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Is this one a bit better? I'm still ironing out some stuff tho

https://sketchfab.com/models/b5a4825a22ed469fa9f797068a8309cd

And this Coelophysis

tigris115 wrote:

Is this one a bit better? I'm still ironing out some stuff tho

https://sketchfab.com/models/b5a4825a22ed469fa9f797068a8309cd

And this Coelophysis

The Coelophysis is good. As for Sue, the legs from the knees down need far more muscle mass but other then that, it's much improved.

With the robust and gracile forms of C. bauri, which one was the male or female. I need to know because when I send the models to be skinned, I want muh dimporphism

It was originally concluded that the gracile morph was female. However, it has since been determined that Coelophysis had a highly variable growth pattern, and that the dimorphism is likely a difference between mature and immature forms. Some of them grew large before they took on the mature form, and some made that transition at a smaller size.

So the robust was just the mature form while the gracile was the immature form?

The study does not make abundantly clear which morph they believe to be the mature form. However, I'd be inclined to say that the gracile was the mature form while the robust was the immature. This is because the gracile form has a fused sacrum and the robust does not, and I can't think of any instance where bones "un-fuse" over an animals life.

1. What evidence do we have that cave lions and American lions lacked manes?

2. What's the status of Geosternbergia? I know Mark Witton suggested it was just a species of Pteranodon but I'm not 100% sure.

1. From what I can tell, it's because cave art in France shows cave lions with only a small ruff of fur, not the full mane of the modern African Lion. It is also believed that manes evolved in African Lions after the dispersal of lions to North America.

2. I've read Witton's post on Pteranodon, and I find it pretty convincing, but for now they are still considered distinct. For that to change someone will have to do a formal study and get it peer reviewed and published.

What was the purpose of the crests seen on macronian sauropods

tigris115 wrote:

What was the purpose of the crests seen on macronian sauropods

Those were mainly to hold the nostrils so it won't have problems eating. They also might have served as sexual displays, at least for the males, but that's unlikely.

1. What was the lifestyle of ornithomimids like Gallimimus? I've heard everything from dabbling like ducks to omnivores

2.What was the cause of the decrease in biodiversity from the Campanian to the Maastrichtian?

tigris115 wrote:

which one was the male or female. I need to know because when I send the models to be skinned, I want muh dimporphism

If they're anything like Syntarsus & T.rex (See the following quotes), probably gracile & robust, respectively.

Quoting Adler ( http://www.amazon.com/Herpetology-Current-Research-Amphibians-Reptiles/dp/0916984273 ):

Quote :

It is also worthy to note that Syntarsus seems to be a dimorphic species with both gracile and massive specimens at the same individual age (as assessed by skeletochronol- ogy). Since only the robust individuals show large perimedullar erosion cavities in their long bones, they are tentatively interpreted as females, as calcium is removed from the bones to allow for eggshell calcification (Chinsamy 1988, 1990).

Quoting Larson ( http://www.amazon.com/Tyrannosaurus-Tyrant-King-Life-Past/dp/0253350875 ):

Quote :

By use of morphometric analysis, gracile and robust morphs are confirmed to be present within the clade Tyrannosaurus rex. Extant phyloge- netic bracketing (comparison with living crocodiles and birds) leads us to conclude that the existence of these 2 morphs most parsimoniously repre- sents sexual dimorphism. The discovery of medullary bone within the medullary cavity of a robust specimen of T. rex established MOR 1125 as female (Schweitzer et al. 2005), and therefore all other robust T. rex specimens are, in all probability, also female.

tigris115 wrote:

1. What was the lifestyle of ornithomimids like Gallimimus? I've heard everything from dabbling like ducks to omnivores

2.What was the cause of the decrease in biodiversity from the Campanian to the Maastrichtian?

1. Ornithomimids were mostly herbivorous, but from what we know, many did have to ability to eat some small fish, shrimp, large insects, and small mammals.

2. I heard that climate change was a factor, but considering how it changed multiple times, it doesn't seem like it was the main cause, at least in general.

tigris115 wrote:

1. What was the lifestyle of ornithomimids like Gallimimus? I've heard everything from dabbling like ducks to omnivores

See "ORNITHOMIMOSAURIA": https://www.geol.umd.edu/~tholtz/G104/lectures/104coelur.html

tigris115 wrote:

2.What was the cause of the decrease in biodiversity from the Campanian to the Maastrichtian?

See "What does the dinosaur record show?": https://www.geol.umd.edu/~tholtz/G104/lectures/104extinct.html

How are these thagomizers

It might be the angle of the photo, but they look a little flat rather than conical. I'd also consider bringing them up the tail a little bit closer to the body. Not a whole lot, but the tail should have a tip just a wee bit longer.

I remember reading on 'Love In The Time Of Chasmosaurs' that dinosaurs may have settled disputes via wrestling matches like Komodo Dragons do. I can see the iguanadonts, carnosaurs, and most spinosaurs doing this, but what about hadrosaurs and Spinosaurus itself? Were the arms of hadrosaurs strong enough for that kind of power? Because I've always seen their arms as not having the muscle mass of Iguanodon. And Spinosaurus, we don't know how bipedal it was, but one would think it would still be capable of physically fighting.

Did Embolotherium really exhibit sexual dimorphism as seen in Walking with Beasts?

Rhedo, I'd imagine that just about any dinosaurs might have gotten into some tussles with other members of their species. I think the mechanics of their limbs may have been more influential than their strength. For example, arm grappling in hadrosaurs would probably be less likely than say flank ramming.

Tigris: From what I can tell, it did not. Other kinds of Brontotheres do demonstrate it, but all Embolotherium specimens we have show large rams.

I remember reading about the modified version of the head-butting theory where boneheads did use their heads as battering rams, but only for side-on attacks. Were their bodies built strongly enough for that kind of punishment?

There are a lot of factors that go into that. How fast they were running, how strong their ribs were etc. I wouldn't put it past them, because animals are surprisingly resilient. I imagine they were doing a lot of things with those heads of theirs, but I think it is most likely that they were butting heads.

Why were there so many medium to big predators in Mid Cretaceous North Africa? I know that they were many plat eaters, but with so many predators, including Sarcosuchus, it seems like MC North Africa was basically the Wild West of the Mesozoic.

Rhedosaurus wrote:

I remember reading about the modified version of the head-butting theory where boneheads did use their heads as battering rams, but only for side-on attacks. Were their bodies built strongly enough for that kind of punishment?

Hope this helps: http://phenomena.nationalgeographic.com/2013/07/19/butting-heads-over-skull-injuries-and-dinosaur-head-butts/

Rhedosaurus wrote:

Why were their so many medium to big predators in Mid Cretaceous North Africa?

B/c that was normal (See the highlighted paragraph: https://books.google.com/books?id=YuC0fRUwnUgC&pg=PA126&dq=%22did+tyrannosaurids+have+a%22&hl=en&sa=X&ved=0ahUKEwi_9rXvzLXRAhVGNiYKHd1VB3wQ6AEIHjAA#v=onepage&q=%22did%20tyrannosaurids%20have%20a%22&f=false ).

Paleoman wrote:

Rhedo, I'd imagine that just about any dinosaurs might have gotten into some tussles with other members of their species. I think the mechanics of their limbs may have been more influential than their strength. For example, arm grappling in hadrosaurs would probably be less likely than say flank ramming.

Tigris: From what I can tell, it did not. Other kinds of Brontotheres do demonstrate it, but all Embolotherium specimens we have show large rams.

So then where did they get the idea of the males having elaborate shields and the females having stout clubs? And are there any good references of dimprohism in Megacerops?

I would imagine that they wanted to do an episode centered on Mongolia and Embolotherium happened to be the brontothere that lived there. Because other varieties of brontothere are dimorphic, they wanted theirs to be as well.

The old Field Museum statues are probably one of the best references. They show a Megacerops family, and are now at the South Dakota School of Mines and Technology.

Spoiler:

Did Dimetrodon and Edahrosaurus lack earholes?

I remember reading that Triceratops skulls are so commonly found, that they are considered fossils in their own right. With that being said, how many specimens, including the skulls, have been found?

Can someone give me the tl;dr on Trike and Toro? I've heard of young Torosaurus remains being found.

Is there concrete evidence of any Triassic dinosaur species having feathers or protofeathers?

What dinosaur species appear to have gone into extinction because of Triassic-Jurassic mass extinction? Specifically because of it's effects or side effects. As in, strictly during this boundary timeframe or very shortly before/after it?

What single dinosaur species in the fossil record appears to have lived/survived for the longest period in earth history, more or less unchanged?

What Permian land species (or genus) survived not only through Triassic but into the Jurassic as well?

Rhedosaurus wrote:

I remember reading on 'Love In The Time Of Chasmosaurs' that dinosaurs may have settled disputes via wrestling matches like Komodo Dragons do. I can see the iguanadonts, carnosaurs, and most spinosaurs doing this, but what about hadrosaurs and Spinosaurus itself? Were the arms of hadrosaurs strong enough for that kind of power? Because I've always seen their arms as not having the muscle mass of Iguanodon. And Spinosaurus, we don't know how bipedal it was, but one would think it would still be capable of physically fighting.

In reference to hadrosaurs, the following is the best I can do. In reference to Spino, probably completely bipedal: http://paleoguy.deviantart.com/journal/Here-We-Go-Again-The-Spinosaurus-debate-rages-on-582989674

See the highlighted paragraph: https://books.google.com/books?id=rY0ZCgAAQBAJ&pg=PA16&dq=%22fractures+in+prosaurolophus%22&hl=en&sa=X&ved=0ahUKEwjhhIq69NHRAhUGSiYKHVJdBMIQ6AEIHDAA#v=onepage&q=%22fractures%20in%20prosaurolophus%22&f=false

See 18:00-19:30: