Spinosaurus had a rather unusual tail

[Haravex]

https://www.nature.com/articles/s41586-020-2190-3

 

For your reading pleasure.

[Haravex]

Adding some of the pictures as the paper is paywalled.

41586_2020_2190_Fig4_ESM.webp

41586_2020_2190_Fig5_ESM.webp

41586_2020_2190_Fig6_ESM.webp

41586_2020_2190_Fig7_ESM.webp

[Troodon]

National Geo article

 

https://www.nationalgeographic.com/science/2020/04/spinosaurus-graphic-reconstructing-gigantic-aquatic-predator/

 

[Haravex]

Thank you troodon currently feeling a little delicate this afternoon and was having issues with adding the photographs.

[LordTrilobite]

Holy carp, what.

[Abstraktum]

Beautiful discovery. The shape of Spinosaurus is beeing shifted again. The more we know the more aquatic Spinosaurus gets. Well I guess thats why two Apex Predators like Spino and Carch could live in the same environment 

[Troodon]

Interesting blog from one of my favorite theropod bloggers

 

http://theropoda.blogspot.com/2020/04/spinosaurus-revolution-extended-edition.html

[ziggycardon]

Wow that is a cool discovery! Thank you for sharing!  

 

[Troodon]

57 minutes ago, Abstraktum said:

Beautiful discovery. The shape of Spinosaurus is beeing shifted again. The more we know the more aquatic Spinosaurus gets. Well I guess thats why two Apex Predators like Spino and Carch could live in the same environment 

It also continues to support the notion that a key food supply for this environment was marine why the inbalance with herbivores 

[Macrophyseter]

Very interesting fold out for the Spinosaurus. For some reason, I've always thought it be satisfying if there were indeed aquatic (or possibly marine) dinosaurs in the fossil record in the midst of a diversity of aquatic non-dinos, and it looks like Spinosaurus might be a good candidate for that. 

 

I don't have access to the paper, and I am a bit out of the blue. How did Ibrahim et al. conclude that the associated tail, which according to the skeletal posted by Troodon did not come with other or with few associated fossils from other parts, is of the Spinosaurus genera and not of another (possibly indeterminable) large spinosaurid? Are there any Spinosaurus-exclusive bone features that were found in the tail?

[Troodon]

The supplementary info is not paywalled, at end of the paper 

Here is a video on some caudals

https://static-content.springer.com/esm/art%3A10.1038%2Fs41586-020-2190-3/MediaObjects/41586_2020_2190_MOESM6_ESM.mp4

[piranha]

Someone needs to attach the sound file of theme music from "Jaws" to this animation

[Troodon]

5 minutes ago, Macrophyseter said:

Very interesting fold out for the Spinosaurus. For some reason, I've always thought it be satisfying if there were indeed aquatic (or possibly marine) dinosaurs in the fossil record in the midst of a diversity of aquatic non-dinos, and it looks like Spinosaurus might be a good candidate for that. 

 

I don't have access to the paper, and I am a bit out of the blue. How did Ibrahim et al. conclude that the associated tail, which according to the skeletal posted by Troodon did not come with other or with few associated fossils from other parts, is of the Spinosaurus genera and not of another (possibly indeterminable) large spinosaurid? Are there any Spinosaurus-exclusive bone features that were found in the tail?

Checkout the blog I posted

[Macrophyseter]

5 minutes ago, Troodon said:

Checkout the blog 

My bad! 

 

I understand now, thanks!

[LordTrilobite]

https://www.sciencenews.org/article/spinosaurus-dinosaur-fossil-tail-aquatic-swimmer

Another article.

 

It also includes a link to a view only version of the publication.

[Haravex]

It's also awesome that we can now update our paleoart.

 

 

[gms]

And the official video:

 

 

[Jaimin013]

Wow this is absolutely incredible! Very interesting how it indicates that the Spinosaurus was a far better swimmer than we thought and probably spent large amounts of time fully submerged. I'm even more curious now as to how it walked when it was on land

[dinosaur man]

Wow!  Just looks more crocodilian as more discoveries are made! 

[Tidgy's Dad]

Morocco's own take on the matter :

https://www.moroccoworldnews.com/2020/04/301155/fossil-discovery-in-morocco-reveals-ancient-african-river-monster/

[LordTrilobite]

In that video they showed scanning of some of the vertebrae. The scans have been posted on Sketchfab. These models are really informative. It should be quite doable to properly ID spinosaur caudal verts and their position now. Even if they are isolated.

https://sketchfab.com/gabbro/collections/spinosaurus-aegyptiacus-neotype

 

I'll link some of them here for easy viewing.

 

[Abstraktum]

Some different thoughts regarding the new tail.

 

https://www.nytimes.com/2020/04/29/science/spinosaurus-dinosaur-tail-swimming.html?fbclid=IwAR05PUHT9qzQDpsrU8I1PSh8cZk8xwmOxQURKXzzrNGtdnBIhTqVPeYPdTU

 

 

Quote

Donald M. Henderson, curator of dinosaurs at the Royal Tyrrell Museum in Alberta, Canada, said it was likely that Spinosaurus lived at the edges of water and ate fish — the grizzly bear lifestyle — but he remained doubtful that Spinosaurus was much of a swimmer.

 

“No way,” he said. “My first thing is, they haven’t actually demonstrated that this tail could produce enough force to propel a six-and-a-half-ton body through the water.”

 

What the researchers should have done, Dr. Henderson said, is taken the experimental results and scaled them to the full size of the dinosaur.

 

He said the researchers should have also considered whether Spinosaurus could have enough muscles to move such a long, heavy tail, and how much drag the giant sail on its back — its most characteristic feature — would have produced.

 

“You try dragging a big billboard through the water,” Dr. Henderson said. “It doesn’t work.”

He said the shape of Spinosaurus also appeared too buoyant and prone to tipping over, unlike the wider bodies of crocodiles. ““They haven’t properly addressed this capsizing problem,” Dr. Henderson said.

 

[Troodon]

1 hour ago, Abstraktum said:

Some different thoughts regarding the new tail.

 

https://www.nytimes.com/2020/04/29/science/spinosaurus-dinosaur-tail-swimming.html?fbclid=IwAR05PUHT9qzQDpsrU8I1PSh8cZk8xwmOxQURKXzzrNGtdnBIhTqVPeYPdTU

 

 

 

I read this, not surprised following his buoyancy Spino paper of 2018 and it will be interesting to see what Hone and Holtz say following their 2019 paper that also rebutted Arden et al. 2018 paper that indicated it was semi-aquatic.  Their comment was "some spinosaurs may have spent extensive time in water, but the data to support this is currently insufficient and other hypotheses for their behaviour also fit the available data."  

 

I think we need to keep an open mind these Theories will continue to evolve  

 

This was tweeted by sauripus 

[Abstraktum]

Can't wait for the 33 Version of Spino

[BobWill]

I didn't read all of the material posted here so this may have been brought up already but if not I wanted to get some feedback on this idea. With all this focus on the tail we shouldn't forget the original speculation on the reason for the sail. Different ideas were floated but now it seems likely it may have been used more like the keel of a sailboat, for stability. When fully submerged the movement of the tail would have caused some back and forth movement of the body and the sail could have worked to dampen that effect making for a straighter course through the water with less wasted motion. I don't remember if this was one of the original theories or not. Thoughts?