pliosaurus rossicus (formerly Liopleurodon rossicus) is around 9.6 meters long (and was found along with a colossal ichthyosaur probably 11 meters long, but nobody talks about ichthyosaurs
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Kronosaurus queenslandicus was originally said to have a skull up to 3.7 meters long, but more recently it was downsized to maybe 2.8 meters (still much bigger than any giant theropod skull known). It also seems that the famous mounted specimen was reconstructed with too many vertebrae so it wouldn´t have been up to 17 meters long as was once claimed, but maybe closer to 9-10 meters. The South American species Kronosaurus boyacensis has been estimated at 9 meters with a 2.4 meter skull (they had bigger skulls proportionally than Pliosaurus or Liopleurodon, it seems).
So all things considered, it seems the biggest pliosaurs known thus far from decent remains would've been about as big as a male orca, which is nothing to scoff at (they'd still have little trouble eating a human, which I think we all agree is the important thing).
It's not impossible that some pliosaurs grew bigger than this, as there are some specimens such as Pliosaurus carpenteri and the near-mythical Monster of Aramberri that are very large in size (11 meter estimate for the latter it seems), yet their vertebrae suggest they were not fully grown. Either the vertebrae on these animals never fully fused, or they still had growing to do in which case we simply haven´t found the really huge ones. Keep in mind that the Monster of Aramberri was reported to have bite marks from what may have been an even larger pliosaur.0 -
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I seriously doubt any of the mentioned animals sans a large Livyatan could be considered a rival to C. megalodon.
As with the last video, most of the images he used for some of the animals (like Rhamphosuchus) actually depict other creatures.
to be fair I only posted that video to show the bravery of the cameraman:D 0 -
That reminds me of something I've always wondered. Modern day cetaceans are unusually tolerant of humans compared to other wild animals. They have the power to do lots of harm if they want to, and some of them- like orcas- feed on mammals (like seals and sea lions often larger and better armed than humans), yet attacks by any cetacean species on humans are exceedingly rare (at least in the wild).
My question is, do you think prehistoric cetaceans would extend us the same courtesy? What would happen, for example, if you went swimming with one of the scary whales and pseudo-dolphins that had zero experience with humans as we hadn´t evolved yet?
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Seeing as ichthyosaurs existed for so long there may have been exceptions, but they're supposed to have been deaf- something about their ear bones being too thick and too deep in the skull. This I think stems from a study conducted on a Platypterygius. The same study suggests that there may have been either electroreceptors or mechanoreceptors on the ichthyosaur's lower jaw. But it seems pretty obvious that the ichthyosaur's main sense was eyesight.
If ichthyosaurs were indeed deaf, then there's virtually no chance of them having a high frequency sonar like whales, although it is not impossible that they'd be sensitive to low frequency vibrations, as are snakes (another mostly deaf reptile). Which in turn suggests sounds were probably not very important when it came to ichthyosaur communication, or if they were, it would've been infrasounds, so they would've seem mostly silent to us. All speculation, tho.
Mosasaurs are interesting; some sources suggest they had poor senses of sight and hearing, and even, that their olfactory bulb was poorly developed. However, they do seem to have had a vomeronasal organ, meaning they probably also had a forked tongue like their close relatives- monitor lizards and snakes-, allowing them to taste their way to prey.
That being said, the skull of Phosphorosaurus makes it abundantly clear that this particular mosasaur at least was well adapted to hunting by sight, probably at night or at great depths.
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Relevant to this thread; recent microtomography reveals senses and adaptations of Nothosaurus:
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0188509
The study suggests Nothosaurus had good eyesight (probably binocular vision even), but the eyes were pretty much fixed in their orbits, and the vomeronasal organ was atrophied meaning no forked tongue for these guys. Also, salt glands.
Nothosaurus was apparently a succesful predator, widely spread and could grow up to 7 meters long (at least the species N. zhangi from China did).
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