Southern Super Raptor!

Galvasean

Paul Sereno wrote:

This was a monster raptor that makes the Velociraptor look like kid's play.

Pretty mad looking beastie. Small arms, robust build and a really narrow head. I wonder how it hunted.

http://news.nationalgeographic.com/news/2008/12/081217-new-raptor-missions.html

dlofnep

Just read from your other thread - Very strange looking indeed. the small arms would lead me to believe that he was probably more built and muscular than the similarly sized Utahraptor, which perhaps meant he could have scavanged at times.. Just a hypothesis though.

Galvasean

Indeed. The arms wouldn't be much use at grappling prey as appears to be a common trait among the dromaeosaurs. Also, the famous claw isn't as pronounced as in many other dromaeosaurs, making it a less effective killing tool. The long snout may have been used for burrowing deep into old carcasses.
Again, purely hypothesizing though.

dlofnep

Did it have a retractable claw on the foot? I don't see a mention of it, but the picture suggests it did. Argentina seems to be weird in the sense that the dinosaurs there were extremely large.. Argentinasaurus, Giganotosaurus and now this guy.

Galvasean

Paul Sereno wrote:

At five meters long with a sickle-shaped claw, it was an amazing predator.

So according to him it did have the trademark sickle claw. The image depicts the claw, albeit comparatively small. Perhaps it was a vestigial thing, sort of on the way out as this particular line of dromaeosaur evolved toward a scavenging lifestyle?

Comparitively speaking the southern continents in general had huge dinosaurs during the Cretaceous. Where South America had Argentinosaurus and Giganotosaurus, around the same time Africa had Paralititan, Carcharodontosaurus and Spinosaurus!

dlofnep

True enough.

Galvasean

Also, I forgot to mention that it (Austroraptor cabazai) had small, fairly conical shaped teeth. These could well have been more suited to gnawing on bones rather than slicing flesh. Paul Sereno himself pointed out this attribute, along with having tiny arms when stating that the abelisaur Carnotaurus was most likely a scavenger.
It would seem Carnotaurus and Austroraptor have a lot in common:
- small arms
- small not particularly sharp teeth
- stocky robust build

Weird how Sereno calls Austroraptor an "amazing predator" while to him Carnotasurus is a scavenger.

Carnotaurus:

Austroraptor:


I see similarities.

dlofnep

I agree that there are similarties, but as a raptor - you would assume that he was a quick runner - which is really only beneficial to predators when attacking, rather than scavaging.

For me - I think he was a pick and choose sort of guy. Sort in between evolution from a raptor to a large carnivore, but not there yet. He still had the characteristics of a raptor, with speed and intelligence favouring his attacking of prey - but also, large size, which might allow him to bully off smaller predators from their freshly killed meal.

Not everything is black and white, and when we find fossils - it would be perfectly OK to assume that an animal could be still at an evolving stage from one species to another.

Thoughts?

Galvasean

Certainly. Austroraptor ceratainly appears to be on it's way down the path of scavenger. Of course I don't buy into the concept of any carnivorous dinosaur to be '100% scavenger'.
Since it lived approximately 70MYA (pretty close to the end of the reign of the dinosaurs) we aren't very likely to discover it's decedents and compare them to see if they had evolved more scavenger-like traits. Our best bet to properly study it's evolution would be to look for it's ancestors and see how it compares. Exactly when these traits first appeared in the dromaeosaur lineage is anyone's guess.

One thing it does show is the diversity of the dromaeosaurs as a group. On one end of the spectrum we have this big and bulky Austroraptor, while at the other end we have the tiny and graceful Microraptor gui.

dlofnep

Microraptor.

Galvasean

The skeleton is now on display in Buenos Aires:
http://www.canada.com/technology/science/Giant+meat+eating+raptor+dinosaur+discovered+Argentina/1091014/story.html

Galvasean

'Ol Jack Chance

The size of that thing! It defo makes the velociraptor look like a chicken. I wonder if they hunted in packs...

That kid in the last picture reminds me of the kid at the start of Jurassic Park

dlofnep

Oh gawd, he's awesome!