The case of the venomous dinosaur.

Click me first.

I know a few people, especially laymen, that are going to have a conniption over this. The fact of the matter is that it is relatively unexciting and shouldn't be a shock to anyone.

Dinosaurs are an exceptionally diverse group, especially when one properly includes Aves, as they should, into the mix. They are at least as diverse as mammals, I would think, and mammals don't typically use venom at all. There are few that have or had venom, but it's not a typical thing like it is in Eureptilia, where snakes (obviously), monitors and even bearded dragons have some form of venom. In fact, I wouldn't be surprised to see most Eureptilians with venom of some sort- it would certainly explain the docility of their insect prey shortly after capture.

With such diversity within Dinosauria, it's definitely not a shock that one or probably more dinosaurs developed venom. It makes sense for a relatively diminutive dinosaur such as this to upgrade it's arsenal to create a niche for itself. The question in my mind is whether or not it also used the grooves to channel bacteria to a live animal, in the same way komodo dragons do today, if they hunted larger prey (which is entirely possible depending on the strength of the venom) or if they merely used it to subdue some upstart mammal with something to prove, thereby removing the need for a more robust skull and jaw system. Guess there's not many ways of proving that though. Oh well.

In conclusion, I hope anyone reading this is done with the excitement and awe of being shocked by nature. That boat sailed long ago for me and it should have for you as well.

Update: I was talking to a theropod expert and asked about this paper. He remains a bit skeptical and is very good at what he does, so I'm waiting to get my greasy hands on a pdf of the actual paper for further updates. In the meantime:

"They could be teeth that have slipped out of their sockets. All theropod teeth have grooves in the sides: of the roots" - Dr. Awesome

also

"Except for blood grooves along the serrations. They would make sense exapted for venom delivery, among the "wuss"-type theropods." -Dr. Awesome


"Archosaurs seem to suck at having chemical factories in their mouths, and lepidosaurs are good at it. Are there any lizards with bacteria incorporated into glands? It seems more likely that their salivary glands go crazy, and occasionally start making nasty stuff that natural selection promulgates." -Dr. Awesome

"Well actually, if a komodo dragon doesn't have access to rotting flesh it doesn't gain access to the bacterial bite. Komodos are the only ones I know of that actually harness it effectively, or at all. As far as I know the bacteria just kind of hang around the surfaces of the mouth but it IS facilitated for somehow- I'm not clear on how, but they do seem to have gone evolutionarily out of their way to help the situation." -Mr. Steve

Looks like I'm a jackass, after a short internet search

However, the point about venom in komodos is true, as is the fact that they do have exceptionally filthy mouths. I wouldn't be shocked if that comes into play somehow, as I do think some of the wounds they inflict become gangrenous rather rapidly. Other varanoids are venomous, including the famous Heloderms- but on the other extreme of the squamate family tree, Agamids have been shown to have some type of venom. Sphenodonts, I think, are too basal to be involved in any common ancestry involving venom.

Well, both points are very good, so I must wait for the paper to see...I will update again once I've read it, or have more data, but I'm fairly sure squamates are too far removed from archosauria to really be a fair comparison.