Prehistoric Life/Dinosaurs/Sauropods: Difference between revisions

* Which is the most common sauropod in the USA, ''[[Stock Dinosaurs|Apatosaurus]]'', ''[[Stock Dinosaurs|Brachiosaurus]]'', or ''[[Stock Dinosaurs|Diplodocus]]''? None of them. It was ''Camarasaurus''. This dinosaur was as enormous as the former, and shared their same habitat in which other two popular dinosaurs lived, ''[[Stock Dinosaurs|Stegosaurus]]'' and ''[[Stock Dinosaurs|Allosaurus]]''; and yet, when was the last time you’ve heard “Camarasaurus” in a film/cartoon/comic? Even the famous [[Speculative Documentary]] ''[[Walking Withwith Dinosaurs]]'' has totally ignored it, preferring its stock cousins instead. The misfortune of ''Camarasaurus'' is probably due to not detaining any size-record among sauropods: it has never been either “the longest” like ''Diplodocus'', or “the tallest/heaviest” like ''Brachiosaurus''. Discovered during the Bone Wars, ''Camarasaurus'' is considered by some a rather unsauropod-like sauropod, because of its relatively large head and its much-shorter neck compared to most other sauropods. It tended to be confused with the so-called “Brontosaurus” in the past, because the classic brontosaur portraits have a round head and a short, blunt tail, just like [[Real Life]] camarasaurs. However, ''Camarasaurus'' was more related to ''Brachiosaurus'' than to ''Apatosaurus''. Both the brachiosaur and the camarasaur had short, boxy skull with wide nasal openings, a nasal crest, and relatively large teeth which bordered the whole jaws - the ''Diplodocus'' and ''Apatosaurus'' skull was longer and flatter with peg-like teeth only on the jaw-tips. The four legs of ''Camarasaurus'' were about the same length, and its back was perfectly horizontal and perhaps even a bit taller on the shoulders: ''Apatosaurus'' and ''Diplodocus'' has shorter forelimbs than hindlimbs, and their back had a convex silhouette with the tallest point on the ''hips''.

* [[Overshadowed Byby Awesome]] seems a common trope among dinosaurs. We see a dinosaur, remain struck by its awesomeness… but later, another similar yet even cooler dinosaur takes its place in our mind. ''Barosaurus'' could be an example. 8/9 m long, its neck was one of the longest in the whole Animal Kingdom, but is definitively overshadowed by the 12/15 m long neck of ''Mamenchisaurus'' (as well as that of the brachiosaurs). Discovered in USA at the end of the Bone Wars, ''Barosaurus'' was the closest relative of ''Diplodocus'', and lived as well in Late Jurassic North America; some possible remains from Africa are also known, but are fragmentary and undiagnostic. ''Barosaurus'' was virtually identical to ''Diplodocus'' except for its shorter tail counterbalanced by the longer neck. Its was one of the longest sauropods, only a bit shorter than a diplodocus. ''Barosaurus'' means “heavy lizard”: though apt for a sauropod, is not totally appropriate. Having the same slender frame of ''Diplodocus'', the barosaur weighed less than other sauropods. Its lower notoriety is probably due to the fact ''Barosaurus'' remains are less abundant than the ''Diplodocus'' ones. However, ''Barosaurus'' has gained more fame when a barosaur skeleton was mounted in the American Museum of Natural History in the 1980s. This skeleton is the dino-star of the museum, being mounted erected on the hindlimbs and the tail; 15 m tall, is shown defending its youngster from an attacking ''Allosaurus''. In the same years, one bizarre suggestion was made about its physiology: with such a long neck, ''Barosaurus'' may have had eight hearts to pump blood up to its lofty head. There isn’t any evidence for this idea, which is now generally discarded as “weird fantasy”.

* Which were the biggest animals ever, whales or dinosaurs? Hard question, depends on what criterium you want to use. ''Cetiosaurus'', the first sauropod ever described, just means “whale-lizard”. But this is not a mere reference to its huge size; it was ''literally'' believed a whale-thing at one point. First found in 1842 in England slightly after Richard Owen coined the word “dinosaur”, its first remains were so incomplete that Owen couldn’t believe such a heavy animal could live on land. Since limb bones were missing, he thought the owner was a non-dinosaurian ''marine reptile'' (remember sea-reptiles were already very well-known at the time). When the limb bones were discovered several decades after, the familiar image of an elephantine “reptile” with long neck and tail came to light. Though not a Wastebin-taxon like ''[[Stock Dinosaurs|Megalosaurus]]'', ''Cetiosaurus'' could thus be seen as its sauropodian equivalent - incidentally, lived just alongside ''Megalosaurus'' in Middle Jurassic Europe, but has been found in North Africa too. ''Cetiosaurus'' has been the archetypical “basal” sauropod, and lived ''before'' the Stock Trio. Among the cetiosaur's primitive traits, it had compact vertebrae instead of hollow - cavities in the backbone is a typical feature of more evolved sauropods like ''Apatosaurus, Diplodocus, Brachiosaurus'' and ''Camarasaurus'' (the latter’s name just meaning [[Exactly What It Says Onon the Tin|lizard with cavities]]). Unfortunately for ''Cetiosaurus'', these sauropods were discovered in North America just in the period of the former’s correct interpretation, Their bigger size and/or their greater completeness meant ''Cetiosaurus'' was progressively put under the table. Making things worse, the cetiosaur has also a very generic look with no external traits that would make it recognizable. In short, this “whale of dinosaur” was predestined to become an only-book animal.

* “Titanosaur” is a often-heard name in documentaries, books and sometimes in pop-media: what is it exactly a titanosaur? Well, it has actually ''two'' meanings. The more strict one indicates a precise genus of Late Cretaceous dinosaur, ''Titanosaurus'', the first sauropod discovered in India (and Asia), in year 1877. Ironically, it’s actually is one of the most fragmentary sauropods, known only from few vertebrae and some other material, but was treated as one of the two most classic dinosaurian “wastebins” together with “[[Stock Dinosaurs|Megalosaurus]]”: to the point that ''Titanosaurus''es cropped up everywhere in the world - now they are regarded either dubious, or reclassified in new genera. The second meaning indicates the sauropod subgroup including the eponymous genus above: [[Exactly What It Says Onon the Tin|Titanosaurs]]. They were a very abundant and widespread dinosaur group in Cretaceous, expecially the Late one; here we list only some noticeable examples. There were not only giants like ''[[Stock Dinosaurs|Argentinosaurus]]'', ''[[Stock Dinosaurs|Paralititan]]'', or ''Antarctosaurus'' (the latter is known since the start of the XX century, hence its generic name “Southern Lizard”). There was also an animal like ''Magyarosaurus'', a [[Oxymoronic Being|dwarf sauropod]] ''only 6 m long'', which reduced its size to survive in small European islands. Most titanosaurs, however, were far from these extremes. The armoured ''Saltasaurus'' and the [[The Unpronounceable|almost unutterable]] ''Opisthocoelicaudia'' were 12 m long. Ironically, despite the high number of described species, titanosaur remains are very scant. Just as an example, ''Opisthocoelicaudia'' from Late Cretaceous Mongolia is considered one of the most complete, with well-preserved body, limbs and tail… but its head and neck are unknown. Even though most titanosaurian remains are from South America (expecially Argentina), they have been found in most parts of the world. Both ''Hypselosaurus'' and ''Ampelosaurus'' come from France; the latter’s status as “the most complete French sauropod” has made it a sort of national celebrity. ''Hypselosaurus'' is far more fragmentary, but is famous because is classically thought the source of some large fossil eggs found in the XIX century; they are reputed the biggest dinosaurian eggs ever found, and yet they’re ''only one foot long'' - not exactly like those man-sized objects seen in cartoons. <ref> Technically, they weren’t the biggest dinosaur eggs: the famous recently-extinct “[[wikipedia:Elephant bird|Elephant Bird]]” from Madagascar laid the biggest known eggs in the whole animal kingdom: up to 2 ft long.</ref>. Among titanosaurs which fell in the ''Titanosaurus''-Wastebasket, the most astonishing is ''Isisaurus'' from India. With its thick neck, short tail and strongly sloping backbone, it was the most giraffe-like sauropod known to date, even more than the well-known brachiosaurids. And what about North America? Did any titanosaur live here, along with T. rexes and Triceratops? Yes, it did, but was the only one known: ''Alamosaurus'', possibly a isolated migrant originary from South America. Even though is known only from (again…) not-complete remains, its status of “the only one who met [[Tyrannosaurus Rex]] in [[Real Life]]!” (and its “token sauropod” appearance as well) has made it the perfect [[Hand Wave]] for those artists/writers who have fun to portray ''Apatosaurus'' and ''Tyrannosaurus'' [[Misplaced Wildlife|living]] [[Anachronism Stew|side-by-side]]. Considering [[Sarcasm Mode|the extreme rarity]] of this eventuality, this would make ''Alamosaurus'', not “Brontosaurus”, [[Unfortunate Implications|the real Great-Stock sauropod...]]

* While Diplodocoids are abundant, Brachiosaurids are much rarer. Most described species are fragmentary, and with their appearance unknown; take ''[[Stock Dinosaurs|Sauroposeidon]]'' as example. We can mention, because of their historical relevance, ''Astrodon'' and ''Pelorosaurus''. The former is the first sauropod found in North America (even before the Bone Wars), but is known mainly from teeth; it’s thought a “small” sauropod which lived in Early Cretaceous along ''Deinonychus'' and .''Utahraptor''. The much bigger ''Pelorosaurus'' (like most non-stock brachiosaurids, lived in Early Cretaceous) was the second sauropod described from Europe, and lived together with ''Iguanodon''. Being its remains very scanty, it too was treated as a Waste-Basket taxon like ''Titanosaurus'': one of these former “pelorosaurs” is the dubious but coolly-named "Gigantosaurus" (not ''[[Stock Dinosaurs|Giganotosaurus]]''). Together, Brachiosaurids, Titanosaurs, ''Camarasaurus'' and others make the Macronarians, one of the two great sauropodian subgroups together with Diplodocoids. Another macronarian which deserve a mention is ''Euhelopus''. The first-found sauropod in China, similar to a miniaturized ''Mamenchisaurus'', it could have been the model for [[Walking Withwith Dinosaurs|Prehistoric Park]]’s “titanosaurs”, being the most classic among Asian Early Cretaceous sauropods.

* Not every sauropod is either Diplodocoid or Macronarian. Many were more primitive than both. ''Cetiosaurus'' and ''Mamenchisaurus'' have already been mentioned: another relevant basal sauropod is ''Shunosaurus'', from Chinese Middle Jurassic. Rather small (10 m long) and short-necked, it’s worthy of note for two things: its bony-club on its tailtip surrounded by four short spikes, resembling a combination between a Stegosaurian and Ankylosaurian tail; and the fact that, with its 20 or more skeletons known, ''Shunosaurus'' is one of the most common sauropod in fossil record, rivalling ''Camarasaurus''. The shunosaur pertains to a Asian sauropod subgroup which included also ''Mamenchisaurus'' and another very similar animal, ''Omeisaurus'' (several species are known from the latter, and yet is not a common sight in books). Outside Asia, primitive sauropods include ''Patagosaurus'' from [[Exactly What It Says Onon the Tin|Patagonia]] and ''Jobaria'' from Africa – both Middle Jurassic, even though the latter was believed Cretaceous, thus a [[Science Marches On|late-surviving form]]. Yet, there were even more basal sauropods other than these: ''Vulcanodon'' and ''Barapasaurus'' are two main examples. Both from Early Jurassic, they still had “prosauropod” traits in their skeletons, but their external shape was already sauropodian, with pillar-like limbs. While ''Vulcanodon'' (whose strange name means “volcano tooth”) was very small for a sauropod (6 m long, less than a plateosaur), ''Barapasaurus'' (not to be confounded with ''Barosaurus'') was the first known sauropod to have reached the classic huge sauropodian size (18 m long). It’s also one of the few dinosaurs from India, while the vulcanodont was Southern African and lived alongside the well-known prosauropod ''Massospondylus''.