The Pachycephalosaur Thread

Adam Khor

It seems that pachycephalosaurs have very strange bony structures on their tails (previously misidentified as gastralia), that are not found in any other tetrapod (although they are similar to structures seen in some fish!). The function of this "tail-basket" remains unknown, but the paper suggests that it may have helped the pachycephalosaur to attain a tripodal stance (!) probably during fighting (!!).
I personally wonder now if these creatures would be able to stand in their tails alone, like kangaroos, and maybe use their feet as well as their head to fight? Or even, mostly the feet? Has anyone ever cared to study the feet of pachycephalosaurs?
Or there may be another explanation for the tail-basket... what do you think?
Very interesting stuff.

http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030212

Oh, and just because it's cool and looks like a pachycephalosaur, here's a rhinoceros iguana:

Galvasean

Ah, I remember seeing some very old restorations of pachecephalosaurs with club tails. This is far more interesting IMO.

Adam Khor

As if the reinforced neck vertebrae (and the enormously thick skull, of course) weren´t enough proof, here's a study about a specimen of Pachycephalosaurus that seems to have evidence of injury (followed by infection) that matches what one would expect if the animal fought by headbutting.

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0036227

Galvasean

Yay!!!

https://www.youtube.com/watch?v=8NaBHCuxqhA

Adam Khor

Stegoceras apparently did have ornaments on its head dome as a juvenile that changed/dissappeared as it grew larger.

I guess it gives some credibility to the idea that Dracorex/Stygimoloch could possibly be juvenile Pachycephalosaurus.

http://blogs.smithsonianmag.com/dinosaur/2012/08/how-domed-dinosaurs-grew-up/

Galvasean

Jack Horner was right?! :eek:

Adam Khor

Galvasean wrote: »

Jack Horner was right?! :eek:

}

He can´t! There must be another explanation!!

Capt'n Midnight

Adam Khor wrote: »

}

He can´t! There must be another explanation!!

law of large numbers / stopped clock accuracy perhaps ?

Adam Khor

Lo and behold, paleontologists have discovered (again!) that Pachycephalosaurs fought by head butting.

http://www.msnbc.msn.com/id/49464238/ns/technology_and_science-science/#.UICLlmf4Vac

Seriously, how many times do they have to re-discover this?

Galvasean

In other dino news, T. rex used its mouth to bite.

Capt'n Midnight

We know pachycephalosaurus took nothing for the headaches.

because nothing works faster than anadin :pac:




And yes that joke is old enough to be here.

Humbert Humbert

I don't get it?

Capt'n Midnight

Here is an old anadin ad 1/10d and 3/8d
https://secure.flickr.com/photos/32705854@N04/3870336524/

Adam Khor

Cute little guy, could probably break your knees:

http://www.sci-news.com/paleontology/article01059.html

Galvasean

Hmm, I wonder what a 'proto-pachycephalosaur' would look like...

Adam Khor

Galvasean wrote: »

Hmm, I wonder what a 'proto-pachycephalosaur' would look like...

I'm thinking maybe a lot like a heterodontosaur

Adam Khor

Pachycephalosaurus was born spikey

http://phenomena.nationalgeographic.com/2016/03/30/paleontologists-uncover-the-tiniest-bonehead/

Adam Khor

Pachycephalosaurus is usually thought to have been a vegetarian but a new skull with well preserved teeth shows that those in the front of the jaws were sharp and serrated, practically the same as those of carnivorous theropods. The skull is from a juvenile (a "Dracorex" type), so it is not clear whether this was a trait of the juveniles only (in which case this would be another case of a dinosaur switching from carnivore/omnivore to vegetarian as it aged) or if it was a normal trait of the species/genus.

https://www.nationalgeographic.com/science/2018/10/news-vegetarian-dinosaur-ate-meat-pachycephalosaurus-paleontology/

Adam Khor

New study on cerapodan phylogeny finds heterodontosaurs to be basal pachycephalosaurs:

https://www.tandfonline.com/doi/full/10.1080/08912963.2020.1793979

Not particularly surprising considering juvenile pachycephalosaurs seemingly had long, sharp teeth resembling the heterodontosaur's tusks- apparently these creatures made it all the way to the latest Cretaceous!