Interesting.
Thank you for the links Kor.
(Pangaea might be most interested in this.
)
You are absolutely right, Saft!
Surprisingly enough, I hadn't heard of this dinosaur until I saw this post. Thank you very much, Kor!
A stocky, island-dwelling dromaeosaur with a reduced third finger and a dewclaw that evolved into a second sickle claw…this is REALLY interesting!
At first when I saw the Wikipedia link, I thought, "Oh, it's just another new generic dromaeosaur that's making the news because it's related to
Velociraptor", then I started reading more and found out just how wrong I was!
I can hardly call myself an expert in dromaeosaur biomechanics, but I'm a little iffy about the statement that because its hands were atrophied, it probably mostly used its feet to attack prey. Only the third claw looks atrophied to me; the others still look pretty well-developed. The extra sickle claw is really strange, though.
I wonder if the double sickle claw would have been more of a hindrance than an asset to attacking prey. There was a show I watched that talked about movie monsters and the guy talked about how the killer shrews from that movie couldn't bite into prey that well with double canines. Well they could, but they wouldn't be able to pull their teeth out; they'd be stuck and it would take more effort to free them. He demonstrated this using knives.
I saw that show too, but I noticed that the guy didn't demonstrate how much easier a single knife could be pulled out compared to a double knife. He didn't pull the single knife out onscreen. Plus, he was demonstrating on a watermelon; I don't know how accurate an analogue that is for the skin and flesh of an animal. And I've seen illustrations of certain predatory therapsids (so-called "mammal-like reptiles")ósuch as
Trochsaurus and
Lycosuchusóthat actually do depict them as having double saber teeth of a sort (though how exactly they used them is anybody's guess).
Obviously
Balaur’s extra sickle claw served some important purpose. Climbing IS a possibility, but why then would it lose one of the claws on its hands, and gain a functional claw on its feet, when the smaller, earlier dromaeosaurs like
Microraptor that were definitely climbers apparently got along just fine with three hand claws and three foot claws, including a single sickle claw? Furthermore, if
Balaur was, as the article suggests, one of the dominant predators in its environment, would it have much reason to climb? I’m still clueless about the reason for its odd claws, but from what the article suggest, it seems to me that it would be more of a ground predator.
I’ve long been interested in island-dwelling animals and how they differ from their mainland cousins. Interestingly, there were several other Mesozoic examples that lived at about the same time and in the same part of the world as
Balaur, including
Magyarosaurus, a miniature sauropod that was only as tall as a horse;
Hatzegopteryx, the largest known pterosaur; and
Tethyshadros, a hadrosaur with toothlike serrations on its beak that was specialized for running (possibly from creatures like
Balaur).
