Finally, some science!
A couple of months ago, a bizaare creature was uncovered in Romania, the Late-Cretaceous dromeosaur
Balaur bondoc ("stocky dragon" in Romanian). Like several other finds from Late Cretaceous Romania, it was an island animal, and as such, had the potential to be very strange. It did not disappoint.
As pictured to the left (by the paleoartist E. Willoughby),
B. bondoc is a unique beastie. While its 2-fingered hands and backward-facing hip are strange enough, what truly sets Balaur apart from its dromeaosaur relatives is the presence of 2 sickle claws on each foot, instead of just 1. The extra pair of claws seems to stem from the raptor's 1st toe, which is normally used for nothing in
Balaur bondoc's relatives on the mainland. It's believed that the creature acted like "more of a kick boxer than a sprinter", using those nasty talons to leave gashes in their prey. As for the odd hip arrangement and the somewhat atrophied hands, well, it's an island animal. It's bound to have weird features like that.
But is that the only reason, though? Is this combination of curious features simply the result of island speciation? Granted, island speciation could very well be the only culprit. After all, creatures that have been isolated on islands tend to be infinitely stranger than those on the mainland (case in point: Birds of Paradise). But, recently, there has been an (unofficial) theory going around linking this creature to another maniraptoran oddball: Therizinosaurs.
Therizinosaurs are strange things. They are members of the order Maniraptora, just like deinonychosaurs (including Balaur bondoc), oviraptors, and tyrannosaurs. However, they deviate from the traditional maniraptoran bauplan in several ways, all thanks to their unconventionally herbivorous lifestyle. To accomodate its enormous herbivore's gut, the therizinosaur's hips swing backward, as in ornithoschian dinosaurs. To deal with the resulting weight gain, its 1st toe tends to be used in aid of walking, particularly in the larger species. On top of all of this, these bizarre creatures possess enormous claws, beaks at the end of their snouts, and herbivore-style cheek teeth. All of these advancements, while very strange and very unlike its kind, help the therizinosaur in its purely (or mostly-pure, possibly) herbivorous lifestyle.
Could
Balaur bondoc have been following a similar route in its evolutionary deviance from its family's standard bodyplan? It's a pretty controversial-sounding theory, and doesn't seem to be supported by much evidence at first glance. In fact, from what I can gather, it's only been mentioned on a few paleontology blogs. However, despite its nascence, the concept of
B. bondoc being the Mesozoic equivalent to the dodo bird does hold some physical evidence, if a close look can be taken on a few key features.
The first and most important feature of scrutiny is Balaur's hip. As said before, it swings backwards like a bird's hip bone, unlike those of most other sauraschians, which swing forward like a lizard's hip bone. In fact, out of the entire natural history of dinosaurs, this only happened 3 other times to 3 other groups; the ornithoschians, the therizinosaurs, and the birds. All 3 of these groups did so due to their herbivorous or partially-herbivorous diet; swinging back the hips allowed them to grow large guts to digest plant material. Since
Balaur bondoc is also a dinosaur, it may follow suit that the hips were swung back for the same or a similar purpose. Also of note is
Balaur bondoc's 2-clawed hands. This reduction would clearly indicate that there was a disuse of the hands in the raptor's lifestyle. Since a raptor's hands are integral to its killing process (foot claws slice through animal, hand claws grab on tight), a reduction in these natural-born tools would seem to communicate that that lifestyle wasn't being implemented at a frequency that would warrant the fingers to remain present and functional. These are all subtle differences, however, that could simply be attributed to the "kick-boxer" lifestyle the creature is postulated to have led.
But even
Balaur bondoc's signature trait-the double killing claw- could betray its herbivorous/omnivorous lifestyle. Take a close look at that extended 1st toe, which at the moment is considered the creature's 2nd killing implement. The toe claw itself is somewhat small, but it's actually blunt in comparison with
Balaur bondoc's major killing implement. In fact, said toe claw seems much more in line with
B. bondoc's "regular" nails in terms of sharpness or ability to hook onto or into surfaces as the animal's weaponized digit does. Thus, it could be argued that, maybe, that extra upraised digit wasn't used so much for attack or defense as it might have been used for support.
To take all of this down a notch, there is a lot of room for error in the theory of Balaur's non-carnivory. For one thing, we are missing the most crucial evidence: the skull. Balaur bondoc came without a skull, so what that looked like, and what the dentition looked like, can only be guessed at. The skull could basically make or break the image of an herbivorous dromeosaur; if it were an herbivorous dinosaur, the skull will come back with rows of conical teeth, for slicing up vegetation, but if the skull comes back with rows of razor-sharp fangs, Balaur bondoc's place as a simple 4-clawed carnivore is cemented. Not to mention, this theory has not yet gained scope beyond a few paleontology blogs (including this one).
That is not to say, though, that this theory should be rejected or scoffed. Nay, the theory that Balaur bondoc was the dromeosaurian answer to the therizinosaur should be spread. A theory is as strong as the facts supporting it, but unless the idea is spread, any other concept other than this might never permeate the scientific world at large until much later, when the complete skeleton is actually discovered (and if the skull really does correlate to an herbivorous diet). Most likely, if that ever happens, it'd be considered a discovery that "shatters our conception of the evolution of dinosaurs", or something like that. Of course, those who read it first here would know the real story.
...
As will be tradition here, I give credit where credit is due, as this theory certainly did not originate with me.
Here's where I found it first, at DinoGoss:
http://dinogoss.blogspot.com/2010/09/balaur-bondoc-dodo-raptor.html
And here's a more in-depth look at the idea than mine, from Jurassic Albatross:
http://wwwmidgetonfire.blogspot.com/2010/09/above-my-own-pencil-reconstruction-of.html
And P.S.:
Yet another preview image for an upcoming piece. Until next time, eat your greens.
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