Spinosaurus new look!

[stargatedalek]

If you thicken the back to a hump it could help with buoyancy,  the legs could have been for walking along the bottom,  rather than swimming

[Newt]

I've spent a lot of time in swamps, marshes, and similar environments. The float-and-kick-yourself-along method works OK, but only in a limited range of depths (probably even a smaller range, relative to its size, for Spinosaurus, due to its short and relatively inflexible limbs), and it is characteristic of such environments that the depth is highly variable. It is also an extremely slow way to move, as it does not allow you to use your limb muscles to best effect. Not a problem for a full-grown spinosaur, perhaps, but younger ones would need to be able to put on a burst of speed to get away from the many massive predators in that environment.

A fatty hump would make the animal more bouyant, but only when it was in deep enough water to basically free float. It would need to swim in this situation. It would also have difficulty reaching the surface to breathe when out in such deep water.

It's a perplexing design.

[HD-man]

I think other spinosaurids were like that, but Spinosaurus seems to have evolved to be a mainly aquatic animal.

And also, it's looking like Spinosaurus really is the only true "aquatic dinosaur".

How do you guys figure that? Based on what I've read (Amiot et al. 2010), Spinosaurus was less aquatic than other spinosaurids (which were semi-aquatic, not "mainly" aquatic).

BTW, this reminds of a Norell et al. quote: "The most aquatic dinosaurs that we have evidence for are penguins. Penguins display aquatic modifications, such as flippers and a torpedo-shaped body, and have been seen hundreds of kilometers out to sea. Unlike the ichthyosaurs, however, which fossil evidence indicates gave live birth as whales and dolphins do, penguins must return to land to lay eggs and rear their young" ( http://www.amazon.com/Discovering-Dinosaurs-Evolution-Extinction-Prehistory/dp/0520225015/ref=la_B001H9XFL4_1_3?s=books&ie=UTF8&qid=1408589072&sr=1-3 ).

[Balaur]

Did they take into account the new specimens?

Edit: They were aquatic in the same way that crocodiles are. Its just that the new remains seen to make it difficult for Spinosaurus to walk on land (short legs, large sail, front heavy), and it seems like something from the water.

[Brontozaurus]

Does this mean that the old bright orange Safari Spinosaurus is suddenly the most accurate toy available? It's low-slung(ish) and it has the square sail...

[tyrantqueen]

Does this mean that the old bright orange Safari Spinosaurus is suddenly the most accurate toy available? It's low-slung(ish) and it has the square sail...

This one?



There's an issue with the hands though. It seems to have thumbs, and extra finger...

[Blade-of-the-Moon]

I think he means the Wild Safari one :


Little different..same issue with the hands though. 

[Dinoguy2]

I think he means the Wild Safari one :


Little different..same issue with the hands though.

The sail is better but aside from the sail and legs the Carnegie still blows them all away in terms of accuracy. I wonder if they could slightly re-tool it and re-release without resculpting the whole thing.

[Newt]

Just an odd musing re: the function of Spinosaurus's sail. It has been suggested that this animal fed like a sort of mega-heron. Some modern herons hold their wings spread to cast a shadow on the water, thus reducing glare and improving the bird's ability to see submerged prey. Maybe Spinosaurus used its sail in the same way, standing perpendicular to the sun's rays and hunting in its own shadow.

I don't think this is particularly likely, but it seems at least plausible to me. Thoughts?

[stargatedalek]

It was fairly likely,  in fact it was the assumption I used to go on, but with the new version of its legs its not especially plausible anymore

[Newt]

Why not? Heron-style proportions are not really necessary for heron-style feeding; a heron's legs allow it to get into water deep enough for appropriately-sized prey without wetting its feathers. Spinosaurus may not have had so much concern for getting wet, and the absolute length of its legs was sufficient to get it into water deep enough to contain large prey; the relative length of the legs is immaterial.

[stargatedalek]

Longer legs give it a higher shadow and allow it to surprise prey, it could strike from above unexpectedly if its body was held above the surface, whereas partially submerged it would startle prey as it moved to reach for it, it's still possible,  but I think far less likely than it was

[amargasaurus cazaui]

I think the new look is more in line with what happens if you place a 3-5 ton theropod in deep mud.If the legs were long and reconstructed like they were before, the dinosaur would sink up to its body constantly. However if you could displace the weight over a greater distance and width it would tend to sink less rapidly or deeply. To me that looks like what Sereno is going for .

[Newt]

In my experience, fish are far more suspicious of a vertical than a horizontal body; the same individuals will flee a slowly wading human but closely approach a slowly swimming human. Of course, this could just be because they have been conditioned by experience with (vertical) wading birds, which would be less applicable to the Cretaceous...

In any case, crocodilians seem to have little trouble catching fish - and they're not outswimming them. If crocs can do it, spinos can.

Again, I'm just making a case for the fun of it. I don't really think this is what spinosaur sails were for.  For one thing, it does nothing to explain the low sails in other spinosaurids, which would have been little use for this function.

[Newt]

I think the new look is more in line with what happens if you place a 3-5 ton theropod in deep mud.If the legs were long and reconstructed like they were before, the dinosaur would sink up to its body constantly. However if you could displace the weight over a greater distance and width it would tend to sink less rapidly or deeply. To me that looks like what Sereno is going for .

Are you talking about the way the animal is sitting on its whole foot? That would make sense, but I don't believe Sereno is reconstructing it that way; I think Rey was simply showing the animal in a resting posture. The skeletal reconstruction pictured, if I understand it correctly, incorporates Sereno's new interpretation, and it shows Spinosaurus in a typical digitigrade stance. So the animal would still sink in soft mud - in fact, it would sink worse than a theropod with proportionally larger feet -  it just wouldn't have as far to go before it bottomed out.

Rey's original picture before he modified it: http://luisvrey.wordpress.com/2014/04/29/yet-another-for-the-african-saga/. As far as I can see he only changed the sail (and dropped out the Ouranosaurus herd).

[Yutyrannus]

It seems to me that Spinosaurus was the most specialized of all spinosaurids, the extreme sail and ridiculously short legs seem to indicate that it was doing something very different from other species. I think that most spinosaurids used their sails/spinal ridges/whatever you want to call them mainly for display, but Spinosaurus probably had a different function for it in addition to that, we'll probably never know what though. I myself really think that this implies that Spinosaurus was mainly aquatic (which would make a lot of sense considering it lived in mangrove swamps).

[Newt]

I still don't see how it moved. Nothing about it implies any adaptations for swimming, or for wading on soft substrates. It's a puzzle.

Another thought- could spinosaurus have been a specialist croc hunter? I get the impression the beds its known from are lousy with crocs.

[Yutyrannus]

I still don't see how it moved. Nothing about it implies any adaptations for swimming, or for wading on soft substrates. It's a puzzle.

Another thought- could spinosaurus have been a specialist croc hunter? I get the impression the beds its known from are lousy with crocs.

Hmm...interesting theory. That's actually quite possible.

[amargasaurus cazaui]

Just a few things....dont look at the stylized art, look at the picture of the supposed new mount and how the legs are positioned and the bones aligned. The stature being given would make it far more of a capable mud wader than standing upright with fully extended legs. The legs are bent closer to the ground and paralel with rather than being standing columns to sink straight in.The dinosaur is more bowed forward as well.
   As to the entire croc discussion....Stromer named something like ten new species of crocodilian from the fossils that Spinosaurus was excavated with. Many of these have been proven to be incorrect species, but there was a large amount of crocodilian material found in and around the Spinosaurus remains he worked with.Aside from that Stromer also maintained there was a second and possibly third species of Spinosaurus present in his material. We will never know for sure obviously , but we can be sure there was alot of crocodilian fossil material clearly associated with and around the original fossil.I had mentioned this perviously in another thread as well.

[Yutyrannus]

Also, I was wondering, could Aegyptosaurus be he same animal as Paralititan?