This reminds me of Alexander Shulgin, who died a few days ago (there was an article here on HN [0]). Sometimes the most interesting and useful science is self-experimentation!
> most cases require intravenous opioid analgesia ...
and
> One unusual symptom associated with the syndrome is a feeling of "impending doom".[13] Patients have been reported as being so certain they are going to die, they beg their doctors to kill them to get it over with.
> On the television program Super Animal, a woman compared her pain from childbirth to her experience with Irukandji syndrome: "It's like when you're in labor, having a baby, and you've reached the peak of a contraction—that absolute peak—and you feel like you just can't do it anymore. That's the minimum that [Irukandji] pain is at, and it just builds from there."
(from the comments which have no shortage of bug bite stories...)
"The guy should have let one bug sting him on the back of each hand, then see which hand grabbed the other in pain. That way he could compare them semi-directly, sort of like the rock hardness scratch tests. That’d involve a lot of extra stings, but it’s for a good cause..."
The symptoms as described in Wikipedia seem far less severe. He may have had either an abnormal sensitivity or received an unusually large dose of the venom.
Thankfully the Black Widow is one of the dumbest spiders I've every encountered. Amazingly easy to kill if you can be calm about it. (I feel like I should be knocking on wood now.) I don't know how many varieties there are though, so YMMV.
The only time I've definitively seen one was in my kitchen. I put it in a Tupperware and let it loose in the yard. It was so slow moving that I was never particularly concerned about being bit.
I had no idea the bite was that bad or I would have just finished it off instead.
Yeah these are one of the few spiders I kill on sight instead of gently moving to the yard.
Pretty much as soon as I find one I immediately drop whatever I'm doing to make sure it's out of my living space as quickly as possible before I lose track of it.
I lived for a few years in a particularly widow-prone area and had many black widows in the house and garage. I eventually realized that the daddy-long-legs variant in my house seemed to compete handily with them. So I stopped cleaning webs and found I had far fewer black widows. My house appeared rather shabby though. Tradeoffs.
For some reason, your comment made me imagine a hacker forum filled with black widow spiders talking about stuff, and one of them posts, "Thankfully the human is one of the dumbest animals I've ever encountered. Amazingly easy to kill if you can be calm about it."
I think the modern definition of "cakewalk" was intended here that does not have the racial connotations [1]:
an easy contest to win
an easy task
While the background on the word is interesting (I'll admit that I was unaware of it), the word does not have those racial connotations in conversation today.
At nearly 50 years of age, I have never before been aware of any defintion for "cakewalk" other than "easy task" and have never heard the word used in any context for which that definition didn't make sense.
I don't see any value in trying to infer racial slurs where clearly none was intended. Focus on the real ones.
This entire conversation is bizarre. Just because something was done by black people doesn't give it 'racial connotations.' It's not a racial slur, or some cliche based on qualities ascribed to black people by white ones. It's something black people did, which rose to popularity (in exaggerated form) for a period of time amongst whites.
I understand sometimes how navigating discussion about race feels like walking through a minefield to white people.
That is interesting! I have recollections as a kid growing up in Kentucky in the early 70's of our elementary school holding cake walks as fund raisers. I was not aware of any racial overtones then, but it was Kentucky and I was young and staggeringly clueless.
If you read your own link, you would realize that, insofar as "cakewalk" has "racial connotations" (that's quite disputable -- it certainly has a history linked to racial issues, but "history" and "connotations" aren't the same thing), "piece of cake" (which you suggest as a preferred alterantive) is equally tainted as it directly derives from the use of "cakewalk" that you find troubling, as well has having the same meaning with regard to something easy.
> If you read your own link, you would realize that, insofar as "cakewalk" has "racial connotations" (that's quite disputable -- it certainly has a history linked to racial issues, but "history" and "connotations" aren't the same thing),
There's no need to be snarky. In the same link I cited, it notes that this etymology of "piece of cake" is hypothesized but uncertain (which easily verified elsewhere)[0][1].
I agree that connotations and history aren't the same, and in fact, if we accept as fact the premise that the etymology for both phrases is the same, this example only underscores that fact even further.
Even if we assume the etymology is the same, I posit that "piece of cake" has been appropriated and sanitized far more than "cakewalk" has. This is an example of where etymological history and connotations diverge[2].
[2] An example of the same phenomenon working in reverse would be the word "niggardly", which has a completely non-racist etymology[3], but nevertheless may carry racial connotations in use[4]. The fact that the word is of Norse origin doesn't change the connotation it carries when used, even if undeservedly.
A friend of mine got bit by one once. She showed up in the hospital and calmly explained that she got bit by a black widow and asked for the anti venin. They looked at her skeptically until she pulled out a baggie with the dead widow in it. Then they treated her right away.
If you find yourself bit, kill the spider and take it with you. You'll forestall any complaints and questions about whether you're sure it was a black widow and shorten the time to diagnose and begin treatment. (I.E. You'll experience far fewer of the symptoms the sooner you get treated.)
(Unfortunately as of a few days ago, there is still a storage of supplies for the antivenin: http://www.ashp.org/menu/DrugShortages/CurrentShortages/bull... So some hospitals may not have it in stock if they normally would. But apparently emergency supplies remain.)
I've just been bitten by a spider, and I'm supposed to calmly and quickly corner it, kill it, and scrape it into a baggie to show to the doctor? I'm supposed to do this after reading this article, knowing what's ahead of me?
Some people are more useful in emergencies than others. You're right that some will fall to pieces, but I'm the type with presence of mind and I would be doing that as quickly as I could rather than waiting until I caved in to the pain.
Per the description, it's not that bad until the reaction spreads, so you want to take care of something like this before your feel like you're about to die.
They'll eventually diagnose you and get around to tracking down some antivenin without it.
If you lose track of it, it's probably more important to get to the hospital faster than trying to track it down. But if you can nab it, it'll save you time and you won't have to wonder where the spider went off to later, since many people encounter these things inside their homes.
They do milk spiders, but antivenom is generally created by injecting small amounts into animals like horses until they build up antibodies that are used to create antivenom.
Similarly one of my cats let out an almighty howl last week, and when I went to investigate I saw a spider sitting next to his paw -- my conclusion he had been bitten by the spider.
By capturing it I was able to look up the species to tell if I needed to rush him to the vet.
Tried the link. Black Widows are all over the place in California but they don't show up under that filter. Perhaps the authors of the "numerous scientific publications" they cite need to come visit my garage.
Bonus to the kill-and-bring-to-the-hospital method of spider bites: over millions of years genetic pressure will teach spiders their lesson and they'll stop biting humans.
I was bitten by a brown recluse as a kid; I had a scar the size of a quarter on my leg from the skin necrosis. The only lasting effect was an acute arachnophobia.
I was bitten by a brown house spider (Steatoda grossa) years ago and found the dead spider in my bed sheet.
It left me feeling sick, unable to eat and struggling to drink for days due to the pain from my throat right through to my abdomen. Apparently the redback anti-venom works for it.
Kill them on sight now along with the very rare redback or white-tail and lots of huntsman. We also get a few black house spiders which I generally leave unless they are moving about.
As mentioned in another comment nothing beats an irukandji for pain. It also has an interesting story of self-experimentation to pin down the jellyfish as the cause of Irukandji Syndrome:
I was bit by a brown recluse as a kid. The symptoms were nothing like this but it did create a large nasty looking hole in my calf that seemed to grow for a couple of weeks rotting the flesh. It was unpleasant but not all that painful considering.
In addition to the recluse bite, I have been stung by bees, wasps, jellyfish and a scorpion but the worst was from nothing less than a caterpillar. It happened twice... two different kinds of caterpillars (the first one I put my hand on climbing a tree, the second I actually picked up). It was not to the level described in the article, but some of the same type symptoms appeared. My arm ached with horrible muscle pains, I felt symptoms throughout my body and I felt extremely ill for a day or so.
I was around 10 or 12 at the time, we had just moved to Florida and I was quite surprised to learn that some caterpillars stung. I don't live there anymore but am still extremely wary of caterpillars that have any fuzz or hair.
So, because the old African-American entertainment of a cakewalk never gained the same eminence earned (deservedly) by jazz or tap, then it is to be considered racist and on par with a slur? The discussion over this matter seems itself to be an entertainment and a craven one.
Disclaimer: My piece had nothing to do with race nor cakewalks, I have no idea what they have to do with anything, and you are replying to a deleted comment below....
In grade school, there was a tree we used to play near after school, and a fellow student cautioned several times about "asps" [asp caterpillars] around that tree. I never actually saw one, but he must have known about the things from somewhere else and had seen one in the vicinity.
These things are serious, at least they were for me. Worst animal trauma ever. I don't know if anyone has ever died from one but I think they should be more publicized.
If anyone has access to the 1934 paper Blair wrote about this, I'd love to read it. My address is in my HN profile.
SPIDER POISONING: EXPERIMENTAL STUDY OF THE EFFECTS OF THE
BITE OF THE FEMALE LATRODECTUS MACTANS IN MAN
A. W. BLAIR, M.D.
Arch Intern Med (Chic). 1934;54(6):831-843.
doi:10.1001/archinte.1934.00160180003001.
What amazes me is the question: what kind of evolutionary pressure would drive creatures to develop stings and venom this viscious. I would have thought nature would stop optimizing once a sting is a good enough deterrent. It is as if someone said, no, I would optimize the crap out of this chemical weapon.
I have always been intrigued by how much does the effect generalize across the victim species. Consider tarantula wasps, their sting take pain and suffering to new heights (for humans). But really what the wasps use it for, primarily, is to temporarily immobilize a tarantula so that it can lay eggs on it. The hatchlings end up eating the tarantula. If temporary immobilization is the main use case (surely not the only use case), must it be this painful. Is the tarantula in as much pain and if so what purpose is that serving ? It seems something that gives them a pleasure trip makes more sense.
* A more powerful venom will work faster and more reliably.
* This is not only a very powerful, but also a very efficient venom. More efficient venom reduces manufacturing costs (as only a few molecules are needed).
* Chance probably have played a role here. Black widows hardly had any pressure to evolve a specific venom against humans.
As our nerve system is based on the same basic molecules as every other land creature, but not the same structure, a venom that is good enough to kill a mouse may have a devastating (albeit non-fatal) effect on us.
I'm already speculating, so I may be cruel: maybe the spider wants to paralyze the mouse, but keep him alive for a few days so the flesh stays fresh as they eat it.
"I'm already speculating, so I may be cruel: maybe the spider wants to paralyze the mouse, but keep him alive for a few days so the flesh stays fresh as they eat it."
Another layman here, but I believe spider venom is designed to pre-digest food to some extent, rather than to keep it fresh.
Snake venom of the rattlesnake variety certainly is; the fangs are the first line of the digestive system. Black mamba venom is a neurotoxin. It's remarkable how diverse venom is.
I imagine that while it doesn't need to be this vicious for humans, they have evolved this to deal with other large animals. Humans tend to avoid getting bitten so we haven't evolved the defences other animals have. We are pretty weak creatures all things considered.
Have you seen that youtube clip of a honey badger attacking a poisonous snake? He is bitten repeatedly. He falls unconscious, and later wakes up and continues eating the snake. That's the kind of predator poison gets stronger and stronger for.
- Spiders have huge litters.
- It may be that the evolutionary path is more driven by the enzyme chemistry than the efficacy of the venom. Mighta come up with a nasty version and then change more or less stopped, purely by accident. Evoluton arrives at solutions, not optima.
- Given the general proximity these spiders tend to have with humans, their prevalence could be completely accidental. See also grackles, other creatures that are symbiotes to us.
Now I wonder what the metabolic load from producing venom in venomous creatures works out to.
I wonder if the devastating effect on us may be a sort of coincidence. It's chemical code running on a different (but similar) biological chip-set than evolved for, and just happens to unleash hell on our human hardware.
Naturally selection is a process of random mutations. The ancient ancestor of the first black widow might not have been some peculiar middle ground between benign and lethal, yet the random mutation of offspring which proliferated merely happened to be highly deadly.
Along that vein, I wonder if there have been random black window mutations since which have been even more lethal, but since this did not present a significant survival advantage, they did not live long enough to become a distinct species.
There's a paper on latrotoxins available, "Molecular Evolution of α-Latrotoxin, the Exceptionally Potent Vertebrate Neurotoxin in Black Widow Spider Venom":
Exactly. A stronger venom doesn't only mean that the spider can kill prey more efficiently. It also means that those individuals with the stronger venom mutation have higher chances of breeding. They can kill more efficiently and faster and thus have higher chances to survive long enough to reproduce.
In evolution the mutation that leads in the long term to higher chances of reproduction usually wins.
> The ancient ancestor of the first black widow might not have been some peculiar middle ground between benign and lethal, yet the random mutation of offspring which proliferated merely happened to be highly deadly.
This is possible but not very likely in reality.
We expect evolution to be incremental, for the following reasons:
First of all, it's very unlikely that any mutation would get to "Surprise! Lethal!" venom unless the species is already geared up to produce something venom-like, and also to store venom and to protect itself from its own venom. There's a whole bunch of new functions that are needed to be venomous, and it's vanishingly unlikely that they will all suddenly appear at the same time, even at evolutionary scale.
IMO mutations normally have small positive effects and large negative effects: they are more likely to delete or - if you're lucky - alter some existing function and very unlikely to build a whole new function (compare: a small random change to your computer code).
Even if super-lethal venom was to somehow appear overnight, then in order to reach 100% prevalence it must provide such an immediate advantage that the non-lethal spiders die out and only super-lethal spiders proliferate.
But the non-lethal spiders were surviving pretty well in order to reach that point. So, there's no reason to believe the non-lethal spiders were in particular danger or that lethal venom was needed - normally, the "Surprise! Lethal!" variant line would just quietly die out (as almost all variants do) leaving the wild non-lethal type.
As I say, the random mutation explanation is possible but not really practical.
A far more plausible scenario is an "arms race" - where venomous functions develop over time, while predators and prey develop immunity over time - as the predators (honey badger) start evolving coping mechanisms, stronger venom is needed.
Purely speculation, but perhaps the target species evolved defenses. So it evolved a more potent venom. Another evolutionary arms race that results in highly optimized weapons. It just happens we have similar biology to the target species and none of the defenses.
> I would have thought nature would stop optimizing once a sting is a good enough deterrent.
I believe you are probably right about this: but the spider venom was probably developed in an arms race with some {predator/prey} species. In your 'tarantula hawk' example, the venom must work on the tarantula, and the tarantula must do its evolutionary best to protect itself from the venom. This combination allows the venom to become extremely effective.
Or, given that it's the black "widow", maybe the venom is a result of sexual selection[0], which tends to have crazily extreme results. A spider fetish, if you like.
But, the sting/venom is not designed for humans (it just happens to work on them), and humans as a species have no reason to develop better protection. Humans typically aren't a target of the bites and almost always recover with no long-term effect. It isn't really designed to work on humans. But, it still hurts (and maybe that's a nice side benefit for a reclusive spider).
I often wonder this when thinking about the local fauna here in Australia. So much of it can kill a mammal of human size ridiculously quickly, but there really isn't anything in the fossil record to warrant such destructive power.
It's like the insects and snakes (and lots of other animals) of Australia got caught up in the equivalent of a cold war that has led to mutually assured destruction on both sides.
In the case of the Sydney funnelweb, it's pure coincidence.
The spider is much more toxic to primates than any other type of animal, but evolved in Australia, with no primates.
The "selection" that's going on here is in our attention: our gaze fixates on the species that have poison or venom that's particularly potent against us, out of the thousands of species that have poison or venom of some sort.
My 6 yr-old daughter asked me to get rid of a spider from her room. In I went with a "ho ho ho, of course dear" fatherly attitude to find a mature female Black Widow sat on the rocker switch of her bedside lamp. I calmly asked my little girl to go fetch her mother.
I know the feeling. Once last year my four year old refused to go to sleep, yelling about monsters in his room. Somewhat exasperated, I went into his room and turned on the light to find the biggest scorpion I'd ever seen crawling up his wall. I had a hell of a time arguing with him when he got convinced about monsters lurking for six months afterwards.
Big scorpions are not dangerous. The most dangerous scorpions tend to be smaller ones. This I leaned from Sahara desert natives. I found a small one under a rock and played with it. Those people got crazy at me.
" A dose of the venom contains only a few molecules of the neurotoxin, which has a high molecular weight--in fact, the molecules are large enough to be seen under an ordinary microscope."
Does anyone have another source for this, maybe a photo? I spent some time looking around but I can't find anything relevant and it seems a little hard to believe.
Unless the molecular weight is about 10 pentillion (?) you ain't gonna see diddly! Avogadro's number is a big thing. (6 x 10^23). Now agreed that you don't need a mole of something (especially w/ a high molecular weight) to be able to see it in a microscope. But it's probably at least w/in 4 to 5 orders of magnitude of the right number.
It's wrong, the molecules are many orders of magnitude smaller than is possible to see.
The main black widow venom is alpha-Latrotoxin (http://en.wikipedia.org/wiki/Latrotoxin), which is a 130 kDa protein according to wikipedia. That's large for a protein but there are bigger. Eukaryotic ribosomes are around 2500 kDa, but even they are completely invisible at 20 nm wide, and there are a thousands-millions of them per cell.
I had a great aunt die from a bite by a Brown Recluse. All this did was solidify my fear of spiders in general. What I remember of it (I was young when this happened) was that the bite was misdiagnosed initially as nothing serious and she was sent home with a topical ointment.
Things went downhill fast. I know that the limb that was bitten was amputated, and that by the time they figured out the cause her fate was sealed. I know they're supposed to be beneficial insects but I kill just about every one I encounter to this day.
At least the Black Widow is distinctive. It's unmistakable if you see one.
More generally, they like dark, cool places where they aren't likely to be disturbed. For a few years in my childhood, my mother and I shared a small house with a widow who'd set up housekeeping between the toilet tank and the wall; we got along fine, no doubt as much due to her ability to keep well fed in an old and not well constructed rural home, as to the respect we were careful to maintain in our dealings with her.
I've been bitten by a Redback Spider (related to the Black Widow, I believe), twice! As a kid I was fascinated by insects and spiders, and used to love watching them for hours. As it turns out, Redbacks hurt a lot, its one of the worst bites I've experienced. A sharp sensation, followed by a burning and prickliness. Horrible. Parents took me to the hospital straight away, as it made me feel really sick (I was 10 years old the first time, and 11 the second). After the second time I sort of learned my lesson...
This thread, more than any other, illustrates why the majority of posters should be ignored.
Approximately 50% of the posts are preceded with a variation of -
"I am just speculating but..."
Why on earth would 99.9% of the people on this thread think they have the expertise to offer an opinion of the evolution of arachnid venom is beyond me.
Fascinating article, even more fascinating watching humans debate like blind people in the dark.
Brown Recluse spiders are very common where I live and I've known countless people who have been bitten by them and ended up with a necrosis wound.
Unfortunately the Brown Recluse spider looks very similar to many harmless spiders, so if there is a brown spider I usually don't take any chances unless I can positively identify it.
Supposedly Black Widows are in my area also, but I've never seen one.
I'm not sure how I feel about this though: http://www.spiders.us/files/pholcus-phalangioides-5.jpg Spiders don't creep me out at all, but a large group of spiders would, even though I've heard that their fangs cannot pierce human skin.
BTW, changing the original articles main layout table (15 year old site I'm guessing) to 1800px makes the article much more readable. I found it hard to read the 270px wide article with 1 foot of white space on each side.
91 comments
[ 4.9 ms ] story [ 152 ms ] thread[0] https://news.ycombinator.com/item?id=7839226
Yikes!
http://en.wikipedia.org/wiki/Irukandji_syndrome
Choice quotes:
> most cases require intravenous opioid analgesia ...
and
> One unusual symptom associated with the syndrome is a feeling of "impending doom".[13] Patients have been reported as being so certain they are going to die, they beg their doctors to kill them to get it over with.
> On the television program Super Animal, a woman compared her pain from childbirth to her experience with Irukandji syndrome: "It's like when you're in labor, having a baby, and you've reached the peak of a contraction—that absolute peak—and you feel like you just can't do it anymore. That's the minimum that [Irukandji] pain is at, and it just builds from there."
1.8 Bullhorn acacia ant: A rare, piercing, elevated sort of pain. Someone has fired a staple into your cheek.
[1] http://scienceblogs.com/retrospectacle/2007/05/16/schmidt-pa...
(from the comments which have no shortage of bug bite stories...) "The guy should have let one bug sting him on the back of each hand, then see which hand grabbed the other in pain. That way he could compare them semi-directly, sort of like the rock hardness scratch tests. That’d involve a lot of extra stings, but it’s for a good cause..."
https://en.wikipedia.org/wiki/Latrodectism
I don't think people usually do that
I had no idea the bite was that bad or I would have just finished it off instead.
Pretty much as soon as I find one I immediately drop whatever I'm doing to make sure it's out of my living space as quickly as possible before I lose track of it.
[1]http://www.merriam-webster.com/dictionary/cakewalk
I don't see any value in trying to infer racial slurs where clearly none was intended. Focus on the real ones.
I understand sometimes how navigating discussion about race feels like walking through a minefield to white people.
There's no need to be snarky. In the same link I cited, it notes that this etymology of "piece of cake" is hypothesized but uncertain (which easily verified elsewhere)[0][1].
I agree that connotations and history aren't the same, and in fact, if we accept as fact the premise that the etymology for both phrases is the same, this example only underscores that fact even further.
Even if we assume the etymology is the same, I posit that "piece of cake" has been appropriated and sanitized far more than "cakewalk" has. This is an example of where etymological history and connotations diverge[2].
[0] https://en.wikipedia.org/wiki/Cakewalk#Modern_times
[1] http://www.etymonline.com/index.php?term=cakewalk
[2] An example of the same phenomenon working in reverse would be the word "niggardly", which has a completely non-racist etymology[3], but nevertheless may carry racial connotations in use[4]. The fact that the word is of Norse origin doesn't change the connotation it carries when used, even if undeservedly.
[3] https://en.wikipedia.org/wiki/Niggardly#Word_origins
[4] https://en.wikipedia.org/wiki/Niggardly#David_Howard_inciden...
If you find yourself bit, kill the spider and take it with you. You'll forestall any complaints and questions about whether you're sure it was a black widow and shorten the time to diagnose and begin treatment. (I.E. You'll experience far fewer of the symptoms the sooner you get treated.)
(Unfortunately as of a few days ago, there is still a storage of supplies for the antivenin: http://www.ashp.org/menu/DrugShortages/CurrentShortages/bull... So some hospitals may not have it in stock if they normally would. But apparently emergency supplies remain.)
Per the description, it's not that bad until the reaction spreads, so you want to take care of something like this before your feel like you're about to die.
They'll eventually diagnose you and get around to tracking down some antivenin without it.
If you lose track of it, it's probably more important to get to the hospital faster than trying to track it down. But if you can nab it, it'll save you time and you won't have to wonder where the spider went off to later, since many people encounter these things inside their homes.
https://www.youtube.com/watch?v=8svYyihCqsg
By capturing it I was able to look up the species to tell if I needed to rush him to the vet.
See: http://www.spiders.us/species/filter/california/ (also useful for human bites, I'm sure) Obviously change the state for yours.
Turned out spider was harmless, cat was fine!
http://www.spiders.us/species/filter/california/?PageSpeed=n...
It left me feeling sick, unable to eat and struggling to drink for days due to the pain from my throat right through to my abdomen. Apparently the redback anti-venom works for it.
Kill them on sight now along with the very rare redback or white-tail and lots of huntsman. We also get a few black house spiders which I generally leave unless they are moving about.
As mentioned in another comment nothing beats an irukandji for pain. It also has an interesting story of self-experimentation to pin down the jellyfish as the cause of Irukandji Syndrome:
http://lifeinthefastlane.com/jack-barnes-and-the-irukandji-e...
You can do certain things to minimise your risk of getting bitten, or not.
https://www.youtube.com/watch?v=Wynx1ukwdVA&feature=kp
I was bit by a brown recluse as a kid. The symptoms were nothing like this but it did create a large nasty looking hole in my calf that seemed to grow for a couple of weeks rotting the flesh. It was unpleasant but not all that painful considering.
In addition to the recluse bite, I have been stung by bees, wasps, jellyfish and a scorpion but the worst was from nothing less than a caterpillar. It happened twice... two different kinds of caterpillars (the first one I put my hand on climbing a tree, the second I actually picked up). It was not to the level described in the article, but some of the same type symptoms appeared. My arm ached with horrible muscle pains, I felt symptoms throughout my body and I felt extremely ill for a day or so. I was around 10 or 12 at the time, we had just moved to Florida and I was quite surprised to learn that some caterpillars stung. I don't live there anymore but am still extremely wary of caterpillars that have any fuzz or hair.
http://en.wikipedia.org/wiki/Megalopyge_opercularis
From the description, I think of it like a venomous version of those fine-spined cacti often seen in miniature cactus arrangements.
The other was something like this http://www.missouribotanicalgarden.org/Portals/0/Gardening/G...
(you can see why I picked him up).
These things are serious, at least they were for me. Worst animal trauma ever. I don't know if anyone has ever died from one but I think they should be more publicized.
http://kimberlymoynahan.com/2012/10/of-mites-and-men/
I have always been intrigued by how much does the effect generalize across the victim species. Consider tarantula wasps, their sting take pain and suffering to new heights (for humans). But really what the wasps use it for, primarily, is to temporarily immobilize a tarantula so that it can lay eggs on it. The hatchlings end up eating the tarantula. If temporary immobilization is the main use case (surely not the only use case), must it be this painful. Is the tarantula in as much pain and if so what purpose is that serving ? It seems something that gives them a pleasure trip makes more sense.
* A more powerful venom will work faster and more reliably.
* This is not only a very powerful, but also a very efficient venom. More efficient venom reduces manufacturing costs (as only a few molecules are needed).
* Chance probably have played a role here. Black widows hardly had any pressure to evolve a specific venom against humans.
As our nerve system is based on the same basic molecules as every other land creature, but not the same structure, a venom that is good enough to kill a mouse may have a devastating (albeit non-fatal) effect on us.
I'm already speculating, so I may be cruel: maybe the spider wants to paralyze the mouse, but keep him alive for a few days so the flesh stays fresh as they eat it.
Another layman here, but I believe spider venom is designed to pre-digest food to some extent, rather than to keep it fresh.
Have you seen that youtube clip of a honey badger attacking a poisonous snake? He is bitten repeatedly. He falls unconscious, and later wakes up and continues eating the snake. That's the kind of predator poison gets stronger and stronger for.
- Spiders have huge litters. - It may be that the evolutionary path is more driven by the enzyme chemistry than the efficacy of the venom. Mighta come up with a nasty version and then change more or less stopped, purely by accident. Evoluton arrives at solutions, not optima. - Given the general proximity these spiders tend to have with humans, their prevalence could be completely accidental. See also grackles, other creatures that are symbiotes to us.
Now I wonder what the metabolic load from producing venom in venomous creatures works out to.
Naturally selection is a process of random mutations. The ancient ancestor of the first black widow might not have been some peculiar middle ground between benign and lethal, yet the random mutation of offspring which proliferated merely happened to be highly deadly.
Along that vein, I wonder if there have been random black window mutations since which have been even more lethal, but since this did not present a significant survival advantage, they did not live long enough to become a distinct species.
http://mbe.oxfordjournals.org/content/30/5/999.full
It's way over my head though and I actually have no idea if it's backing up or refuting your claim.
Exactly. A stronger venom doesn't only mean that the spider can kill prey more efficiently. It also means that those individuals with the stronger venom mutation have higher chances of breeding. They can kill more efficiently and faster and thus have higher chances to survive long enough to reproduce.
In evolution the mutation that leads in the long term to higher chances of reproduction usually wins.
This is possible but not very likely in reality.
We expect evolution to be incremental, for the following reasons:
First of all, it's very unlikely that any mutation would get to "Surprise! Lethal!" venom unless the species is already geared up to produce something venom-like, and also to store venom and to protect itself from its own venom. There's a whole bunch of new functions that are needed to be venomous, and it's vanishingly unlikely that they will all suddenly appear at the same time, even at evolutionary scale.
IMO mutations normally have small positive effects and large negative effects: they are more likely to delete or - if you're lucky - alter some existing function and very unlikely to build a whole new function (compare: a small random change to your computer code).
Even if super-lethal venom was to somehow appear overnight, then in order to reach 100% prevalence it must provide such an immediate advantage that the non-lethal spiders die out and only super-lethal spiders proliferate.
But the non-lethal spiders were surviving pretty well in order to reach that point. So, there's no reason to believe the non-lethal spiders were in particular danger or that lethal venom was needed - normally, the "Surprise! Lethal!" variant line would just quietly die out (as almost all variants do) leaving the wild non-lethal type.
As I say, the random mutation explanation is possible but not really practical.
A far more plausible scenario is an "arms race" - where venomous functions develop over time, while predators and prey develop immunity over time - as the predators (honey badger) start evolving coping mechanisms, stronger venom is needed.
I believe you are probably right about this: but the spider venom was probably developed in an arms race with some {predator/prey} species. In your 'tarantula hawk' example, the venom must work on the tarantula, and the tarantula must do its evolutionary best to protect itself from the venom. This combination allows the venom to become extremely effective.
Or, given that it's the black "widow", maybe the venom is a result of sexual selection[0], which tends to have crazily extreme results. A spider fetish, if you like.
But, the sting/venom is not designed for humans (it just happens to work on them), and humans as a species have no reason to develop better protection. Humans typically aren't a target of the bites and almost always recover with no long-term effect. It isn't really designed to work on humans. But, it still hurts (and maybe that's a nice side benefit for a reclusive spider).
[0] https://en.wikipedia.org/wiki/Sexual_selection
It's like the insects and snakes (and lots of other animals) of Australia got caught up in the equivalent of a cold war that has led to mutually assured destruction on both sides.
The spider is much more toxic to primates than any other type of animal, but evolved in Australia, with no primates.
The "selection" that's going on here is in our attention: our gaze fixates on the species that have poison or venom that's particularly potent against us, out of the thousands of species that have poison or venom of some sort.
(Source: Somewhere in this otherwise sort of stupid video: https://www.youtube.com/watch?v=myh94hpFmJY )
Wasn't sad to move out of that apartment.
Does anyone have another source for this, maybe a photo? I spent some time looking around but I can't find anything relevant and it seems a little hard to believe.
The main black widow venom is alpha-Latrotoxin (http://en.wikipedia.org/wiki/Latrotoxin), which is a 130 kDa protein according to wikipedia. That's large for a protein but there are bigger. Eukaryotic ribosomes are around 2500 kDa, but even they are completely invisible at 20 nm wide, and there are a thousands-millions of them per cell.
Things went downhill fast. I know that the limb that was bitten was amputated, and that by the time they figured out the cause her fate was sealed. I know they're supposed to be beneficial insects but I kill just about every one I encounter to this day.
At least the Black Widow is distinctive. It's unmistakable if you see one.
- They like to hang out in wood piles or corners of the garage.
- Their webs look "messy". Also the webs are pretty tough and don't tear easily. You can pluck them like guitar strings.
Anyone have a clearer explanation for the psychopharmacology at work here?
Approximately 50% of the posts are preceded with a variation of -
"I am just speculating but..."
Why on earth would 99.9% of the people on this thread think they have the expertise to offer an opinion of the evolution of arachnid venom is beyond me.
Fascinating article, even more fascinating watching humans debate like blind people in the dark.
Unfortunately the Brown Recluse spider looks very similar to many harmless spiders, so if there is a brown spider I usually don't take any chances unless I can positively identify it.
Supposedly Black Widows are in my area also, but I've never seen one.
I do let these guys stay in my house most of the time: http://www.spiders.us/species/pholcus-phalangioides/
I'm not sure how I feel about this though: http://www.spiders.us/files/pholcus-phalangioides-5.jpg Spiders don't creep me out at all, but a large group of spiders would, even though I've heard that their fangs cannot pierce human skin.
BTW, changing the original articles main layout table (15 year old site I'm guessing) to 1800px makes the article much more readable. I found it hard to read the 270px wide article with 1 foot of white space on each side.