|Concavenator corcovatus life restoration by Christopher DiPiazza. If it is ever proven that this dinosaur actually had arm quills I can easily add them to the painting.|
Another interesting feature about the skeleton of Concavenator is that its arm bones possess small bumps on them similar to those found on other dinosaurs like Velociraptor and birds. We know that on modern birds these structures serve as attachment sites for the large wing feathers. On birds and some other dinosaurs we call these attachment sites quill knobs (I have written about these before). Some believe that, although its not that closely related to the dinosaurs that we know for sure had feathers, Concavenator would have had feathers or at least quill structures coming out of its arms. Paleontologist, Darren Naish noted on his website, however, that the structures on the arms of Concavenator are different from those on Velociraptor and birds in that their spacing is not uniform. They are also not on the part of the bone where feathers would typically grow from. Because of these features it is also possible that these knob-like structures were merely for muscle attachment.
There is also much debate over what Concavenator's shark fin hump was for. Some say it was for thermo-regulation (helping the animal's body heat up or cool off when needed) while others think it could have been for species recognition. I personally don't agree with either of these ideas and am a fan of the sexual display idea myself. In my experience working with animals I have learned that if something on an animal looks unusual, chances are its to impress a potential mate.
This week's dinosaur was made possible thanks to a request. As always feel free to request an animal in the comments below or on our facebook page!
Naish, D. (2010). Concavenator: an incredible allosauroid with a weird sail (or hump)... and proto-feathers?. Tetrapod Zoology, September 9, 2010.
Ortega F., Escaso, F. and Sanz, J.L. (2010). "A bizarre, humped Carcharodontosauria (Theropoda) from the Lower Cretaceous of Spain." Nature, 467: 203-206. doi:10.1038/nature09181 PMID 20829793