HOME | DD
RavePaleoArt — Alamosaurus sanjuanensis
Published: 2017-06-12 09:51:56 +0000 UTC; Views: 8841; Favourites: 274; Downloads: 18
Redirect to original
Description
Late Cretaceous southern North America during dry season. A pair of tyrannosaurs are being disturbed while stalking a herd of Torosaurus utahensis, by the arrival of a large bull Alamosaurus sanjuanensis at a waterhole.I am aware that in light of resent tyrannosaur discoveries, this depiction is probably outdated, if of course it turns out that T. rex was scaly after all.
Related content
Comments: 42
👍: 0 ⏩: 2
👍: 0 ⏩: 0
👍: 1 ⏩: 1
👍: 0 ⏩: 0
This is actually one of my favorite scenes with Alamosaurus (my favorite sauropod anyway), because it depicts a late Cretaceous landscape, the ecology of it.
However, I wonder to what extent the semi-arid and dry season picture of the late Cretaceous southern US is entirely correct. I know it has formerly been considered that way, however, more comprehensive and more recent studies suggest that the climate and ecology of the latest Cretaceous (Maastrichtian) southern US was actually more like sub-humid or seasonally (maybe monsoonal) humid. For sure it, in particular the Javelina formation, was dominated by large trees (not so surprising if it was also dominated by large sauropods).
A very interesting paper in this context is: LATE CRETACEOUS WOODY DICOTS FROM THE AGUJA AND JAVELINA FORMATIONS, BIG BEND NATIONAL PARK, TEXAS, USA; by E. A. Wheeler & T. M. Lehman, 2000.
A few interesting quotes about the Javelina formation:
“Javelinoxylon wood (and Paraphyllanthoxylon, abundant) occurs at all levels where remains of the giant sauropod Alamosaurus occur.”
“However, growth rings are indistinct to absent in Javelinoxylon (…), and this absence does not suggest seasonal climates.”
“Logs of Javelinoxylon from Big Bend exceeded 70 cm in diameter (…). Additional Big Bend woods described in this report show that dicotyledonous trees with large diameter trunks were not only present, but locally dominated Cretaceous forests in this region.”
“Javelinoxylon trees (Maastrichtian age) which reached over 70 cm diameter are estimated to also be over 40 metres high.”
Several other large tree and vine species are described.
And fascinating is the following observation:
“Most of the dicot wood types of Big Bend are characterized by high proportions of parenchyma”.
“Larger or more abundant (parenchyma) rays give greater strength to wood when pulled in the radial direction. It is possible that this would be advantageous for trees that had to survive aggressive browsing by large dinosaur herbivores.”
So, I get the impression of a sub-humid subtropical Alamosaurus (+ ceratopsian) dominated woodland, though not as moist and densely vegetated as the northern US + Canada, which was more duckbill dominated.
👍: 0 ⏩: 1
Further to my previous comment, what I would actually really like to know are answers to the following 2 questions:
1) Did Alamosaurus make it into eastern North America (Appalachia) in the latest Cretaceous? This one may be hard or impossible to answer at this moment. AFAIK no sauropod remains have ever been found of the latest Cretaceous in Appalachia. All sauropods fossils there predate the (25-30 million year) sauropod hiatus, i.e. they are early-mid Cretaceous, not Campanian or Maastrichtian.
Since the Western Interior Seaway (WIS) closed around mid-Maastrichtian, and Alamosaurus appeared around that time or even just before, one would expect them to have migrated eastward as well.
2) I have seen mentioning of an ecological analysis stating that at any one given time there would have been a population of at least 350,000 (adult and sub-adult) Alamosaurus in (western) Texas. What is the source of that information, i.e. does anyone know the article/paper?
👍: 0 ⏩: 0
Fantasticly done. Also they were scaled but not in the way you think
www.google.com/url?sa=t&source…
👍: 0 ⏩: 0
Wait, couldn't they of been mostly scaly with some feathers on the back as a cape and not fully scaly anyways, this is absolutely amazing art!!
👍: 0 ⏩: 1
Actually they kinda are here see for your self.
www.google.com/url?sa=t&source…
👍: 0 ⏩: 0
Although, the way you've drawn it, the tyrannosairs cuold just as easily be interpreted as having patterned scales... beautiful pattern, either way.
👍: 0 ⏩: 0
www.google.com/url?sa=t&source…
👍: 0 ⏩: 1
I don't agree with the guy on the no feathers thing.
👍: 0 ⏩: 1
I really like you T. Utahensis depiction! People usually get the tails way too long and the skull too short, nice work.
👍: 0 ⏩: 0
It's cool to see Tyrannosaurus in a semi arid habitat, which it also apparently inhabited.
👍: 0 ⏩: 0
This looks really cool, although it's doubtful Torosaurus lived in herds.
👍: 0 ⏩: 0
The only impressions of T-rex skin we have are from the belly and underside of the tail, places which even on dinosaurs which we know have feathers tended to be scaly
👍: 0 ⏩: 0
Scales and feathers aren't mutually exclusive. Birds have scales and feathers so why can't Tyrannosaurs?
👍: 0 ⏩: 1
That's very much true, but a recently published paper argues that at least the larger Tyrannosauridae likely would've been scaly, at least for the most part.
rsbl.royalsocietypublishing.or…
👍: 0 ⏩: 3
youtu.be/CxE68c9rYa0
youtu.be/uM5JN__15-g
These videos are both examined by Trey the Explainer, but the top one is the debunking of the article you had mentioned while the bottom one is an earlier examination of tyrannosaurus having feathers, but at 29:35, he majorly debunks myths of excuses that tyrannosaurs wouldn't have feathers.
👍: 0 ⏩: 0
This paper is highly questionable
👍: 0 ⏩: 0
I know about the paper, I was referring to it. But yet again we get another portion of scaly skin from apart of the body that we already know to not been heavily feathered. Saying that T. rex must be completely scaly or completely feathered is ridiculous, life is never black and white. You'd think the publishers would know this. It was probably feathered just as modern dinosaurs are, naked legs, scaly heads, feathered body.
Hell, i'm even willing to entertain the idea of two different variations or species of the same genus of Tyrannosaurus, being feathered according to their environment. A southern species like shown in your artwork that was less feathered (while still retaining some) due to the hot climate of the south. And a more feathered species native to hell creek that had a denser coat because of the colder climate and long periods of darkness during the winter.
Remember dinosaurs are animals not machines. They aren't bound to a certain style or look or behavior. Nature is wild and breaks the 'rules' constantly.
👍: 0 ⏩: 0
That Alamosaurus is amazing. It looks so powerful and unbeatable! Great work.
👍: 0 ⏩: 1
Indeed a true american giant.
👍: 0 ⏩: 0
Well not yet though, but the feathering includes on the back, upper neck, part of the face(speculative), and partially the tail. If anything, a feathered tyrannosaurid is still plausible but a scaly/naked skinned one is now just as plausible from the data given.
👍: 0 ⏩: 1
www.google.com/url?sa=t&source…
👍: 0 ⏩: 1
I've seen the video, long after the blogpost the team posted. It's been well more than a year after the study, perspectives have changed. This comment(or correction these comments) do not reflect how we currently view the animal's extensive integument, let alone is it fully understood.
And even after all that, you still replied to such old comments? With a YouTube video(granted they always cite their sources and are well educated, but still...)??
👍: 0 ⏩: 1
I'm sorry about that I really should have thought about it a bit more. My apologies
👍: 0 ⏩: 1
It's fine. But it gets annoying...
Apology accepted though...
👍: 0 ⏩: 1
Thanks. Happy new year by the way.
👍: 0 ⏩: 1