I’ve noticed that there are two kinds of responses people make when they learn I’m studying spiders. 1) They tell me about the terrible spider bites they’ve been getting lately, and 2) they ask if it’s true that people swallow thousands of spiders while sleeping in their lifetime. At least now I can cite this definitive response from Andrea Haberkern in answer to the first. Spiders have no interest in biting anyone!
Bite Post FAQs
1. Can anyone tell me what bit me?
Doctors nor entomologists nor arachnologists can ID bites from a bite alone in the majority of cases. There are likely a handful of exceptions, as in the case of some tick bites that have signs but overall this is not the case. So, if a someone tells you “it’s a spider bite” or “it’s a recluse bite” without seeing the animal itself do the biting, chances are it is something else entirely …but, more on that later…
2. What can we do about this bite?
First and foremost- this is a nature appreciation group, not a medical advice group. Medical advice is not allowed by any members. No members, to my knowledge, are medical doctors. If you or a loved one is suffering negative effects from a bite, please seek medical attention.
3. Do you think a spider bit me?
No. The reason for this is boils down to basic spider biology. I would venture to say that the vast majority of “spider bites” are something else entirely. I think many people believe that spiders go around biting sleeping people, falling from trees just to bite you or are sneaking around looking for their next tasty human to chomp on. I’m assuming the reason this is such a common misconception is likely due to a lack of understanding of what these animals are all about. So… spiders evolved venom to eat insects and other small prey. They use it to immobilize their prey. Just like it takes your body a tremendous amount of energy through food intake to conduct daily activities, it also costs spiders a lot of energy to produce this venom. Why would an animal that needs a substance to eat go around wasting it on mammals when it has nothing to gain for it? It wouldn’t. Now, I’m not saying spiders never bite. Any animal with a mouth can bite. If you grab a spider, I bet it will bite you- just like if you grab a squirrel it will bite you. But I don’t hear anyone saying squirrels are jumping into peoples’ beds while they sleep just to bite them. So why spiders? Spiders will bite in self-defense, but just to add to the unlikelihood of being bit by a spider- most species will do several other defense tactics before resorting to biting. These tactics include: fleeing, playing dead, threat displays, falling to the ground, kicking silk at you and, in some species, throwing poop at you. Biting is an absolute last resort, again because venom is energetically costly and its main purpose is to eat not defense, so you practically have to force a spider to bite you. Just to drive the point home even further- I would place money on the fact that I am likely one of the only people in here who has actually been bitten by a spider. But put that into perspective- I have to manhandle, harass and grab spiders, literally thousands of times, for my work…but even still- I’ve only been bitten a dozen or less times out of thousands of rough handling… I’ve deserved it every time. So, no, I don’t think a spider bit you. Even in cases where a spider was in the general vicinity… false blame is likely to blame.
4. So if a spider didn’t bite me what did?
There are literally hundreds if not thousands of other animals (and plants) that are more likely to have bit you or caused you skin irritations. These include anything that does either directly feed on us or uses bites/irritations as a defense. Examples of organisms that are a way more likely culprit for your skin issues include, but are not limited to: some midges, chiggers, mosquitoes, poison oak/poison ivy, horse flies, sand flies, fleas, stinging nettle, ticks, assassin bug defensive bites, conenose bugs, ant/bee/wasp stings and even some plant/fruit eating bugs that will take the occasional nibble.. etc. etc.
5. But but but I saw 2 puncture holes in my skin, it had to be a spider….
This is a myth. I think it comes from a common misunderstanding of spider mouthparts. Most people assume that all spider chelicerae (fangs) face downward like that of a tarantula and therefore cause 2 bite marks. This is not the case. Only the Mygalomorphs (tarantulas, trapdoor spiders and Aussie funnelwebs) have their mouthparts oriented like this. But seeing that tarantulas and kin are much larger spiders- I think you would physically see if one bit you. So, when someone says “I know this much smaller spider bit me even though I didn’t see the spider because I have 2 bite marks” … there several reasons why this is not the case. First, most spiders’ mouthparts are oriented to meet side to side not parallel facing downward (if the visual is too hard to imagine google image search “Mygalomorph versus Araneomorph mouthparts”) So, if one bit you, a single puncture would be more likely from where the 2 fangs meet. Next, if there were 2 bite marks in the skin caused by a spider- this would have to be a BIG spider for them to even be visible- I highly doubt a spider of that size is capable of sneaking in, biting you without you seeing it, then sneaking away in the night to leave you with only 2 little vampire marks as “proof”. Many many insects will bite multiple times in a localized manner, and considering how much more likely insects are to bite humans than spiders in the first place, that again is more likely your little biting friend.
As for the second question…no spider would blithely crawl into a large carnivore’s mouth. Do you also think hippopotamuses lounge about complaining about all the humans who wandered into their gullets while they were sleeping? No. The whole idea is nonsense, and I’d really like to know where that myth started. I’ve been surprised at how many people ask me if it’s true that people swallow 8 (or some other number) spiders a night, when only a moment’s thought would tell you it’s absurd.
P.S. I’ve never been bitten by a spider, but then I only work with little house spiders. They’ve also never leapt into my mouth.