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Defensive Snake Venom? A survey of pain in snakebite patient

PostPosted: Fri Nov 18, 2016 9:31 am
by Mario Schweiger
I share this from facebook. Mario

Wolfgang Wüster:
"Hi All,
My project student Harry Ward-Smith is carrying out a survey on early pain after snakebite. The idea is to test to what extent snake venoms appear to be adapted to a defensive role (which would predict rapid, severe pain to repel predators) rather than solely a foraging one.
If you have suffered any form of envenomed snake bite (viper, elapid, atractaspidid OR colubrid!), we would really appreciate it if you could take a few minutes to complete the survey. And please share widely.
Many thanks!"

pain in snakebite form

Re: Defensive Snake Venom? A survey of pain in snakebite pat

PostPosted: Fri Nov 18, 2016 11:53 am
by Michal Szkudlarek
I will post it on a Polish website for nature enthusiasts. Hope this will help.

Re: Defensive Snake Venom? A survey of pain in snakebite pat

PostPosted: Fri Nov 18, 2016 9:48 pm
by Berislav Horvatic
A KEY PREDICTION for a defensive venom function is that it should cause near-instant severe pain, to repel a predator
before the snake has been killed or injured. If the pain only arose after a delay, the predator will have already killed
the snake making venom useless as a defensive strategy.

As far as I know, a bite by ANY venomous snake does NOT produce any near-instant severe pain (save a spitting cobra),
so... what's the real(istic) point of this study at all?! Please, pardon my impertinence and/or my ignorance...
I've been bitten by several NONvenomous snakes, and it hurts, of course, instantaneously. That's what the venomous
ones try as well - but what else could/should they attempt? But do they count on their venom as well? Evolutionarily,
yes, it might pay in the long run (the predators might "learn" - evolutionarily, written: genetically - to avoid trying),
but at the decisive moment, for an individual snake, no. They certainly don't do it for THAT reason. No individual
animal cares for the farsighted, evolutionary benefits.
If the individual predators who try to meddle with a venomous snake die soon afterwards, and therefore leave no
(or too little) offspring, that might “teach” their SPECIES, give it "an evolutionary lesson”, but certainly not them,
as individuals.
Anything else?

Re: Defensive Snake Venom? A survey of pain in snakebite pat

PostPosted: Sat Nov 19, 2016 4:23 pm
by Ruggero M.
Interesting! Probably not all venomous snake bites are painful at once, but I would say that al least 50% of them become painful rather quickly, in a matter of minutes. Not all the bites, sure, but many of them. You can search Echis bites for instance, and pain is reported in more than 50% of the cases.
The question is: could a horse or a buffalo connect the pain to the snake/bite received few minutes earlier?
Some species I suppose could do that... chimpazees? Horses? Dogs? They are not stupid animals... I think they could connect the two events (snake + pain/swelling) and avoid contacts with the snakes in the future!

Re: Defensive Snake Venom? A survey of pain in snakebite pat

PostPosted: Sat Nov 19, 2016 7:43 pm
by Berislav Horvatic
Ruggero Morimando wrote:Interesting! Probably not all venomous snake bites are painful at once, but I would say that al least 50% of them become painful rather quickly, in a matter of minutes. Not all the bites, sure, but many of them. You can search Echis bites for instance, and pain is reported in more than 50% of the cases.!

In a matter of SECONDS any large predator like us, humans (or a buffalo, or a horse, or a dog...) could smash a snake’s head...
much before it dies itself (or not), and much before the pain due to the VENOM itself starts to work...

The question is: could a horse or a buffalo connect the pain to the snake/bite received few minutes earlier?
Some species I suppose could do that... chimpazees? Horses? Dogs? They are not stupid animals...

I would call you an optimist... Sheep get regularly bitten by V. ammodytes and alike, just ask the shepherds about that.
Dogs as well, just ask the hunters.

I think they could connect the two events (snake + pain/swelling) and avoid contacts with the snakes in the future!

PROVIDED they SURVIVE the envenomation... I would say a black mamba or something like that just doesn't count on THAT
possibility when it bites in defence... and doesn't count on the potency of its venom at all. It just bites, to scare the enemy
away, like any other snake.

After all, the offered questionnaire is meant for PEOPLE, to report their personal experiences, not to chimpanzees, dogs or pigs.

Re: Defensive Snake Venom? A survey of pain in snakebite pat

PostPosted: Sat Nov 19, 2016 9:59 pm
by Ruggero M.
Dear Bero,

I agree with you on the main line: I mean, I think too that venom has an evolution history strictly related to paralizing and also digesting preys, and not as a defence system... but the question is: could the "defence" had played a role (maybe a minor role) in the evolution of venoms in snakes or in some snake species?

That said.

I've read reports about snake bites that are immediately painful: I do not remember which species were involved, where and when, but I'm pretty sure about that.
On the contrary I've a monography about Taipan bites in Australia, with many human bite cases and pain was absolutely absent... I do believe Taipan bites are painless, but it's not true that a human (or a pig or a dog) can crash a Taipan head in a few seconds: a Taipan could deliver 2-3 bites very rapidly and disappear in a fraction of a second, just like many european whipsnakes (viridiflavus, caspius, and so on) have disappeared under our sight in a fraction of a second!

The questionaire is meant for people, you write: but this is obvious. You cannot interwiev a dog or a horse and ask it, if the snake bite was immediately painful or not!

You write that sheep are always bitten by snakes, and dogs too, but this means nothing. Humans always die in motorbike or car accidents, but this fact does not mean humans don't know the risks of driving a car or a motorbike!
This fact would mean more if a dog (or a cow) already bitten by a venomous snake (and having they clearly seen the offending snake!) would ignore in the future the presence of a similarly well seen and exposed snake! But this is almost impossible to prove, considering also the fact that in natural environment dogs or sheep are very often bitten by snakes inside the vegetation, without they know what's happening or without they even see the offending snake!


To summarize: I think almost the same as you, but we could not exclude that, maybe only in some snake species, a painful venomous bite could have played a (probably minor) role in venom evolution, just like it happened in wasps and bees, whose sting is always very painful...

I was only once bitten by a venomous snake: a baby V.aspis managed to put one of its fangs inside one of my fingers. No pain.
I was bitten many times by non venomous snakes, and big colubrid bites can be rather painful (just like being scratched by thorns): but the same bite in a horse, or a wild boar or a big dog would mean almost nothing as regards pain, I suppose... :lol: But, as you correctly said, this is the only reaction small/normally sized snakes (I mean: not huge constrictors) can do...

Another interesting question: snake instinct and "awarness"...
Snakes act and behave by instinct...ok... (I would not say that alien creatures could say the same for us humans.... :lol:)
A Taipan knows nothing about its venom: but it "knows" very well that after a bite it can release the prey and it "knows" very well that it will soon find it dead and ready to be eaten. An Aesculapian snake, on the contrary, "knows" that the prey must be coiled up at once with the body if it has to be eaten... otherwise, prey is lost!
How can we say with certainty that a Taipan "does not instincly know" it has a terrible weapon also on the defence side? :roll:

Re: Defensive Snake Venom? A survey of pain in snakebite pat

PostPosted: Sun Nov 20, 2016 12:24 pm
by Ruggero M.
P.s. And what about the aposematic colours of coral snakes? Painful bites...? I don't think they are immediately painful, but the aposematic colours are a signal of defence... or what else?

Re: Defensive Snake Venom? A survey of pain in snakebite pat

PostPosted: Sun Nov 20, 2016 3:29 pm
by Berislav Horvatic
You write that sheep are always bitten by snakes, and dogs too, but this means nothing. Humans always die in motorbike
or car accidents, but this fact does not mean humans don't know the risks of driving a car or a motorbike!

Humans have had no evolutionary time to become "genetically afraid/wary" of cars and motorbikes, just as e.g. hedgehogs
have not. Snakes have had enough time to be wired-up in our brains (or genes) as dangerous, we don't have to think about it.

How can we say with certainty that a Taipan "does not instincly know" it has a terrible weapon also on the defence side? :roll:

Of course we can’t, but that question belongs to philosophy. A very old question, never really resolved – see David Hume
and the rest... up till the present day.
May I just mention the dry defensive bites, in many venomous species...

Re: Defensive Snake Venom? A survey of pain in snakebite pat

PostPosted: Sun Nov 20, 2016 4:48 pm
by Michal Szkudlarek
Of course we can’t, but that question belongs to philosophy. A very old question, never really resolved – see David Hume

please write more about it, im interested in philosophy. the only think i know about hume is is-ought dillema :oops:

Re: Defensive Snake Venom? A survey of pain in snakebite pat

PostPosted: Sun Nov 20, 2016 5:04 pm
by Berislav Horvatic
Michal Szkudlarek wrote:please write more about it, im interested in philosophy. the only think i know about hume is is-ought dillema :oops:

A short course in empiricist philosophy, written by a theoretical physicist, here?! No, thank you, I bear no wish to
be expelled from this forum. I was on the very brink of that peril several times. Also, I don't feel really competent.

https://en.wikipedia.org/wiki/Empiricism