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21-07-2019, 16:28   #91
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The snorkel idea was once suggested for Parasaurolophus, perhaps the most iconic of the hadrosaurs (although one relatively rare in the fossil record).

The idea has long been discarded due to several reasons...
Good to know. Thanks Adam.
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27-07-2019, 22:30   #92
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Did one species have a snorkel on the top of its head? For breathing at waterline, with rest of animal below surface?
IIRC 2 meters is the maximum depth underwater humans can breath through a tube to the surface.

And the guy who tried it died shortly afterwards, so do not try at home.


Human lungs aren't made for that differential.
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27-07-2019, 23:12   #93
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I wonder what would happen in this scenario then :B
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27-07-2019, 23:14   #94
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https://dino.lindahall.org/img/bur1m.jpg

I wonder what would happen in this scenario then :B

In two words I can tell you what's the matter with it: It's im-possible.

- Samuel Goldwyn
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05-08-2019, 20:37   #95
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Hapless Prosaurolophus ended up at sea

But that's good news for fossil preservation:

https://royaltyrrellmuseum.wpcomstag...play-features/

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05-08-2019, 20:41   #96
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Gobihadros, a new hadrosaur from Mongolia

Or hadrosauroid. Skeleton said to be nearly complete and as well preserved as if it had died days ago, thus allowing for great, accurate reconstruction:

https://journals.plos.org/plosone/ar...l.pone.0208480

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19-10-2019, 20:24   #97
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From the North Dakota Geological Survey's Paleontology Resource Protection Program's Twitter account, comes this very interesting picture which shows the hand of famous Edmontosaurus "mummy" Dakota, one of the best preserved dinosaurs in the world.

The picture shows that we have been reconstructing hadrosaur "hands" the wrong way; instead of three separate digits each ending in one small hoof, it appears these animals had all three main digits completely covered on a skin and flesh "mitten", and only the third digit had a big, horse-like, weight-bearing hoof. So, externally, the creature would only have one apparent hoofed toe, and a small, spike-like "pinky" that didn´t touch the ground.



Yet another example of how little we actually know about dinosaurs- even "classic" ones like Edmontosaurus-, and how different they would look with all their fleshy bits on.

Last edited by Adam Khor; 19-10-2019 at 20:31.
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02-03-2020, 05:18   #98
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Big news! Cartilage cells with traces of the original proteins/DNA found in juvenile Hypacrosaurus fossils!



https://newatlas.com/science/dinosau...teins-fossils/

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These particular specimens were “nestlings”, meaning that at time of death they weren’t yet old enough to leave the nest.

Inside the skull fragments, the team spotted evidence of extremely well-preserved cartilage cells. Two of them were still linked in a way that resembles the final stages of cell division, while another contained structures that look like chromosomes.

The next step was to check whether any original molecules or proteins could still be preserved, and to do so the team conducted two detailed analyses on other skulls from the same nesting ground, and compared the results to samples from young emu skulls that are (obviously) much more recent.

The first was an immunological test, which involves applying a substance that will react if it detects antibodies from a particular cell type. In this case, the test reacted to antibodies of Collagen II, a protein commonly found in the cartilage of animals. This, the team says, suggests that remnants of the original proteins are still present.

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Understandably, the reaction was far fainter for the dinosaur samples than the emus. The dinosaurs’ staining was also localized in one spot, where as in the emu it was spread across the whole sample.

In the second test, the team hunted for dinosaur DNA. They isolated individual cartilage cells from the Hypacrosaurus, and applied two different staining substances that bind to DNA fragments. And sure enough, the staining occurred in the same pattern expected for modern cells.

The implications of potentially finding DNA in these samples are huge. Current thinking says that DNA can only persist for about a million years maximum – but these fossils are 75 million years old.

"These new exciting results add to growing evidence that cells and some of their biomolecules can persist in deep-time,” says Alida Bailleul, co-lead author of the study. “They suggest DNA can preserve for tens of millions of years, and we hope that this study will encourage scientists working on ancient DNA to push current limits and to use new methodology in order to reveal all the unknown molecular secrets that ancient tissues have.”


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While Jurassic Park remains firmly in the realm of fiction, the possibility that dinosaur DNA and organic molecules could persist for tens of millions of years is still fascinating, and it could teach us far more about these captivating, ancient creatures.
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10-03-2020, 18:57   #99
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Strontium isotopes reveal migratory behavior of late Cretaceous hadrosaurs:

https://royalsocietypublishing.org/d...rsbl.2019.0930

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Dinosaur migration patterns are very difficult to determine, often relying solely on the geographical distribution of fossils. Unfortunately, it is generally not possible to determine if a fossil taxon's geographical distribution is the result of migration or simply a wide distribution. Whereas some attempts have been made to use isotopic systems to determine migratory patterns in dinosaurs, these methods have yet to achieve wider usage in the study of dinosaur ecology. Here, we have used strontium isotope ratios from fossil enamel to reconstruct the movements of an individual hadrosaur from Dinosaur Provincial Park in Alberta, Canada. Results from this study are consistent with a range or migratory pattern between Dinosaur Provincial Park and a contemporaneous locality in the South Saskatchewan River area, Alberta, Canada. This represents a minimum distance of approximately 80 km, which is consistent with migrations seen in modern elephants. These results suggest the continent-wide distribution of some hadrosaur species in the Late Cretaceous of North America is not the result of extremely long-range migratory behaviours.
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10-03-2020, 19:10   #100
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More on the cells and cartilage traces supposedly found in Hypacrosaurus remains (naturally some paleontologists are skeptical, as they were with the T. rex soft tissue a few years ago).

https://gizmodo.com/paleontologists-...lls-1842034627

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07-05-2020, 01:07   #101
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"New" Arctic hadrosaurs turn out to be Edmontosaurus after all.

https://phys.org/news/2020-05-arctic...retaceous.html

The so called "Ugrunaaluk" was described in 2015. It appears now that it's just Edmontosaurus (aka Anatosaurus aka Anatotitan aka Trachodon), the same duckbilled dinosaur that coexisted with (and was preyed on by) Tyrannosaurus rex further south.

Edmontosaurus thus becomes one of the most widespread hadrosaurs known, especially if other very similar hadrosaurs from Asia turn out to be part of this genus as well.

It was also one of the largest, with some North American specimens reaching up to 12 or maybe even 15 m long, and Asian ones potentially even larger ("Shantungosaurus" , which may well be an Asian Edmontosaurus).

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01-06-2020, 02:24   #102
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Like modern reptiles, hadrosaurs did not have intervertebral discs, suggests study on T. rex bitten specimen:

https://onlinelibrary.wiley.com/doi/10.1111/ahe.12573

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The flat‐end surfaces of dinosaur vertebral centra led to the presumption that intervertebral discs occupied the space between their vertebrae. A set of fused hadrosaur vertebrae allowed that hypothesis to be tested. The Tyrannosaurus rex responsible for this pathology did not escape unscathed. It left behind a tooth crown that had fractured. Fragments of that tooth were scattered through the intervertebral space, evidencing that there was no solid structure to impede its movement. That eliminates the possibility of an intervertebral disc and instead proves the presence of an articular space, similar to that in modern reptiles, but at variance to what is noted in birds. While avian cervical vertebral centra appear to be separated by diarthrodial joints, the preponderance of their thoracic vertebral centra is not separated by synovial joints.
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08-09-2020, 20:41   #103
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Early Cretaceous ornithopods found in China, described as new species Changmiania liaoningensis. Changmian means "eternal sleep" in Chinese, as the creatures were apparently preserved by volcanic ash while sleeping inside their burrow. The animal shows adaptations to a fossorial (burrowing) lifestyle including a shovel-shaped nose and thick, powerful neck and shoulders. This adds to the growing evidence that small ornithischians were often living in burrows.

The animal appears to be a most primitive form of ornithopod despite being contemporary with Iguanodon.

https://www.naturalsciences.be/en/news/item/19274

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