Hognose venom "debate" over. - Page 6

BarelyBreathing · 05-29-12, 10:26 PM

Basically, I'm asking why you think the venom delivery system is so far into the mouth instead of up front?

jaleely · 05-29-12, 10:27 PM

Hmm. So what IS the difference?
I thought hoggies didn't have the hollow teeth/or the crevices to properly inject venom.

Basically though, they are venomous, they have the glads, they have just not evolved the most effective way to inject it. So, it does secrete out when they bite...and get into the wound. Hence the reaction.
But, it has nothing to do with the saliva...it just perhaps flows with the saliva into the wound...that is the distinction, correct?

Okay, so the rear fangs are shaped that way to work the venom in...through...moving? Or because they are long, it's on the fangs and gets kind of injected? It just seeps in because there is an open wound?

It's not like none of this is making sense...it's just trying to word it in a way that facilitates the whole picture for everyone.
This is exactly why so many people are confused...because it seems like it's all part of the same thing, just slightly more pinpointed in actual process. Does that make sense?

I'm not trying to be frustrating, I'm actually trying to find the perfect wording so we can clear up any confusion : )

red ink · 05-29-12, 10:48 PM

Quote:

Originally Posted by BarelyBreathing

No, I get that. That isn't what I'm asking. I'm asking why they evolved (do you think) to have a less effective means of envenomating their prey than other venomous species?

Actually I think they have an effective way on envenomating their prey due to the lack of toxicity in their venom.

Unlike viperidaes and elapidaes which have higher toxicity in their venom, the grab and hold method of colubridaes work well (for them) in ensuring venom delivery in the epidermis punctures....

Compensation for the lack of venom toxicity, grab and hold....

Assumptions on my part obviously and void of any scientific data.

BarelyBreathing · 05-29-12, 10:50 PM

Quote:

Originally Posted by red ink

Actually I think they have an effective way on envenomating their prey due to the lack of toxicity in their venom.

Unlike viperidaes and elapidaes which have higher toxicity in their venom, the grab and hold method of colubridaes work well (for them) in ensuring venom delivery in the epidermis punctures....

Compensation for the lack of venom toxicity, grab and hold....

Assumptions on my part obviously and void of any scientific data.

Yeah, okay. I can see that.

Any other thoughts?

Gregg M · 05-29-12, 10:52 PM

Quote:

Originally Posted by BarelyBreathing

Basically, I'm asking why you think the venom delivery system is so far into the mouth instead of up front?

Why would be just a guess on my part, but I personally feel that it has a lot to do with the type of prey it "specializes" in. I can not imagine toads, frogs, neonatal rodents and small lizards would give up too much of a fight. Also, the rear fangs are not set that far back into the mouth. The term "rear fanged" is a bit misleading. The fangs are actually situated right below the eye. The fangs are easily sunk into flesh without actually having to swallow and most colubids get them in with a single strike.

The delivery system in hogs may not be effective on us but it seems to be quite effective on the small prey they consume.

BarelyBreathing · 05-29-12, 10:58 PM

Quote:

Originally Posted by Gregg M

Why would be just a guess on my part, but I personally feel that it has a lot to do with the type of prey it "specializes" in. I can not imagine toads, frogs, neonatal rodents and small lizards would give up too much of a fight. Also, the rear fangs are not set that far back into the mouth. The term "rear fanged" is a bit misleading. The fangs are actually situated right below the eye. The fangs are easily sunk into flesh without actually having to swallow and most colubids get them in with a single strike.

The delivery system in hogs may not be effective on us but it seems to be quite effective on the small prey they consume.

Looking at a side view, they appear further back, but I guess I've just been using the front of the mouth as a comparison rather than the whole skull.

Gregg M · 05-29-12, 11:02 PM

Quote:

Originally Posted by jaleely

Hmm. So what IS the difference?
I thought hoggies didn't have the hollow teeth/or the crevices to properly inject venom.

Basically though, they are venomous, they have the glads, they have just not evolved the most effective way to inject it. So, it does secrete out when they bite...and get into the wound. Hence the reaction.
But, it has nothing to do with the saliva...it just perhaps flows with the saliva into the wound...that is the distinction, correct?

Okay, so the rear fangs are shaped that way to work the venom in...through...moving? Or because they are long, it's on the fangs and gets kind of injected? It just seeps in because there is an open wound?

It's not like none of this is making sense...it's just trying to word it in a way that facilitates the whole picture for everyone.
This is exactly why so many people are confused...because it seems like it's all part of the same thing, just slightly more pinpointed in actual process. Does that make sense?

I'm not trying to be frustrating, I'm actually trying to find the perfect wording so we can clear up any confusion : )

I really like the fact that you are asking these questions and trying to get a deep understanding. No need to explain yourself at all.

The rear fang puctures is where the venom will enter. The Duvernoy's secretion does not need the saliva in order to flow. Basically, in hognose snakes, once the fangs sink, the glands are stimulated and the venom will start to flow. Just because there are not groved, it does not mean the venom will not flow down the fang. It just wont be as efficient at being channeled into the wound. As you have seen first hand (pun totally intended LOL) not as efficient does not mean not efficient.

Gregg M · 05-29-12, 11:10 PM

Quote:

Originally Posted by BarelyBreathing

Looking at a side view, they appear further back, but I guess I've just been using the front of the mouth as a comparison rather than the whole skull.

Here is an awful pic I took but you can see how close to the front the fangs really are.

bladeblaster · 05-30-12, 01:27 AM

haven't read everything since my last post, but agree with what Gregg has said about the term 'rear fanged' very misleading term, and should only really taken in context when comparing to 'front fanged' vipers and such.

The fangs of 'rear' fanged snakes are a lot further forward in the mouth than most imagine, and easily engaged into prey as Greggs photo shows.

BarelyBreathing · 05-30-12, 10:03 AM

I guess I never realized that. I have a hognose, but I've never looked too closely into it. I'm allergic to bees, spiders, and scorpions, and I've always thought that people who have those allergies have a higher reaction to snake venom. Is this true? I don't care to test it, that's for sure.

Gregg M · 05-30-12, 03:59 PM

Quote:

Originally Posted by BarelyBreathing

I'm allergic to bees, spiders, and scorpions, and I've always thought that people who have those allergies have a higher reaction to snake venom. Is this true? I don't care to test it, that's for sure.

Being allergic to bees, spiders, and scorpions does not mean you will be allergic to snake venom. The venoms compositions are totally different. In order for you to have an allergy to something, you would need to be exposed to it first. First time stings or bites will not yield an allergic reaction. However, as I mentioned earlier, you can build an allergy after initial exposure. It could happen at the second sting or bite or after the 50th sting or bite.

BarelyBreathing · 05-30-12, 10:03 PM

Yeah, I'm aware of how allergies work. I was just asking if it means that there is a higher possibility of having an intolerance in comparison to those who don't have those allergies.

Gregg M · 05-31-12, 06:24 AM

Quote:

Originally Posted by BarelyBreathing

Yeah, I'm aware of how allergies work. I was just asking if it means that there is a higher possibility of having an intolerance in comparison to those who don't have those allergies.

No, someone allergic to bee stings would not be more likely to have an "intolerance" than someone who is not because the substances are not the same. Its like saying if someone is allergic to milk, they may have an intolerance to water.

Will0W783 · 05-31-12, 07:23 AM

This thread has become quite fascinating- I really enjoy the debates and discussion over the evolution of the venom. I think that rear-fanged colubridae evolved slightly before the elapidae and viperidae, and since their system was effective enough to overcome their prey it didn't need to evolve more. Elapids and vipers needed to overcome larger prey and warm-blooded mammals of greater size so they needed to evolve higher toxicity and more efficient fangs....I don't have much evidence of this, but when looking at the phylogenetic trees of reptilians, it would appear that the toxicity and efficiency of venom delivery improved as the animals progressed down the evolutionary paths. Most rear-fanged colubrids feed primarily on toads/frogs, lizards, and very small mammals, whereas a lot of the elapidae and viperidae must overcome their prey rapidly and feed on birds, larger mammals and other snakes. A hognose can bite and hold onto a toad while its venom works, but a viper in a tree can't wait for venom to take several minutes while it is trying to catch a bird. It needs that venom to be rapid and effective so its prey can't fly away or run away. There's limited mobility in tree tops so it must be a rapid kill.This is how I've always seen it...correct me if I'm wrong.

Will0W783 · 05-31-12, 07:27 AM

Gregg and infernalis, I've met Viperkeeper at the Hamburg, PA reptile shows...he's extremely knowledgeable about his venomous snakes and is a genuinely nice man. I watch all his YouTube videos and really learn a lot from him. Once in a while, one of his videos will show him being a bit closer to the snakes than I would think safe, and I get nervous when I see stuff on the internet that others might copy and get injured doing, but he does clearly display disclaimers not to try what he does. He knows his animals really well, and as a fellow venomous keeper, I can attest that there are snakes I am more relaxed around than others....for example, I know that I can get away with much more cage maintenance and interaction with my Wagler's vipers than I can with, say, the cobra. Shelby must be lock-boxed for EVERYTHING...whereas the Wags can be left alone while water bowls are changed and the cage is drained. It's a matter of learning your animals, but I do think that when things are posted online for everyone to see, you have to be really careful what you show.