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In an episode of Peppa Pig, one of the characters says that spiders are very very small, and that they can’t hurt you.

Broadcasters in Australia have avoided broadcasting the episode involved, because they’re worried that viewers will regard the claim as factually true.

Are spiders unable to hurt people? Also, does size have anything to do with whether they can harm you?

I’m primarily interested in whether spiders are harmful to humans, not whether they can affect pigs, and I’m interested in whether it’s true in all countries, though if it’s untrue worldwide, I’d like to know if it is at least true in the country Peppa Pig was created in (the UK), as opposed to the deathworld which is Australia.

Oddthinking
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Andrew Grimm
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  • Comments are not for extended discussion; this conversation has been [moved to chat](https://chat.stackexchange.com/rooms/92354/discussion-on-question-by-andrew-grimm-are-spiders-unable-to-hurt-humans-especi). – Sklivvz Apr 12 '19 at 09:03

4 Answers4

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The answer is that spiders definitely can hurt you. While you may not be likely to be killed, spiders can absolutely hurt you, whether from a large one's bite (whether venomous or not) or from any venomous spider.

Australia is probably the best case here, and while they have only had one death from spider bite in 40 years (from a redback bite) this is considered to be mostly because:

an effective antivenom for redback spiders was developed in 1956, and one for funnel-web spiders in 1980.

from australianmuseum.net.au

Also on that page:

...on current evidence the most dangerous spiders in the world are funnel-web spiders (Atrax and Hadronyche species), Redback Spiders and their relations (Latrodectus species), Banana Spiders (Phoneutria species) and Recluse Spiders (Loxosceles species). In Australia, only male Sydney Funnel Web Spiders and Redback Spiders have caused human deaths, but none have occurred since antivenoms were made available in 1981.

In the UK (from sciencefocus.com):

three common spiders that are capable of biting you: the cellar spider, the woodlouse spider and the false widow spider. Their bites are painful and have been known to cause swelling for a few hours. In 2014 a 60-year-old woman died after being bitten by a false widow spider.

The false widow, cellar, woodlouse and redback spiders are all pretty small, at around 1cm. A funnel-web can be up to about 5cm, so that probably doesn't count as small

Anecdotally, my son was bitten by a false widow in the summer of 2018 in Scotland, and after falling very ill and having his entire forearm swell up, with the central bite area becoming necrotic, he required emergency treatment, was in hospital for surgery, and a few days stay in the plastic surgery ward at St. Johns Hospital in Livingston. He still has a rather nasty scar on his arm, but thus far has not developed any strange powers...although he certainly sees a lot more spiders now, so maybe that's heightened alertness, maybe he attracts them...

Rory Alsop
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    Just to be clear, the last paragraph is an anecdote, and hence not strong evidence that spider bites can't give people strange superpowers. – Oddthinking Apr 11 '19 at 01:34
  • Comments are not for extended discussion; this conversation has been [moved to chat](https://chat.stackexchange.com/rooms/92355/discussion-on-answer-by-rory-alsop-are-spiders-unable-to-hurt-humans-especially). – Sklivvz Apr 12 '19 at 09:05
  • It feels weird that you start with a positive answer (that they can hurt you) and proceed to only give stories about few-and-far-between deaths. I feel like it'd be more relevant to give news or research on "harmful" effects, instead of just that no-one in Australia has died from it in almost 40 years (though some unknown number harmed) – Delioth Apr 12 '19 at 18:53
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    There is apparently no scientific evidence that cellar spiders are venomous for people (https://spiders.ucr.edu/daddylonglegs.html) and anecdotal evidence from a mythbusters episode that they can bite but this only causes a mild, short-lived burning sensation (https://en.wikipedia.org/wiki/Pholcidae#cite_note-12). I can go to sleep now. – Ivana Apr 12 '19 at 22:51
  • I am sorry for your son. Shame, the world needs a spidey IMHO! – Patrice Apr 13 '19 at 04:40
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    @delioth - the question asks if they can hurt. The answer is yes. And they would kill more in places like Australia if it wasn't for the antivenom. So the post directly answers the question. – Rory Alsop Apr 13 '19 at 09:05
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    @Rory I meant sorry he didnt develop powers ;) – Patrice Apr 13 '19 at 12:02
  • "Hurt" isn't the same as kill. It's reasonable to assume people consider a situation where their limb spells up painfully and they need to seek emergency medical treatment one where a spider hurt them, even if they don't die. Brown Recluse spiders in America cause severe tissue damage which I would certainly consider to fall under 'hurt'. Might be worth noting that in the UK, where Peppa Pig was originally broadcast, False Widows seems to only recently become somewhat common. When I was a child "spiders can't hurt you" was pretty much true. – Eric Nolan Sep 03 '21 at 09:36
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The claim

First let's start with noting that the goal of the episode was to get children over their irrational fear of spiders and making those children see the bigger picture.

Mummy says cobwebs mean spiders and she hates spiders but Daddy Pig doesn't because spiders eat flies and flies are horrid.

Source: Synopsis of episode https://peppapig.fandom.com/wiki/Spider_Web

And taking the claim "spiders are “very very small” and “can’t hurt you”" as a completely literal statement when it's from a show meant for children teaching vague general rules is not correct.

If we for example take a look at animal deaths in the US from 2008 to 2015 we find a lot more deaths due for example dogs than venomous spiders. Now imagine the same episode teaching children to not be afraid of dogs and whether a statement along the lines of "dogs are man's best friend" would be taken literally. It's of course not a 1:1 comparison at all, but the point is just to question whether the statement should be taken completely literally.

enter image description here

Source: wormsandgermsblog.com

Arachnophobia is the irrational fear of spiders (e.g. when my cousin literally was too afraid to pass under a bridge because there might be a spider hiding as there were some (old) cobwebs visible). This irrational fear is more common in children and adolescents and a claim like this needs to be understood in the context of trying to prevent and help people away from such phobias. Point is once again that the claim should be understood as an educational statement trying to help with a social problem.

People with phobia cause discomfort to others, and their behavior is socially unacceptable. Although individuals with phobia are aware that their fear is irrational,they cannot control their feelings. Therefore, a phobia is unquestionably a social dilemma

[...]

The initial age for animal phobia is usually 12 years old.One of the largest epidemiological studies in this field (n =43093) on specific fears was done in the United States and found that the highest prevalence of phobia was in children and adolescents.

Source: Entomophobia and Arachnophobia Among School-Age Children: A Psychological Approach

Important: This is not to say that this fully justifies such a claim as mild non-phobic fear/aversion of spiders you don't recognize is probably pretty healthy.

A literal interpretation of the claim

If we do take the claim literally than of course the table above does show that in the US there are just 6 fatalities per year due to venomous spiders ("just" compared to the danger of for example hornets, wasps and bees).

Looking at the home market of the show - the UK - the claim however is even literally pretty reasonable

How many UK spiders are actually dangerous?

Essentially, none.

There are three common spiders in the UK that are capable of biting you: the cellar spider, the woodlouse spider and the false widow spider. Their bites are painful and have been known to cause swelling for a few hours.

In 2014 a 60-year-old woman died after being bitten by a false widow spider. However, the cause of death was due to a bacterial infection from the puncture wound, rather than the spider venom itself.

Source: https://www.sciencefocus.com/nature/how-many-uk-spiders-are-actually-dangerous/

That doesn't mean nobody has an allergic reaction to a spider bites (or otherwise ends up with complications) or that spider bites never cause an infection (just like any scratch) which is why the anecdote in the highest voted answer is so misleading. It's the bigger picture (how common is something bad compared to how afraid people are) which explains why certain fears need to be addressed. In my personal opinion the show could have taken an even more nuanced tone (they suggest leaving them outside the house and not killing them which is already pretty reasonable).

David Mulder
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    Soo tempted to finish this answer with an anecdote as well, but must resist – David Mulder Apr 11 '19 at 13:44
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    I would like to add that most old world urban spider species are not dangerous for humans and may even be benefitial as they prey on other insects we consider more annoying (ie: mosquitoes). Peppa pig being a british series they may not though having to account for a place where any animal can kill you (aka: Australia). – Stormbolter Apr 11 '19 at 14:26
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    I'd say your average child under 10 has a hard time thinking any way other than literal. The exact message they will take is that "small" spiders are not dangerous. –  Apr 11 '19 at 17:29
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    Re: "Now imagine the same episode teaching children to not be afraid of dogs and whether a statement along the lines of 'dogs are man's best friend' would be taken literally": I would expect the episode to give basic advice about how to interact safely with dogs (e.g., don't pet a dog without the owner's say-so). – ruakh Apr 11 '19 at 20:09
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    @fredsbend I dunno, it often feels to me the opposite, nuance is something a child doesn't understand, everything seems quite black and white. Either you are afraid, or you're not afraid. The idea that you inspect the spider and then determine whether to be afraid of it is far too complex for a child. Even the idea that "don't be afraid, but don't touch or get close" is a very complex idea to get across. Starting with a "don't be afraid" sounds completely reasonable in most countries. – David Mulder Apr 12 '19 at 10:33
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    The problem is that how irrational the fear is varies by your location. Where I live black widows are moderately common and my wife was bitten by a spider that caused significant swelling and pain for days. I teach my youngest child to stay away from spiders and tell me if she sees one. I explain the nuances to my older children. I don't teach them to be afraid specifically, but I would rather have her be afraid then start getting close out of curiosity. – TimothyAWiseman Apr 12 '19 at 17:10
  • Comparing by number of deaths may not totally gauge their danger. Similar comments were made in response to [this comparison of animals](https://skeptics.stackexchange.com/a/17558/104) in response to another question (about whether Australian fauna is more dangerous). – Andrew Grimm Apr 27 '19 at 08:14
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Are spiders unable to hurt people?

There are several species of spiders, some large, others not so large. that are quite capable of harming people. Some can cause severe injury to or kill people. Three requirements:

  • The fangs need to be large enough to puncture the epidermis.
    The human epidermis is thick enough to render what otherwise would be harmful small creatures impotent with regard to humans.
  • The injected venom needs to be potentially harmful to people.
    Some spiders inject venoms that are very harmful to insects but have little impact on humans. But other spiders inject venoms that are potentially harmful to all animal life.
  • The amount of venom injected needs to be potentially harmful to people.
    A spider that injects a tiny amount of what would deadly venom in much larger amounts is not harmful. The dosage makes the venom venomous.

Some spiders pass all three requirements. People have died or lost appendages due to spider bites. Australia appears to be the worst place, but very venomous spiders do exist elsewhere. The Americas, for example, are home to several species of spiders that can be quite harmful to people, and even on occasion can kill. From Spider: This Bites: Venomous Texas Spiders,

The venom of the black widow is a neurotoxin and can lead to severe systemic reactions and in rare cases, death. The black widow's venom is reportedly 15 times more toxic than the venom of the prairie rattlesnake. However, only a minute quantity is injected with each bite.

and

Brown recluse spiders are golden brown in color and can be identified by the characteristic dark brown to black fiddle-shaped pattern on the head region. Brown recluse venom has necrotizing enzymes that generally cause local or systemic reactions.

Black widows are largish (but not huge) spiders, brown recluses, not so large.

Grimm The Opiner
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David Hammen
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    The hobo spider (sometimes called the fiddle-back spider) has been listed by the CDC along with the black widow and brown recluse as one of three venomous *and* dangerous spiders. They're not fully sure still on the hobo, so you'll find conflicting information. The hobo is pretty big too. –  Apr 11 '19 at 04:50
  • Also, the CDC seems to view causing dermonecrosis as the deciding factor on whether a certain spider's bite is dangerous. –  Apr 11 '19 at 04:59
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    Peppa Pig is British. [No spiders native to Britain can seriously injure people, almost none will attack people, and only a few of them have bites that can hurt.](https://www.animalwised.com/are-there-venomous-spiders-in-the-uk-1356.html) Therefore, the usual advice is to leave spiders alone. – reinierpost Apr 11 '19 at 09:42
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    @reinierpost The other answer has anecdata if someone getting a serious bite in Scotland (though it could be by an introduced species) https://skeptics.stackexchange.com/a/43770/104 – Andrew Grimm Apr 11 '19 at 12:26
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    Mmmm, necrotic tissue is definitely a serious injury. – reinierpost Apr 11 '19 at 12:30
  • "Australia appears to be the worst place" – Yakk Apr 11 '19 at 13:17
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    Small side note, there are no poisonous spiders, but [all spiders are venomous](https://hortnews.extension.iastate.edu/2008/12-10/spiderbites.html). – Jeff Lambert Apr 11 '19 at 14:06
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    @fredsbend Fiddleback is a nickname for the brown recluse, not the hobo spider. – Ray Apr 11 '19 at 17:50
  • @Ray Yes, you're right! I only added that because [I misread this link](https://www.orkin.com/other/spiders/hobo-spider-recluse) right before posting. I've only ever heard hobos called hobos. I thought it odd hobos would have that name, when it's the recluse that is called a fiddle spider because of the distinct fiddle shaped pattern *on its head*. I've never heard fiddleback before. I should have followed my better judgment. –  Apr 11 '19 at 18:05
  • @Yakk Do you think that needs a citation or is it such an obvious fact that no citation is required to substantiate the claim? – Michael Richardson Apr 11 '19 at 19:22
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    "Brown recluses, not so large". I believe an adult Brown Recluse is significantly larger than the black widow. Using U.S. money as a comparison, the Black Widow is slightly larger than a dime and a Brown Recluse can be larger than a quarter. The shiny black and red carapace of the Black Widow does make it much more visible though. – Michael Richardson Apr 11 '19 at 19:28
  • @michael I am just repeating it with context removed really. – Yakk Apr 11 '19 at 19:59
  • @fredsbend I just edited all the references of `poison` to `venom` ... That said, some spiders *might* be poisonous, but people eat them so rarely it's not a problem. :-) *That* said, I've seen that some rainforest tribey types catch and eat some large spiders... – Grimm The Opiner Apr 12 '19 at 07:24
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    @JeffLambert: “there are no poisonous spiders” — You can eat as many as you want! – Paul D. Waite Apr 12 '19 at 12:28
  • @JeffLambert From [Wikipedia](https://en.wikipedia.org/wiki/Spider#Feeding,_digestion_and_excretion): "Uniquely among chelicerates, the final sections of spiders' chelicerae are fangs, and the great majority of spiders can use them to inject venom into prey from venom glands in the roots of the chelicerae. **The families Uloboridae and Holarchaeidae, and some Liphistiidae spiders, have lost their venom glands, and kill their prey with silk instead.**" _(Emphasis mine.)_ – HABO Apr 12 '19 at 15:14
  • @HABO Good catch. I'm not personally an entomologist, I was just using the same words as one. I however didn't use couching language sufficiently as he did. – Jeff Lambert Apr 12 '19 at 15:18
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They are dangerous/harmful in more places than Australia

United States

Brown Recluse
enter image description here
Necrotic venom often requiring medical attention

Black Widow enter image description here
Female venom contains the neurotoxin latrotoxin.

Brazil

Banana Spider / Brazilian Wandering Spider enter image description here
One of the most venomous spiders in the world

Sri Lanka/India

Tarantula Poecilotheria enter image description here
Tarantuala with most potent venom

Africa

Six-Eyed Sand Spider enter image description here
Dermonecrotic venom, potentially life threatening

mcalex
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  • I hope these large images don't cause problems for arachnophobes. – Andrew Grimm Apr 27 '19 at 08:15
  • It's worth noting that Brown Recluse venom deadliness is a bit overstated. In most cases, it creates very localized necrosis that will heal without scarring within a few weeks. In rare cases, it's worse, but a lot of the "massive tissue damage" cases have actually been the result of doctors scooping out every bit of flesh that shows any irritation, combined with the effects of infection from all of that digging. – Sean Duggan Sep 02 '21 at 22:37