An article to read

[Mark Newton]

I have put together an article discussing the relationships between morphology, general venom toxicity and predation strategies. I dont believe that scorpions with small hands and big tails are highly toxic as a result of the need to envenomate their prey and my article discusses this.

Please have a read and let me know your opinion etc....if you think it's crap, say so, I'm pretty thick skinned....

http://www.thedailylink.com/thespiralburro...ures/venom.html

cheers

 

[magikscorps]

Thanks great read.......somethings to think about, and to straighten out misconceptions...............Cheers

 

[mkieff]

Well written, and a good read. Makes you think.

 

[skinheaddave]

There is a lot of potential there, but I don't thnk it has been properly realized. I've emailed you my comments.

Cheers,
Dave

 

[~Abyss~]

This is great. A good read and vey interesting. I admit I still need to finish reading it though.
-Eddy

 

[Frédérick]

it makes sense, very nice thinking there. have you discussed the matter with professionnals?

 

[Mark Newton]

There is a lot of potential there, but I don't thnk it has been properly realized. I've emailed you my comments.

Cheers,
Dave

Thanks Dave, for making some very good points....

 

[Mark Newton]

Just to make people aware.....this article is aimed at the general public and is not in any way meant to be looked at as a scientific presentation. It is an opinion based, general article only, designed to get people thinking outside the box. It is not intended to cover all morphologies either, just the basic overall plans. I will emphasise this on the page itself, as some people have thought I was putting up a paper. I dont think it would make a very good scientific paper..LOL.

Thanks to those that have commented and given me a few ideas on making my points clearer, much appreciated.

 

[Mark Newton]

it makes sense, very nice thinking there. have you discussed the matter with professionnals?

NO...I havent discussed it with professionals, if I wished to take it farther and publish something based around it I would.

 

[phear_me]

Excellent work at the theoretical stage, but I think some of your conclusions go a little too far.

To properly conclude this you would need to first gather ample data and run a regression analysis with at least a 95% confidence interval that demonstrated a true correlation.

A note about the paragraph below:

"Why are there so few lethal scorpion species in the world?

There are in the order of 1500-2000 species of scorpion world wide, but only a very small handful would ever be considered lethal to humans or even most animals for that matter, but they all cause pain to one degree or another. Those predators that on average died after envenomation would have a lower chance of passing on genes than those smart enough to learn after experiencing the pain. Eventually, natural selection would produce predators with innate instinct to either be very careful or stay away from the scorpion, and as stated earlier, this is reflected in those creatures that mimic scorpions. It is evolutionarily advantageous to have your potential predators learn that you are dangerous. It wouldn't work if they died, learning would never take place, there would simply be a more rapid evolution of more powerful predators capable of surving the envenomation and that would mean problems for the scorpion. Just as a parasite needs to keep its host alive, so a scorpion needs to keep its predators alive."

This implies design and I believe goes too far for the mutation/selective methods of natural selection.

Also, use spell check on that article.

 

[Mark Newton]

To properly conclude this you would need to first gather ample data and run a regression analysis with at least a 95% confidence interval that demonstrated a true correlation.

A note about the paragraph below:

"Why are there so few lethal scorpion species in the world?

This implies design and I believe goes too far for the mutation/selective methods of natural selection.

Also, use spell check on that article.

Thankyou...I entirely agree, its an argument based on observation and opinion, never meant to be based on analysis of date.....just as is the popular misconception....opinion without substantive data, this is a different potential viewpoint, written to hopefully possibly expand thinking. It's up to the reader if they agree with my conclusions or not. It would need to be broken down into a number of research articles to conclude with real data.


I'm not too sure how you think it implies design, could you explain?

And yes...something I didnt do was run a spell checker....LOL.

 

[skinheaddave]

This implies design and I believe goes too far for the mutation/selective methods of natural selection.

I am also curious about this. The language may be a bit off, but is nowhere out of line with most casual discussion of evolution. The principles behind that paragraph are nowhere revolutionary -- look at the literature surrounding lepidoptera, for example, and there are plenty of examples of toxins, mimicry, adapted predators etc.

In my mind, the place where Mark makes the error of which you accuse him is in the section "What drives different body forms?" in which he suggests that the scorpions "choose" to live a certain way and that this is reflected in their morphology.

Cheers,
Dave

 

[Mark Newton]

In my mind, the place where Mark makes the error of which you accuse him is in the section "What drives different body forms?" in which he suggests that the scorpions "choose" to live a certain way and that this is reflected in their morphology.

Cheers,
Dave

Yes, 'choose' is a bad word, I'll definitely change that. Of course I meant it loosely, thinking that the reader would know what I mean. However, I stick by my logic, in that, the way in which an animal lives will be reflected in its morphology and I think this is clear in scorpions.

I'm a great believer in open discussion in science, throwing ideas and thoughts around, regardless if even they may seem a little crazy. From this comes greater thinking and thus the potential for new research to spawn.....and its fun....

 

[skinheaddave]

the way in which an animal lives will be reflected in its morphology and I think this is clear in scorpions.

Oh, most definitely. Of course this is a two way street -- since behaviour is also subject to selective pressure, a morphology can dictate a behaviour.

Cheers,
Dave

 

[Mark Newton]

Oh, most definitely. Of course this is a two way street -- since behaviour is also subject to selective pressure, a morphology can dictate a behaviour.

Cheers,
Dave

Thats right, that's why I used the example of the rock space scorpion. Due to living in tight spaces it really cant effectively used its telson while in a cramped space and so the rear end of the scorpion has gradually taken a back seat you might say. As a result of this morphology it has a very gentle behaviour as a pet for instance, one of the most harmless scorpions to handle, I cant imagine it stinging a person, that would be most odd, as a person would best be interpredated as a predator, and so the reaction is to back out rather than attack. And this is a result of its morphology, which is a result of the physical environment it occupies. This lack of use of its venom has resulted in a very weak venom pain wise, at least from the point of view as experienced by the human judge. I equate pain of the venom as a result of interaction with predators and effectivness of killing prey as a result of feeding pressures and try to indicate the relationship between the two as an obscure one, potentially unrelated.....hard to say, but I would at least assume a more painful toxin would probably have a greater effect on immobilizing prey.

 

[skinheaddave]

I equate pain of the venom as a result of interaction with predators and effectivness of killing prey as a result of feeding pressures and try to indicate the relationship between the two as an obscure one, potentially unrelated.....hard to say, but I would at least assume a more painful toxin would probably have a greater effect on immobilizing prey.

This is an area where you and I disagree. I look towards Opisthacanthus which is morphologically very similar to Liocheles etc. and also has the reduced metasoma, dorsoventral compression and extremely weak venom when it comes to defense. Yet I've seen them quickly immobilize large prey items with a sting on several occasions. Their venom is far from useless in that respect.

The theoretical avenue must also be explored. The polypeptide portion of scorpion venoms is rife with potential for taxon-specific reactions. A lot of it has to do with the tertiary structure matching well to ion channels in a lock-and-key type situation. It is far from inconceivable that different polypeptides have different effectiveness between taxons. In fact, it is so inconceivable that it has been well documented in the literature. I can't remember off-hand whether it is The Biology of Scorpions or Scorpion Biology and Research that has an interesting bit about such matters.

The serum portion of the venom also may well have different effects on different taxons. Take, for example, serotonin. This is a rather central neurotransmitter for us, but seems to have more localized effects in inverts (this being my understanding, at this point I'm treading out onto thin ice with respect to my knowledge). A lot of the pain associated with scorpion stings in us appears to come from this portion of the venom and I don't know that it would have an equivalent effect in invertebrates.

In the end, however, I don't know the answer here. I know that there are separate venom components that are more useful as defense or as prey immobilization. I don't know, however, how these relate to shared components and how legitimate your assumptions truly are. A good thorough literature search may get you closer to that answer. The important point, however, is that if the connection should be proven false, it would call into question some of your conclusions. I know you have repeatedly said that your paper is not a scientific one and is basically just your own ramblings ... but I see no reason why you shouldn't attempt to give it some legitimacy.

Cheers,
Dave

 

[Mark Newton]

Thanks Dave

This is an area where you and I disagree. I look towards Opisthacanthus which is morphologically very similar to Liocheles etc. and also has the reduced metasoma, dorsoventral compression and extremely weak venom when it comes to defense. Yet I've seen them quickly immobilize large prey items with a sting on several occasions. Their venom is far from useless in that respect.

I dont think we disagree at all, in fact we seem to be on exactly the same page. One of the reasons I said the relationship between a venoms pain and killing efficacy is an obscure one. I also said there 'might' be a relationship between the two and maybe in some cases there is, others not, its very hard to know and I'm sure it would vary as venoms as protein complexes are highly variable.
I'd say that Liocheles venom is far from useless to, it seems to work very well in the instances I've seen it used, even though the scorpions as adults often dont use it.

The theoretical avenue must also be explored. The polypeptide portion of scorpion venoms is rife with potential for taxon-specific reactions. A lot of it has to do with the tertiary structure matching well to ion channels in a lock-and-key type situation. It is far from inconceivable that different polypeptides have different effectiveness between taxons. In fact, it is so inconceivable that it has been well documented in the literature. I can't remember off-hand whether it is The Biology of Scorpions or Scorpion Biology and Research that has an interesting bit about such matters.

Absolutely. Look at Ichneumonid wasps for instance, they all pack a powerful sting and yet have species specific venom that immobilises the immune systems of their particular prey species.

The serum portion of the venom also may well have different effects on different taxons. Take, for example, serotonin. This is a rather central neurotransmitter for us, but seems to have more localized effects in inverts (this being my understanding, at this point I'm treading out onto thin ice with respect to my knowledge). A lot of the pain associated with scorpion stings in us appears to come from this portion of the venom and I don't know that it would have an equivalent effect in invertebrates.

Yes, absolutely, couldnt agree more.

In the end, however, I don't know the answer here. I know that there are separate venom components that are more useful as defense or as prey immobilization. I don't know, however, how these relate to shared components and how legitimate your assumptions truly are. A good thorough literature search may get you closer to that answer. The important point, however, is that if the connection should be proven false, it would call into question some of your conclusions. I know you have repeatedly said that your paper is not a scientific one and is basically just your own ramblings ... but I see no reason why you shouldn't attempt to give it some legitimacy.

I dont know either, just throwing some ideas around to generate some thinking, and maybe its working, quite a few people have written to me saying its making them think outside the box.

Which conclusion/s are you actually referring to? I guess the first one. Maybe I should rephrase it. I am referring to the venom action against predators, as clearly, its the predator/prey interaction that is creating selection pressure on the venom predator component, I stated somewhere that prey action and predator action of the venom is likely independent.....and that the relationship is an obscure one.

In conclusion:
• Predator – Prey interaction has resulted in opportunistic scorpions developing relatively powerful toxins.