Latest / Spooky Season Podcasts 🎃 / This Podcast Will Kill You: Ep 219 The Brown Recluse: Fearsome foe or slandered spider?
Transcript
- 0:00Speaker 1: Missus CS, aged twenty four, entered the hospital because of
- 0:03Speaker 1: a spider bite on the ulnar side of the right
- 0:05Speaker 1: elbow and a rash over the entire body, with the
- 0:08Speaker 1: exception of the face. She stated that while riding in
- 0:11Speaker 1: an automobile November fifth, nineteen twenty eight, she suddenly felt
- 0:15Speaker 1: a sticking sensation on her right elbow. She removed her coat,
- 0:18Speaker 1: ran her hand into the sleeve, and withdrew a small object,
- 0:21Speaker 1: which dropped to the floor of the car and which
- 0:24Speaker 1: when recovered, was found to be a rather small taan spider.
- 0:28Speaker 1: Her arm began to pain at once, the pain becoming
- 0:31Speaker 1: progressively worse. On returning home an hour later, she examined
- 0:35Speaker 1: her arm and found a dark red spot surrounded by
- 0:38Speaker 1: an area of pallor. She slept well until three am
- 0:41Speaker 1: without a sedative, when she awakened with pain in her
- 0:44Speaker 1: right arm and a generalized rash which was most pronounced
- 0:47Speaker 1: on the abdomen and back. Her arm at this time
- 0:50Speaker 1: was aching and had swollen somewhat. The next day, the
- 0:54Speaker 1: swelling was very pronounced. Four days later, the rash seemed
- 0:57Speaker 1: to be fading, but the following day it was as
- 0:59Speaker 1: bad before. Before entering the hospital. The patient had a
- 1:03Speaker 1: rapid pulse, but her temperature reaction was mild, never much
- 1:06Speaker 1: over one hundred degrees fahrenheit. She entered the hospital five
- 1:10Speaker 1: days after having been bitten. The patient was anxious and restless.
- 1:14Speaker 1: The arms, legs, abdomen, and chest were covered with a
- 1:16Speaker 1: scarletiniform rash with a few small pustules on the legs.
- 1:20Speaker 1: On the inner surface of the right elbow was found
- 1:22Speaker 1: a small reddened area with a yellow center resembling a
- 1:26Speaker 1: small pustule. The area around the elbow was swollen and tender.
- 1:30Speaker 1: The entire abrasion was not more than one fourth inch
- 1:32Speaker 1: in diameter.
- 1:33Speaker 2: The treatment was.
- 1:34Speaker 1: Essentially palliative, consisting of sedatives internally and starch and sodium
- 1:38Speaker 1: bicarbonate baths. A solution of point five percent lead acetate
- 1:42Speaker 1: was used in wet packs applied to the area of
- 1:44Speaker 1: the bite. The spider was identified by Professor C. R.
- 1:47Speaker 1: Crosby of Cornell University as the specimens of Loxicele's refessens,
- 1:52Speaker 1: a species usually found in Texas, Florida, Mexico, Costa Rica, Europe,
- 1:56Speaker 1: and Japan. As Yet, little reference has been made in
- 1:58Speaker 1: the literature regarding its toxicity. So far as my search
- 2:01Speaker 1: of the literature enables me to judge, no case of
- 2:04Speaker 1: poisoning from its bite has been reported from this region.
- 2:53Speaker 2: Well well, well, well, well, well how about it?
- 2:58Speaker 1: How about that.
- 3:01Speaker 2: That was excerpted from a paper in nineteen twenty nine
- 3:06Speaker 2: by the by a doctor lf Schmouse and it's called
- 3:12Speaker 2: case of a rachnoidism spider bite, spider bite in jama
- 3:16Speaker 2: And this is what a lot of papers point to
- 3:18Speaker 2: as the first likely reported scientific clinical case study of
- 3:24Speaker 2: a bite from a brown recluse. And if you are
- 3:27Speaker 2: a spider nerd and you heard the scientific name in
- 3:31Speaker 2: the first hand locks of Cell's refesseens, that I think
- 3:34Speaker 2: is what it initially was called before they changed it
- 3:36Speaker 2: to reclusa. I don't know the timeline.
- 3:39Speaker 1: There's also there's another species that's like the Mediterranean recluse
- 3:43Speaker 1: that's like refusines now today, So like who knows which
- 3:47Speaker 1: species it actually was at the time, but right they're similar.
- 3:50Speaker 2: But yeah, yeah, there you go. So we go. Hi.
- 3:54Speaker 2: I'm Aaron Welsh and I'm Erin alman Updite and this
- 3:57Speaker 2: is this podcast will kill you.
- 3:59Speaker 1: Today we're talking brown recluse bites. We are I'm really
- 4:05Speaker 1: excited about this.
- 4:06Speaker 2: Actually you too. It's so interesting how large the fear
- 4:13Speaker 2: looms in many places and infamous I think is like
- 4:19Speaker 2: that's a correct I think, yeah, that's a correct and
- 4:21Speaker 2: like I can't wait to tell everyone how undeserved the infamy. Really. Yes,
- 4:26Speaker 2: we're going to dispel some myths here. We're going to
- 4:29Speaker 2: try to do a little bit of like reputational rehab
- 4:31Speaker 2: for these spiders, but also acknowledge that, like you know,
- 4:35Speaker 2: they as you will learn, the bite can be quite.
- 4:39Speaker 1: It can be bad. Yeah, it can be bad.
- 4:41Speaker 2: But there's a lot to cover. So you're excited. We
- 4:44Speaker 2: should finish our intro exactly.
- 4:48Speaker 1: First up, it's quarantin any time.
- 4:50Speaker 2: It is this week we are drinking a tangled web,
- 4:54Speaker 2: A tangled web. Yeah it is. Hold on, I wrote
- 4:57Speaker 2: in my notes because we picked this out cherry juice,
- 4:59Speaker 2: limed soda, water and marish, you know, cherry syrup.
- 5:03Speaker 1: A little bit reddish, a little bit bloody maybe.
- 5:06Speaker 2: Sure, sure, Yeah, it's delicious, it's refreshing, you know.
- 5:11Speaker 1: Check it out the full recipe on our website, This
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- 5:39Speaker 1: Rate, review, and subscribe. We'd like to remind you. Shall
- 5:43Speaker 1: we get into this.
- 5:44Speaker 2: Let's do it after this quick break.
- 5:59Speaker 1: So to episode is not about all spiders by any means,
- 6:05Speaker 1: because spiders are incredibly varied. There are somewhere between forty
- 6:10Speaker 1: and fifty thousand species that we know of, and probably
- 6:13Speaker 1: another ninety thousand species we have yet to discover or name,
- 6:17Speaker 1: and they exist in every ecosystem on the planet except
- 6:20Speaker 1: for Antarctica, etc.
- 6:23Speaker 2: But what we are.
- 6:24Speaker 1: Talking about today is one specific spider, which is the
- 6:29Speaker 1: brown recluse loxo Cell's reclusa. Now, this is one of
- 6:36Speaker 1: a handful, literally just a handful of spiders that are
- 6:40Speaker 1: considered medically important. In fact, there are at least one
- 6:44Speaker 1: hundred related species of lox of cells. Many of the
- 6:48Speaker 1: venoms of these different los oficell species all act very similar.
- 6:52Speaker 1: So I'm going to focus on the brown recluse today.
- 6:55Speaker 1: Because this is like one of the most infamous spiders
- 6:57Speaker 1: aside from the black widow black widow, which I couldn't
- 7:02Speaker 1: remember the name of real quick in the US. I
- 7:04Speaker 1: feel like the black widow is like the most famous,
- 7:07Speaker 1: and then the brown recluse is also the most famous.
- 7:10Speaker 1: I feel like they're equal. Sure, I don't know, I
- 7:13Speaker 1: have no I don't have a statistic on that. Yeah,
- 7:17Speaker 1: but the brown recluse is actually not found in very
- 7:19Speaker 1: much of this country. It's really only found across the
- 7:22Speaker 1: south central US, from like the lower Midwest, like halfway
- 7:26Speaker 1: through Illinois and then down into the Gulf. It goes
- 7:30Speaker 1: as far east as like Tennessee and then as far
- 7:34Speaker 1: west as like just to the edge of Texas.
- 7:37Speaker 2: Kind of yeah, it's like not quite in Colorado, for example,
- 7:41Speaker 2: the very.
- 7:41Speaker 1: Edge not coldo. It's not here in California. There are
- 7:46Speaker 1: a few other species in the US. One that is
- 7:49Speaker 1: called blocks of Cell's deserta that is in like Arizona,
- 7:52Speaker 1: New Mexico and a little bit of California. And there
- 7:56Speaker 1: are a number of other species of again medical importance
- 7:59Speaker 1: throughout Central and South America, including Locoicelli's intermedia gaucho, Latia
- 8:05Speaker 1: and refusins, which is actually the Mediterranean spider that has
- 8:08Speaker 1: been invasive in a number of areas as well. So
- 8:12Speaker 1: all of these recluse species are these kind of smallish
- 8:18Speaker 1: brown spiders. There may be like one to two centimeters
- 8:22Speaker 1: in total including their legs. Some of the older ones
- 8:25Speaker 1: could get up to like three centimeters, so they're really
- 8:27Speaker 1: not large.
- 8:28Speaker 2: That's very small.
- 8:29Speaker 1: Yeah, yeah, I think we're going to have to find
- 8:32Speaker 1: some pictures to post of these two, so we will,
- 8:34Speaker 1: we will. But their legs are very long and slender,
- 8:40Speaker 1: and they don't have one of those real globe like
- 8:43Speaker 1: abdomens that we see in black widows. Their abdomen is
- 8:46Speaker 1: a bit more elongated, and their whole body, the cephalothorax,
- 8:50Speaker 1: the top part and the abdomen. They're quite a bit
- 8:53Speaker 1: flatter than other, like real hefty looking spiders, and they
- 8:58Speaker 1: tend to sit with their legs quite outright. They're not
- 9:02Speaker 1: all bent up, and that's because they like to hide
- 9:05Speaker 1: in teeny tiny little cracks and crevices, So they're really
- 9:08Speaker 1: a flatter spider than some big like you know.
- 9:11Speaker 2: Right tarantula looking right exact.
- 9:16Speaker 1: They can vary in color from a like lightish yellowy
- 9:19Speaker 1: brown to almost a gray, or as they get older
- 9:24Speaker 1: they darken, which I think is really interesting, so they
- 9:26Speaker 1: can be quite dark brown if they're an older spider.
- 9:30Speaker 2: Yeah, and they're.
- 9:31Speaker 1: Very famous for having this so called violin pattern on
- 9:35Speaker 1: their cephalothorax or fiddle or a fiddle, a violin or
- 9:39Speaker 1: a fiddle, so they're often called violin or fiddleback spiders.
- 9:42Speaker 1: I don't see a violin as hard as I try
- 9:44Speaker 1: in theory. It's like the neck of the violin points
- 9:47Speaker 1: towards their abdomen and the body of it is towards
- 9:49Speaker 1: their head. I don't think it looks like a violin
- 9:52Speaker 1: at all. And there's plenty of other spiders that have
- 9:56Speaker 1: similar like violin patterns, so really that's not a good
- 9:58Speaker 1: way to identify them. What is a good way to
- 10:01Speaker 1: identify them is that number one, their abdomen and their
- 10:07Speaker 1: legs are one color. They don't have patterns on their
- 10:10Speaker 1: abdomen or on their legs. So if you see a
- 10:13Speaker 1: spider that has a pattern on their belly or their
- 10:16Speaker 1: legs have speckles and splotches, that's not a round reckless.
- 10:20Speaker 1: And they have six eyes.
- 10:23Speaker 2: I have that as a fun fact.
- 10:25Speaker 1: So fun and they're arranged in three pairs, so they
- 10:28Speaker 1: have these two in the middle and then two on
- 10:30Speaker 1: either side. Is kind of cute and ridiculous sleeping, and
- 10:34Speaker 1: so that's how you can kind of identify them. They
- 10:37Speaker 1: make webs like pretty much most spiders, but they don't
- 10:40Speaker 1: make those beautiful like Charlotte's Web kind of webs like
- 10:45Speaker 1: or Siker type or weaverery types. In fact, they make
- 10:48Speaker 1: these really tangled, mish mush sheet webs that they use
- 10:53Speaker 1: to just kind of cover little cracks in bark or
- 10:56Speaker 1: under rocks or holes in the ground or maybe in
- 10:59Speaker 1: a pie of lumber in your backyard or bookshelf or
- 11:05Speaker 1: in your basement, whatever it is, and they can live
- 11:08Speaker 1: for a number of years.
- 11:11Speaker 2: That's another of my fun vats to talk about.
- 11:16Speaker 1: I won't say anything more.
- 11:17Speaker 2: Okay, no, no, it's okay, you can keep going.
- 11:20Speaker 1: That's not literally all I have arin that's the spiders themselves. Okay.
- 11:24Speaker 1: So the most important thing about spiders for humans is
- 11:29Speaker 1: that they make venom. All spiders make venom. And the
- 11:34Speaker 1: last time that we talked about venom was in our
- 11:36Speaker 1: Snake Venom episode.
- 11:38Speaker 2: Wow, yeah, a really long time ago to venoms.
- 11:41Speaker 1: I know, and to distinguish a venom from a poison,
- 11:46Speaker 1: which I feel like is important. A poison is a
- 11:49Speaker 1: toxic substance that's produced in nature, so by a plant
- 11:52Speaker 1: or an animal that usually can produce symptoms via any
- 11:56Speaker 1: kind of contact, so contact with mucus membranes or via ingestion,
- 12:00Speaker 1: whereas a venom is a specific type of poison that
- 12:04Speaker 1: is delivered via this specialized system where it has to
- 12:06Speaker 1: be injected. Okay, most venoms are used either for prey
- 12:11Speaker 1: capture or as self defense. Yeah, and while all spiders
- 12:17Speaker 1: have venom, and venoms are by no means unique to
- 12:20Speaker 1: spiders or even arthropod's, lots of animals make venoms. Spider
- 12:25Speaker 1: venom is really interesting because it can vary really widely
- 12:29Speaker 1: across the spiders all spiders, but in all of them,
- 12:33Speaker 1: they're housed in this specialized pair of appendages called the chiliserae,
- 12:37Speaker 1: which I think are very cute, and they're basically they
- 12:42Speaker 1: they I think people think of them as the fangs
- 12:45Speaker 1: because it's what sticks out from a spider's little face.
- 12:48Speaker 1: But if you think of like your hand as the
- 12:50Speaker 1: actual chilisra, and then your fingers are the fangs, fangs
- 12:54Speaker 1: sit tucked up underneath their chillisserae, and then the venom
- 12:57Speaker 1: glands are located in the chilisrae.
- 13:00Speaker 2: They have a duct that.
- 13:02Speaker 1: Goes down to the tip of the fang, and they're
- 13:05Speaker 1: surrounded by muscles and nerves, So the spider can actually
- 13:07Speaker 1: control how much venom it releases with each bite, or
- 13:11Speaker 1: whether it releases any venom at all.
- 13:15Speaker 2: Interesting mm hm.
- 13:17Speaker 1: And so basically, when a spider is ready to it
- 13:19Speaker 1: flicks its things out and then stabs them in and
- 13:22Speaker 1: then releases whatever type, whatever mixture of whatever amount of
- 13:26Speaker 1: venom they decide to do.
- 13:28Speaker 2: What are the things made of? Oh, I don't know.
- 13:33Speaker 2: Kit I don't know, I know, just like is it
- 13:35Speaker 2: specialized kiten? Like why, you know, how do they actually
- 13:39Speaker 2: penetrate human skin for instance, or you know, does it?
- 13:43Speaker 1: And yeah, that's a great question. I don't know. I
- 13:47Speaker 1: didn't look that much into detail of it. Most, I mean,
- 13:49Speaker 1: spider exoskeletons in general and made of mostly kiten, so
- 13:52Speaker 1: I imagine it's just like a specialized extra hard in kiten.
- 13:55Speaker 1: They do have to be large enough in diameter and
- 13:58Speaker 1: sharp enough to be able to penetrate human skin. Most spiders.
- 14:01Speaker 1: Their fangs are not sharp enough or large enough to
- 14:03Speaker 1: penetrate human skin.
- 14:04Speaker 2: Which is it is? And this is where I didn't
- 14:06Speaker 2: even get in. I didn't look into this at all.
- 14:08Speaker 2: But it's it's interesting to think about, like brown recluse
- 14:11Speaker 2: spiders being quite little. Yes, why why do they have
- 14:15Speaker 2: fangs that are capable can do that?
- 14:17Speaker 1: Yeah? It is interesting. Yeah, I don't have an answer
- 14:19Speaker 1: for that. Little little beetbops. I mean, black widows are
- 14:22Speaker 1: real small too, Yeah they are. Yeah, so I don't know, huh.
- 14:27Speaker 2: But then similarly sized or larger spiders don't.
- 14:30Speaker 1: Don't necessarily yes, or maybe their venom is just not as.
- 14:34Speaker 2: Part their venom is not as poet right, I mean,
- 14:37Speaker 2: can penetrate spider bites? Yeah?
- 14:38Speaker 1: Yeah, So let's talk about the venom of the brown recluse,
- 14:42Speaker 1: shall we.
- 14:43Speaker 2: Let's do it.
- 14:44Speaker 1: It is a lot like there are a lot of
- 14:48Speaker 1: different enzymes contained in this venom. It is not just
- 14:51Speaker 1: one thing, but the most important of which we think
- 14:55Speaker 1: for human like the kinds of symptoms that we see
- 14:58Speaker 1: from a human bite is called sphingle myelinase D, which
- 15:03Speaker 1: is just one type of enzyme. But what it does
- 15:06Speaker 1: is it attaches to our cell membranes, especially on our
- 15:09Speaker 1: red blood cells, but also on our endothelial cells, so
- 15:14Speaker 1: that's the cells that line our blood vessels and lots
- 15:16Speaker 1: of other cells kind of indiscriminately. And what it does
- 15:19Speaker 1: is disintegrate these cell membranes, so it causes our cells
- 15:23Speaker 1: to lice and break open. That not great, and that
- 15:28Speaker 1: in our body is going to cause the release of
- 15:30Speaker 1: a huge amount of inflammatory markers. Right, It's going to
- 15:33Speaker 1: stimulate our immune system because we're like, why are our
- 15:36Speaker 1: cells breaking open. It's also going to trigger our clotting cascade,
- 15:41Speaker 1: which see our hemophilia episode for all the details on.
- 15:45Speaker 2: That four or five years ago.
- 15:47Speaker 1: Who knows lost is not more? And so what this
- 15:50Speaker 1: means is that things like our red blood cells are
- 15:53Speaker 1: being hemalized, they're breaking open, the stuff that's in our
- 15:56Speaker 1: red blood cells are spilling out, and our clotting cascade
- 16:01Speaker 1: is being activated. And so this can cause both bleeding
- 16:06Speaker 1: and a coagulopathy, so blood clots that can form. So
- 16:10Speaker 1: then what we can see is surrounding the area of
- 16:14Speaker 1: the bite where this venom has penetrated, we can see
- 16:16Speaker 1: tissue death or necrosis. And as this venom diffuses through
- 16:20Speaker 1: our bloodstream. We can see more serious symptoms depending on
- 16:24Speaker 1: kind of how far it goes and how rampant the
- 16:27Speaker 1: immune response really is.
- 16:29Speaker 2: And does that depend on location of bite. It's such
- 16:33Speaker 2: a good question.
- 16:34Speaker 1: It probably depends on a lot of different things, the
- 16:37Speaker 1: location of the bite, how much venom was injected, or
- 16:40Speaker 1: whether venom was injected at all. And I tried to
- 16:42Speaker 1: get a sense of like how much venom does a
- 16:44Speaker 1: spider bite give you? And I couldn't. I don't know
- 16:48Speaker 1: if you found that anywhere. I found one paper that
- 16:51Speaker 1: said that the approximate amount of venom per bite was
- 16:53Speaker 1: two thousand nanograms, but the citation on that was like
- 16:56Speaker 1: a personal communication with some dude who raises spiders.
- 17:00Speaker 2: Also, like that number has no meaning, It has.
- 17:02Speaker 1: No meaning, exactly like how many millileaters?
- 17:05Speaker 2: I have no idea.
- 17:06Speaker 1: It's a very very small amount, right, this is a
- 17:09Speaker 1: teeny spider. It's injecting a very small amount, but it's
- 17:11Speaker 1: very potent venom, right, So it's going to depend probably
- 17:14Speaker 1: on the amount, on the location, on the age of
- 17:18Speaker 1: the person. So kids seem to be more adversely affected
- 17:21Speaker 1: than adults when they get bitten, And then probably other
- 17:25Speaker 1: things too, especially when we talk more about the symptoms.
- 17:27Speaker 1: If you have something like diabetes, that's going to delay
- 17:30Speaker 1: your wound healing to begin with. Right, So there's going
- 17:32Speaker 1: to be a lot of individual factors that play into
- 17:34Speaker 1: how bad this bite ends up being. And the thing
- 17:38Speaker 1: is that as scary as that venom sounds, right, this
- 17:40Speaker 1: venom is diffusing into your skin and blood vessels and
- 17:45Speaker 1: disintegrating cells as it goes. It sounds pretty bad.
- 17:48Speaker 2: I just leave in a trail of destruction. Right.
- 17:52Speaker 1: You are so unlikely to be exposed to this venom, right, Yeah?
- 17:57Speaker 1: Because first of all, these spiders are nocturnal. They're not
- 18:00Speaker 1: out and about wandering around when we are. They're holed
- 18:04Speaker 1: up in teeny tiny cracks and crevices. They are not
- 18:08Speaker 1: aggressive spiders.
- 18:10Speaker 2: They're really not. These are reclose for a reason.
- 18:13Speaker 1: Right, They are really not aggressive. Like there are spiders
- 18:15Speaker 1: in Australia that will chase you around the room or
- 18:18Speaker 1: like rear up and attack you, and these spiders really don't.
- 18:22Speaker 1: They really really try to avoid contact with you, and
- 18:26Speaker 1: they will bite you if they are, for example, wrapped
- 18:29Speaker 1: up in your summer towels that you finally take out
- 18:32Speaker 1: and then wrap yourself around in and they get squished
- 18:35Speaker 1: between you and a towel. Those are the kinds of
- 18:37Speaker 1: situations that they bite with in. Yeah, but despite their
- 18:42Speaker 1: quiet nature, their venom can pack quite a punch, so
- 18:46Speaker 1: it's often called necrotic aracnetism or gangreno cutaneous aracnism, or
- 18:53Speaker 1: even lucks of sellism. Yeah, I've seen that a lot
- 18:56Speaker 1: when you get envenomated by a brown recluse, And most
- 19:01Speaker 1: of the literature kind of splits the array of symptoms
- 19:04Speaker 1: that we can have into four kind of categories. One
- 19:08Speaker 1: is no symptoms at all, One is minor injury. I
- 19:12Speaker 1: guess that's number two. Three is like a slightly worse
- 19:16Speaker 1: skin lesion that may leave a scar. And then finally
- 19:20Speaker 1: you can have systemic symptoms. So we can kind of
- 19:22Speaker 1: go through all of those. Often the bite itself is
- 19:26Speaker 1: not necessarily painful, which can mean that it's hard to
- 19:29Speaker 1: know right away if you got bitten. You don't necessarily
- 19:32Speaker 1: feel the moment that those fangs puncture your skin. But
- 19:36Speaker 1: usually within a few hours of a bite, you might
- 19:38Speaker 1: see redness or swelling, and you might have a kind
- 19:42Speaker 1: of burning pain or itching, not dissimilar to any other
- 19:46Speaker 1: insect bite. Really and then at some time over the
- 19:50Speaker 1: next few hours or couple of days, you might see
- 19:54Speaker 1: a central area of kind of necrotic tissue or this
- 19:58Speaker 1: dead kind of tissue that starts to deve. It might
- 20:01Speaker 1: look just like a kind of duskier color that doesn't
- 20:06Speaker 1: necessarily look like dead skin. It's just sort of like
- 20:08Speaker 1: a duskier color with like a reddish ring around it.
- 20:12Speaker 1: Or it could look like kind of a blood blister
- 20:14Speaker 1: in the center.
- 20:15Speaker 2: These are all googleable pictures if you would like to see
- 20:18Speaker 2: for yourself.
- 20:19Speaker 1: Just although so many pictures on Google are like, probably
- 20:22Speaker 1: not actually a brown recluse bite.
- 20:24Speaker 2: Wow, yeah, that is also the story of brown recluse.
- 20:28Speaker 1: And then this can progress to basically like a necrotic
- 20:32Speaker 1: area of tissue that's usually really well defined and then
- 20:36Speaker 1: surrounded by redness, which depending on the area, could spread
- 20:39Speaker 1: like a good ways up say your arm or something,
- 20:42Speaker 1: over the course of a few days, or it might
- 20:44Speaker 1: just be right around where that wound is. And even
- 20:48Speaker 1: though this can result in an ulcer that eventually kind
- 20:51Speaker 1: of sluffs off and takes quite some time to heal,
- 20:56Speaker 1: it generally will heal on its own even without any
- 21:00Speaker 1: major medical interventions and I think it's easy for us
- 21:03Speaker 1: to hear the word necrotic tissue and think that's really bad,
- 21:06Speaker 1: I'm going to need surgery, et cetera. But it's usually
- 21:08Speaker 1: just the first couple of layers of skin and that
- 21:11Speaker 1: like a little bit of dermis that gets affected, and
- 21:14Speaker 1: so this usually heals completely on its own.
- 21:16Speaker 2: It's interesting. I was going to ask about, like, which proportion,
- 21:20Speaker 2: you know, how do all bites fall into these different
- 21:23Speaker 2: categories of no, you know, minor symptoms, et cetera. But
- 21:28Speaker 2: I would imagine that it's really difficult to get accurate
- 21:30Speaker 2: numbers given how many bites are misdiagnosed or how many
- 21:35Speaker 2: you know, wounds are misdiagnosed as brown recluse bites.
- 21:38Speaker 1: Yes, the number that I saw over and over in
- 21:40Speaker 1: the literature. And I don't know how they came up
- 21:42Speaker 1: with this, but they said that ninety percent of the
- 21:44Speaker 1: time there's like no need for medical intervention at all.
- 21:47Speaker 2: So it's only ten.
- 21:48Speaker 1: Percent of the time that a bite from a brown
- 21:50Speaker 1: recluse would need some kind of medical intervention. And even
- 21:52Speaker 1: that doesn't necessarily mean it's severe. It might just mean
- 21:54Speaker 1: wound care. Right, Yeah, there can be more systemic symptoms
- 21:58Speaker 1: like was described in our stand account. This like generalized rash,
- 22:03Speaker 1: This like red, splotchy, little little bumpy kind of rash
- 22:07Speaker 1: that almost looks like an allergic reaction or something. Even
- 22:11Speaker 1: that is usually self limited, so even that you usually
- 22:14Speaker 1: don't necessarily need to seek medical care or people don't
- 22:16Speaker 1: need a lot of medical intervention. However, there can be
- 22:20Speaker 1: more severe systemic symptoms from a brown recluse bite. As
- 22:25Speaker 1: this venom diffuses through the bloodstream and causes this immune
- 22:28Speaker 1: system activation and the hemolysis, the breaking open of our
- 22:31Speaker 1: red blood cells. We can start to see signs like fevers, chills, nausea,
- 22:37Speaker 1: or vomiting. People might show signs like jaundice and dark urine,
- 22:42Speaker 1: which means like massive level hemolysis or red blood cells
- 22:45Speaker 1: breaking open, and that eventually can lead to renal damage,
- 22:49Speaker 1: so kidney failure, even cardiovascular failure like edema in your
- 22:54Speaker 1: lungs which makes it really hard to breathe, and this
- 22:58Speaker 1: can In the literature it says lead to death. However,
- 23:03Speaker 1: as it we don't really know. Because there were eight
- 23:08Speaker 1: reported deaths in the US that were attributed to brown
- 23:11Speaker 1: recluse bites between nineteen eighty three and two thousand and four.
- 23:15Speaker 1: None of these were actually confirmed by spider identification. Okay,
- 23:22Speaker 1: there are reports in the literature of brown recluse bites
- 23:25Speaker 1: being fatal, but I couldn't find any that were like,
- 23:29Speaker 1: really really confirmed that there was a brown recluse. Either
- 23:33Speaker 1: we saw a bite or there was a spider recovered
- 23:35Speaker 1: shortly after these symptoms started, and that spider was identified
- 23:38Speaker 1: to be a brown recluse. Right, So it's a little
- 23:41Speaker 1: unclear if those systemic symptoms really were from a brown
- 23:45Speaker 1: recluse bite or not. And that's the thing that makes
- 23:47Speaker 1: this so hard. Yeah, it's really hard to definitively diagnose
- 23:53Speaker 1: a brown recluse.
- 23:53Speaker 2: Bite or any kind of spider bite, any spider bite
- 23:57Speaker 2: without having and like, you want to make the right diagnosis, right,
- 24:02Speaker 2: but how do you do that?
- 24:03Speaker 1: How do you do that? And technically to actually diagnose
- 24:07Speaker 1: a spider bite properly, you have to save the spider,
- 24:10Speaker 1: So you have to have the spider with you. That
- 24:12Speaker 1: spider needs to be identified by somebody who actually has
- 24:15Speaker 1: some degree of expertise in identifying spiders, because us as
- 24:18Speaker 1: the general public are really not good at it. There's
- 24:20Speaker 1: some interesting papers about people sending in brown recluses. Most
- 24:24Speaker 1: of them are not brown recluses, And a lot of
- 24:27Speaker 1: times you might not feel the bite initially, So if
- 24:29Speaker 1: you didn't witness the spider bite, or if you didn't
- 24:32Speaker 1: find a spider very close to you, or like in
- 24:35Speaker 1: your bed when you woke up with a bite or
- 24:37Speaker 1: something like that, it's really hard to directly connect those
- 24:42Speaker 1: two things. And there are so many other conditions that
- 24:47Speaker 1: can mimic.
- 24:48Speaker 2: These bites, my gosh, so many.
- 24:49Speaker 1: A staph infection, a strep infection, cutaneous anthrax, a vasculitis,
- 24:53Speaker 1: some kinds of cancers, atypical mycobacterial infections, diabetic ulcers, septic emboli,
- 25:00Speaker 1: other bites, and venom stings from other kinds of insects.
- 25:04Speaker 1: The list really does go on. And brown recluses are
- 25:08Speaker 1: not ubiquitous across this country, so they're often diagnosed in
- 25:13Speaker 1: areas that they don't even actually exist, which is wild
- 25:17Speaker 1: to me. Yeah, but because we don't learn the distribution
- 25:20Speaker 1: of spider species in med school, so just.
- 25:23Speaker 2: Right, you just learn about brown recluse bite.
- 25:25Speaker 1: Bron recluse bite. And so you see a thing and
- 25:27Speaker 1: you're like, and someone comes in and says, I think
- 25:29Speaker 1: this was a spider brighte spider bite. Yeah, right, so
- 25:33Speaker 1: it's they're really hard to diagnose. We also don't have
- 25:35Speaker 1: any like specific treatment or any specific diagnostics to be like,
- 25:38Speaker 1: can I identify brown recluse venom in your blood? We
- 25:41Speaker 1: don't have that. Yeah, And there's really no consensus on
- 25:44Speaker 1: how we actually treat this, so it's really just depending
- 25:47Speaker 1: on what someone's symptoms are what you're going to do
- 25:50Speaker 1: to treat it, which I think is interesting too.
- 25:53Speaker 2: Okay, let's say that you have some sort of necrotic
- 25:56Speaker 2: skin lesion. Does your course of treatment differ based on
- 26:01Speaker 2: whether that's caused by a spider bite versus something else?
- 26:03Speaker 2: I mean, yes, it could, but like it is kind
- 26:07Speaker 2: of interesting, like how I don't know, like does does
- 26:10Speaker 2: it right? When? When would you? I mean maybe if
- 26:13Speaker 2: it's like Mercy, you're using antibiotics and stuff exactly.
- 26:15Speaker 1: But like I think that's the biggest thing, is like
- 26:18Speaker 1: whether we need to use antibiotics If it's just a
- 26:19Speaker 1: spider bite, you probably don't, but it might really look
- 26:22Speaker 1: like something that you would want to use antibiotics for.
- 26:25Speaker 1: So it is it is it's one of those that
- 26:27Speaker 1: just is going to need monitoring, right right, right.
- 26:31Speaker 2: Did you say anything about immunity. I did not, did
- 26:35Speaker 2: you I did? I mean only minorly, And I don't
- 26:39Speaker 2: know if I actually wrote it down anywhere. But there
- 26:41Speaker 2: was a study that looked at exposure to like of
- 26:45Speaker 2: rabbits to spider bites, multiple spider bites. Okay, so they
- 26:48Speaker 2: did say, like, okay, yes, this can kill a rabbit.
- 26:51Speaker 1: Yes, but I have a lot of good animal studies
- 26:53Speaker 1: on the effects of the venom in animals.
- 26:56Speaker 2: Yeah, but then they also said that those rabbits that
- 26:58Speaker 2: did not die from this bite then re exposed tended
- 27:01Speaker 2: to have less severe reactions. Oh, that's so interesting. It
- 27:05Speaker 2: was also like it was not I don't think. I
- 27:06Speaker 2: don't think this was a recent paper, and I don't
- 27:08Speaker 2: think this was like a super It was just sort
- 27:10Speaker 2: of like disgusted. So I don't know the degree of
- 27:14Speaker 2: immunity or like whether that was demonstrated clearly or just suggested.
- 27:19Speaker 1: That's so interesting. Yeah, well, Aaron, that's brown recluses. Can
- 27:24Speaker 1: you tell me about these spiders and our long I
- 27:29Speaker 1: assume it's a long history with these although.
- 27:31Speaker 2: I don't know what is it. You know, that's a
- 27:34Speaker 2: great question. Okay, let's let's see what we can find out.
- 27:53Speaker 2: Brown reckless fighters, like we said, are infamous. They are
- 27:57Speaker 2: widely feared, they are hated, even I would say there
- 28:01Speaker 2: are not a small number of people who actively hate
- 28:04Speaker 2: not just not just brown cliders. But it is it
- 28:09Speaker 2: is fascinating that of the fifty three thousand or so
- 28:11Speaker 2: species of spiders on this planet, they're they are only
- 28:15Speaker 2: one of a handful with name recognition. We could probably
- 28:18Speaker 2: name a few other ones wolf spiders.
- 28:20Speaker 1: Wolf spiders. But does do you I feel like I
- 28:22Speaker 1: can say wolf spider. I don't know that I can
- 28:24Speaker 1: picture well, probably.
- 28:26Speaker 2: I think I can. Yeah, to rantle us, you know,
- 28:29Speaker 2: like but like for weavers or weavers, but then there
- 28:32Speaker 2: are different types of weavers, jumping spiders, like eye spiders.
- 28:36Speaker 1: They're my favorite.
- 28:37Speaker 2: They're very, very cute. But but yeah, these are these
- 28:41Speaker 2: are definitely one of the few celebrities of the spider world.
- 28:46Speaker 2: And based on what you told us, Aaron about these
- 28:49Speaker 2: painful necrotic wounds that their bites can cause, that fear
- 28:54Speaker 2: is understandable. Like I'm not going to say it's completely
- 28:57Speaker 2: unreasonable to fear spiders, but it is also out of
- 29:01Speaker 2: proportion to the actual risk that they pose. To most people. Yeah,
- 29:05Speaker 2: Like we said, if you compare a map of the
- 29:08Speaker 2: range of brown recluse spiders with one of diagnosed bites,
- 29:13Speaker 2: a bunch of those bites are well outside the range.
- 29:15Speaker 2: Like there was I think a paper that was describing
- 29:18Speaker 2: brown recluse bites in Colorado saying that they are common
- 29:21Speaker 2: seasonal currents and it's like they don't exist.
- 29:25Speaker 1: They don't exist here.
- 29:27Speaker 2: And if they if they do exist here, they're like transient.
- 29:30Speaker 2: And I'll get into why they're spread is not it's
- 29:35Speaker 2: not very likely, but anyway, they're scapegoats for a lot
- 29:39Speaker 2: of different things. Like you mentioned, there have been diagnosed
- 29:43Speaker 2: brown recluse bites that are actually strap chicken pox, diabetic ulcer,
- 29:48Speaker 2: chemical burns, syphilis, lime disease, Stephen Johnson syndrome, fungal infection,
- 29:52Speaker 2: and even in that two thousand and one anthrax bioterrorism
- 29:55Speaker 2: that's when it was misdiagnosed as a brown recluse bite.
- 30:00Speaker 2: That's wild and it didn't happen like the person who
- 30:03Speaker 2: who had this anthrax cutaneous anthrax did not live in
- 30:07Speaker 2: an area where brown recluse exists. But if you don't.
- 30:11Speaker 1: Have anyone who knows that on your medical team. Then why,
- 30:16Speaker 1: I mean, anthrax isn't exactly common either, so why would
- 30:19Speaker 1: that be the first thing that you think of, So like, yeah.
- 30:22Speaker 2: And this is it's sort of like it's like when
- 30:24Speaker 2: you hear hoof beats, you think horses, not zebras. But
- 30:27Speaker 2: I do feel like a lot of the time zebras
- 30:29Speaker 2: are brown recluse and everyone thinks zebras and don't thinks
- 30:34Speaker 2: don't think zebras.
- 30:34Speaker 1: And horses they're actually zebras.
- 30:37Speaker 2: Yes, yeah, but yeah, there's there's one report that I
- 30:42Speaker 2: thought was really interesting showed that of the six hundred
- 30:44Speaker 2: people they did like a survey who sought help for
- 30:46Speaker 2: a spider bite at hospitals in La and Arizona, eighty
- 30:51Speaker 2: percent of those bites were caused by other arthropods entirely,
- 30:54Speaker 2: So like not spiders, not spiders. But the reputation of
- 30:58Speaker 2: brown recluse spiders is these dead beasties just like laying
- 31:01Speaker 2: in wait to necross your limbs. That's actually a relatively
- 31:05Speaker 2: recent reputation that they got so reckless. Spiders were suspected
- 31:10Speaker 2: of causing necrotic skin lesions as early as the nineteenth
- 31:13Speaker 2: century in the medical literature. At least no doubt people
- 31:16Speaker 2: had made the connection long before and been like, spider
- 31:19Speaker 2: bite is not good, spider bite avoid no one, yeah,
- 31:23Speaker 2: no one, No one wants a spider wright. But the
- 31:26Speaker 2: brown reckless itself was first implicated in that nineteen twenty
- 31:29Speaker 2: nine case report that was in our first hand account,
- 31:31Speaker 2: that twenty four year old woman in Kansas who sought
- 31:34Speaker 2: medical care after being bitten. And in that case report,
- 31:38Speaker 2: like at the very end, he says the well, you know,
- 31:41Speaker 2: no case of poisoning from its bite has been reported
- 31:44Speaker 2: from this region. So that's that's not that long. It's
- 31:47Speaker 2: less than one hundred years ago. And occasional reports trickled
- 31:52Speaker 2: in in the years that followed, and nineteen fifty seven
- 31:55Speaker 2: is kind of when things really shifted. So a case
- 31:59Speaker 2: there was a case that confirmed that a bite from
- 32:01Speaker 2: locks of Cell's reclusa could cause necrotic scan lesions, so
- 32:04Speaker 2: that kicked off a slew of others. And you can
- 32:08Speaker 2: actually see the rise in how often the phrase brown
- 32:11Speaker 2: recluse was used starting in about nineteen sixty. So if
- 32:14Speaker 2: you're reused Google's and gram tool, it's like a tool
- 32:20Speaker 2: that shows you how often a certain word or phrase
- 32:23Speaker 2: or whatever is used over time. So you plot it
- 32:25Speaker 2: and it's like a little bump and then it's like
- 32:27Speaker 2: nineteen sixty, it starts to rise and it's like sotill.
- 32:30Speaker 2: Not very commonly used, but it is interesting. Suddenly the
- 32:34Speaker 2: world had begun to take an interest in this shy spider.
- 32:38Speaker 2: So nineteen sixty and beyond led to this uptick in
- 32:42Speaker 2: fear of this spider. But what else did we learn
- 32:46Speaker 2: in this time? I've got a few spider fun facts few,
- 32:48Speaker 2: I think I have a couple of remaining six eyes.
- 32:51Speaker 2: Got got that terrible vision their nests or not? They
- 32:54Speaker 2: had terrible vision, not very great. Their nests are not
- 32:58Speaker 2: super impressive. They can't balloon so the way other spiders
- 33:02Speaker 2: use their silk to like catch a breeze and they'll
- 33:05Speaker 2: traverse some distances. So if you think of spider's web,
- 33:08Speaker 2: I think Darwin even called them little aeronautsky something like that.
- 33:12Speaker 2: But this this actually keeps their potential for dispersal pretty low.
- 33:16Speaker 2: So when specimens are found outside of their typical range,
- 33:19Speaker 2: it usually means that they were transported by human activity.
- 33:23Speaker 2: So like here's a load of lumber, here's a shipping container,
- 33:25Speaker 2: here's whatever, and so is it likely for them to
- 33:29Speaker 2: get established in that new area? Also probably not based
- 33:32Speaker 2: on just environmental conditions. And so actually I found a
- 33:36Speaker 2: paper looking at what people think the distribution might shift
- 33:40Speaker 2: to as climate change happens, and that out it's north.
- 33:43Speaker 2: It doesn't. It's not range expansion, it's range just shift. Yeah,
- 33:49Speaker 2: let's see what else. They're super shy. Naturally, it's in
- 33:52Speaker 2: the name. But even among other brown recluses, there's not
- 33:56Speaker 2: a whole lot of aggression. Like, they're not social spiders
- 33:59Speaker 2: by any means. There are some spiders that are more social,
- 34:01Speaker 2: but they're not going to cannibalize each other if there's
- 34:04Speaker 2: if there's enough food to eat and enough crevices to
- 34:07Speaker 2: hide in, which is kind of interesting, they can grow
- 34:11Speaker 2: quite abundant within dwellings. So there's a there was a
- 34:15Speaker 2: house in Kansas that was two hundred and seventy meters
- 34:19Speaker 2: squared or about twenty nine hundred square feet, where two
- 34:24Speaker 2: and fifty five spiders were recorded over six months. So
- 34:29Speaker 2: one researcher caught more than eighty spiders in under an
- 34:32Speaker 2: hour by hand. Yeah. Yeah, so they do quite well
- 34:39Speaker 2: in human habitats, and sometimes you will find that in
- 34:42Speaker 2: the edges of their ranges, like of their geographic range.
- 34:45Speaker 2: They're only found within dwellings like human dwellings. Outside maybe
- 34:50Speaker 2: it gets too cold or not great for them, Yeah,
- 34:54Speaker 2: and so they're harder to detect in nature. They also
- 34:57Speaker 2: can live for a surprisingly long time, even though they
- 35:00Speaker 2: are quite fragile, and many throughout their lives will become
- 35:03Speaker 2: injured while capturing prey, so they will lose limbs and
- 35:06Speaker 2: they don't grow back in subsequent molts.
- 35:10Speaker 1: Oh yeah, babies.
- 35:12Speaker 2: There was an experiment that showed that in under house
- 35:16Speaker 2: like environments or conditions with like temperature control and stuff,
- 35:21Speaker 2: male spiders lived on average six hundred and forty six
- 35:24Speaker 2: days and females lived on average seven hundred and ninety four.
- 35:28Speaker 2: So that's like two three years. But twenty five percent
- 35:33Speaker 2: of females lived for more than one thousand days and
- 35:36Speaker 2: the record was one thousand, seven hundred and fifty five.
- 35:41Speaker 2: It's a long time. They are long lived. They are
- 35:44Speaker 2: long lived, very long lived.
- 35:45Speaker 1: But just hanging out in your bookshelf, in.
- 35:47Speaker 2: The book you never reach, it's chilling, yeah, because there.
- 35:50Speaker 2: They also do really well under with very low resources.
- 35:55Speaker 2: So that was with food and water. That's seventeen hundred beyond.
- 36:00Speaker 2: But another experiment found that spiders, these spiders can live
- 36:03Speaker 2: for six months in air tight containers without food, water,
- 36:06Speaker 2: or air.
- 36:07Speaker 1: What So they just like shut down metabolism entirely. I think, so,
- 36:13Speaker 1: just like we will rest, you will really good at that, yep, yep.
- 36:18Speaker 2: But when they do dine, they prefer dead prey over
- 36:22Speaker 2: live prey. And that dead prey could be freshly killed
- 36:26Speaker 2: several months old. Maybe it was killed by insecticides or
- 36:29Speaker 2: another brown recluse. They that's what they like.
- 36:32Speaker 1: Okay, sorry, Then why do they have such intense venom?
- 36:37Speaker 2: I don't know that I really tried to find like
- 36:42Speaker 2: evolutionary blobby blah about venom ecological role for brown recluses specifically,
- 36:48Speaker 2: and maybe my search terms were off. I don't know.
- 36:53Speaker 2: Maybe we are just unlucky that like there's like the
- 36:56Speaker 2: compatibility that venom just happens to be really compatible with
- 37:00Speaker 2: us blood. I don't know, like.
- 37:02Speaker 1: Breaking that's just so interesting if they're mostly eating dead
- 37:05Speaker 1: stuff and they're not aggressive even to other spiders. Yeah,
- 37:08Speaker 1: or is it like because I know and I wish
- 37:10Speaker 1: that I had looked into this more, but I know
- 37:12Speaker 1: there's like you know, the the people who want us
- 37:15Speaker 1: all to be less afraid of spiders will say how
- 37:16Speaker 1: much more potent certain spiders venoms are, but they can't
- 37:20Speaker 1: penetrate our skin right like legs and stuff. And I
- 37:24Speaker 1: don't I've never looked into the veracity of those claims,
- 37:26Speaker 1: but like, maybe that is the case, and so it's
- 37:28Speaker 1: just like combo of bad luck. They've got super sharp little.
- 37:32Speaker 2: I wish I knew more. So interesting, but yeah, they're
- 37:35Speaker 2: very much sit and wait, even if so they'll like
- 37:38Speaker 2: kill something and then weight come back to it later
- 37:40Speaker 2: or whatever. But ninety two percent motionless of their lives
- 37:45Speaker 2: not motionless, motionless, imagine it's quite relatable. Yeah, just like
- 37:51Speaker 2: many days, I feel like ninety two percent. On the
- 37:55Speaker 2: reproductive front, they're not very prolific compared to other spiders,
- 37:58Speaker 2: so their eggsacs can like fifty eggs, about half of
- 38:02Speaker 2: which hatch. But there are other spiders that hundreds to
- 38:05Speaker 2: thousands of eggsack or that of eggs and their eggsacs.
- 38:09Speaker 1: Yeah, yep.
- 38:11Speaker 2: So these spiders, as you can see, have rich lives
- 38:14Speaker 2: beyond their venomous potential. But I will acknowledge that, yes,
- 38:18Speaker 2: their venom is one of the more interesting things about them.
- 38:22Speaker 2: So let's talk about it in a little bit more detail. So, Aaron,
- 38:25Speaker 2: you covered all the ins and outs of this specific
- 38:28Speaker 2: venom of the brown recluse, And so what about spider
- 38:31Speaker 2: venoms more broadly? Again, they are incredibly varied. They all
- 38:36Speaker 2: spiders produce them. Well, sorry, the vast, vast majority of
- 38:39Speaker 2: all spiders produce venom. There are there's one family that
- 38:42Speaker 2: has lost that had once had apparently ability, but they've
- 38:47Speaker 2: lost the ability.
- 38:48Speaker 1: To make fun I'm missting, yep.
- 38:51Speaker 2: And across the over fifty thousand spider species that make venom,
- 38:55Speaker 2: they make a bunch of different kinds. How many we
- 38:58Speaker 2: have no idea because spider VSA is relatively understudied compared
- 39:02Speaker 2: to things like snake venom or even scorpion venom, and
- 39:06Speaker 2: most research looking at spider venom has been directed towards
- 39:10Speaker 2: these handful of species that are medically important. So why
- 39:15Speaker 2: do spiders make venom? Why does anything make venom? It
- 39:18Speaker 2: usually falls into one of three reasons. There's defense, there's competition,
- 39:22Speaker 2: and there's predation. So most spiders make venom to incapacitate
- 39:27Speaker 2: and kill their prey. But defense also, of course plays
- 39:29Speaker 2: a role. So, for instance, some research has found that
- 39:33Speaker 2: in some species, males and females make different kinds of
- 39:37Speaker 2: have different types of venom profiles, with females making more
- 39:41Speaker 2: complex but less toxic venoms. In one situation, this might
- 39:46Speaker 2: be due to how males and females of different species live.
- 39:50Speaker 2: So maybe males of a species are more likely to
- 39:52Speaker 2: encounter a wide range of prey, maybe they have more
- 39:56Speaker 2: generalist venom. For example, maybe females of the species move
- 40:01Speaker 2: around more and carry an eggsack, need to eat more,
- 40:04Speaker 2: so they might have a more powerful venom for defense.
- 40:08Speaker 2: Venom composition can also change from individual to individual and
- 40:11Speaker 2: across the spider's lifespan. Venom is costly to make, so
- 40:15Speaker 2: they're typically going to be very economical with Like, there's
- 40:18Speaker 2: been studies that show that the amount of venom injected
- 40:21Speaker 2: by a spider or deployed by a spider correlates sometimes
- 40:25Speaker 2: to prey size. So if this prey is smaller, they're
- 40:30Speaker 2: going to use less. If the prey is bigger, they're
- 40:31Speaker 2: going to use more.
- 40:32Speaker 1: So they're like really making a decision and controlling those.
- 40:36Speaker 2: Well decision is yeah, okay, they modulate how much venom
- 40:40Speaker 2: is used. How interesting, And they typically will only deploy
- 40:44Speaker 2: it as a last resort, So, especially in a defensive situation,
- 40:47Speaker 2: they're like, can I can I just run away without
- 40:51Speaker 2: wasting all of this venom? Or do I have to
- 40:54Speaker 2: use it? And so that's why like brown recluse, it's
- 40:56Speaker 2: like only in the last resort they're trapped. Oh my god.
- 40:59Speaker 1: Yeah, do we have any evidence do they dry bite
- 41:02Speaker 1: the way that sometimes snakes do?
- 41:04Speaker 2: I think that they do. Yeah, I think that's what
- 41:06Speaker 2: I read. So interesting, But yeah, spiders can inject their
- 41:10Speaker 2: venom with a bite. They can imbue it into their
- 41:12Speaker 2: silk so that if a little critter comes, it can
- 41:15Speaker 2: start acting to either immobilize it or kill it. What
- 41:19Speaker 2: And there's even some spiders that can spray it defensively,
- 41:23Speaker 2: similar to like spitting cobras.
- 41:26Speaker 1: Out of their fangs.
- 41:27Speaker 2: Yes, oh wow, exactly. But however, they deliver the venom,
- 41:31Speaker 2: whether it's specialists or general spiders do it well. They
- 41:35Speaker 2: are some of the most successful and abundant predators on
- 41:39Speaker 2: this planet. Each year, this is if you walk away
- 41:43Speaker 2: with one fun fact, this is okay. Each year, spiders
- 41:46Speaker 2: consume between four hundred and eight hundred million tons of
- 41:50Speaker 2: insects around the globe. Whoa. By comparison, humans consume around
- 41:56Speaker 2: four hundred tons of meat and fish every year. Seriously,
- 42:01Speaker 2: that's what I read.
- 42:05Speaker 1: I am. I am astounded bios numbers.
- 42:07Speaker 2: I know, that's a lot of biomass. That's a lot
- 42:10Speaker 2: of a lot of bio and most of that is
- 42:12Speaker 2: other insects, including those characterized as agricultural pests. A healthy
- 42:18Speaker 2: ecosystem means lots of spiders. They play a big role
- 42:22Speaker 2: in food webs, as both predator and prey food webs.
- 42:25Speaker 2: But exactly, I mean, we use web for so many
- 42:29Speaker 2: different things, I really know, but they and in cultivated
- 42:33Speaker 2: areas like farms and orchards, they are of tremendous importance
- 42:37Speaker 2: in keeping down numbers of critters like aphids or any
- 42:42Speaker 2: other any other like pests. None are coming to mind
- 42:45Speaker 2: right now, but they're especially helpful in areas that are
- 42:48Speaker 2: pesticide free because if you're if you're like, if you
- 42:50Speaker 2: can avoid just like spraying and spraying and spraying, right,
- 42:53Speaker 2: spiders are your friends.
- 42:55Speaker 1: Yeah, they are.
- 42:56Speaker 2: They've also been used in other contexts for biological control pests. So,
- 43:00Speaker 2: for instance, some studies have explored the use of spider
- 43:03Speaker 2: species that prey on brown reclus to keep numbers down
- 43:07Speaker 2: within dwellings. So they're like brown recluse do have natural predators.
- 43:12Speaker 2: If you don't want a house infestation, that's understandable.
- 43:15Speaker 1: They do.
- 43:16Speaker 2: They do pose you a medical risk, and so you could.
- 43:21Speaker 2: So there's been some studies saying, what if we introduce
- 43:24Speaker 2: or have present the other spiders that occur in this
- 43:28Speaker 2: area that prey on brown recluse, it's a great idea.
- 43:32Speaker 2: Another study found that they when they introduce spiders. It's
- 43:36Speaker 2: an old study, but they introduced spiders and houses in
- 43:39Speaker 2: South Africa that preyed on flies. And this is not
- 43:41Speaker 2: brown reckless related, but they found that cases of GI
- 43:46Speaker 2: infections declined with the declining fly population, interesting because as.
- 43:51Speaker 1: They would move around to be gross around.
- 43:55Speaker 2: Yeah, but spiders are on the decline, like in populations
- 44:01Speaker 2: of iraqnids also seemed to be decreasing over the past
- 44:04Speaker 2: decades across the entire globe, and what that will mean
- 44:07Speaker 2: for ecosystems is unclear. Can't be good. One of the
- 44:11Speaker 2: major hurdles though, in conservation of spiders, just like in
- 44:15Speaker 2: conservation of parasites, is the widespread dislike and fear that
- 44:19Speaker 2: surrounds this group of animals. So there's one study that
- 44:23Speaker 2: found that between twenty and thirty percent of people in
- 44:26Speaker 2: the UK felt anxious or fearful around spiders, and an
- 44:31Speaker 2: estimated three to six percent of the global population has
- 44:34Speaker 2: a rachnophobia.
- 44:36Speaker 1: That's actually lower than I expect. Three to six percent.
- 44:39Speaker 2: Well, I think it's to have it be characterized, like
- 44:42Speaker 2: I think, as an actual illness, as an actual illness. Yeah,
- 44:45Speaker 2: it has to reach a certain threshold. There are questionnaires
- 44:47Speaker 2: that try to assess this and like yep, physiological responses.
- 44:51Speaker 2: But I do think that like that twenty thirty percent
- 44:54Speaker 2: of people was specifically in the UK, I think that
- 44:56Speaker 2: that's probably fairly standard, if not like under low, Yeah,
- 45:01Speaker 2: in some areas, higher in others. Yeah, fear of snakes
- 45:05Speaker 2: is up there too, as well as like one of
- 45:07Speaker 2: the other common phobias. But I would guess that more
- 45:10Speaker 2: people know the word a rachnophobia than they do the
- 45:14Speaker 2: phobia for snakes. Do you know the one for snakes?
- 45:17Speaker 1: Nope?
- 45:17Speaker 2: Oh see, I didn't love phobia. No, that's too general,
- 45:21Speaker 2: it's oh video folly, phobia, fideophobia.
- 45:24Speaker 1: Yeah, I didn't know that.
- 45:25Speaker 2: Yeah, me either fear of spider, Like, why do we
- 45:29Speaker 2: fear spiders? Right? And it's been suggested that it is
- 45:32Speaker 2: evolutionarily ingrained within us because the spider bites can be harmful, right,
- 45:40Speaker 2: but the number of spiders that actually pose threat to
- 45:42Speaker 2: humans is pretty low. This is kind of a false equivalency.
- 45:46Speaker 2: But you are twenty five hundred times more likely to
- 45:48Speaker 2: be killed by a human than a spider as an example.
- 45:54Speaker 2: This fear is also heavily tinged with disgust, yeah, which
- 45:59Speaker 2: is is kind of interesting in the context of other
- 46:02Speaker 2: animals that we fear right, Like, I don't think snakes
- 46:05Speaker 2: is highly associated with disgust, right, it's just fear fear, yeah,
- 46:09Speaker 2: And some researchers have suggested that this presence of disgust
- 46:13Speaker 2: points toward it being a learned fear, like carried down
- 46:17Speaker 2: in cultures over the years, and historically in many regions
- 46:22Speaker 2: of the world, spiders were thought to carry disease and
- 46:25Speaker 2: transmit disease. Huh. And so maybe fear and disgusting towards
- 46:31Speaker 2: spiders lingers because we thought that they caused disease disease. Interesting,
- 46:37Speaker 2: It could be both, It could be partially evolutionary evolutionarily
- 46:40Speaker 2: and grained, it could be learned.
- 46:44Speaker 1: I always just thought it was the way that they move.
- 46:47Speaker 1: I was scared, you know, I was very scared of
- 46:50Speaker 1: spiders for most of my entire life and had to
- 46:54Speaker 1: unlearn that fear in Panama, in actually even before Panama,
- 46:59Speaker 1: like in part just doing entomology, having to be able
- 47:01Speaker 1: to hold a tarantula to show to little kids. Yeah,
- 47:06Speaker 1: and then yeah, and then it was just like I
- 47:07Speaker 1: didn't I was embarrassed to be an entomologist in training
- 47:12Speaker 1: and be afraid of spiders. And then having kids, I
- 47:16Speaker 1: was like, I don't want them to be afraid, and
- 47:18Speaker 1: so yeah, so now I like really have to be like,
- 47:21Speaker 1: I'm not afraid at all.
- 47:22Speaker 2: But there is just something linger that.
- 47:24Speaker 1: Lingers where when I like, I will always pick them
- 47:27Speaker 1: up and take them outside. We'll look at them. Oh,
- 47:28Speaker 1: these are so fun and cool, look at their little
- 47:30Speaker 1: body parts. But there's just something inside you're freaking out. Yeah,
- 47:35Speaker 1: hide it very, hide it concealed. Don't feel Yes, I
- 47:41Speaker 1: don't feel.
- 47:42Speaker 2: I liked. I've never had an issue with spiders, cockroaches
- 47:45Speaker 2: and how centipedes have really been my interesting my absolute
- 47:50Speaker 2: terror creep out. Yeah, just vomit, like feeling like nauseous
- 47:55Speaker 2: and cold sweats all over. How interesting apecially, Yeah, but
- 47:59Speaker 2: I mean growing up in we would have the palmetto
- 48:01Speaker 2: bugs and they I was one that like crawled into
- 48:05Speaker 2: my shirt and so like I just I have I
- 48:08Speaker 2: don't like that. Still to this day, Panama was rough
- 48:11Speaker 2: on the cockroach front. I would find them on my toothbrush,
- 48:13Speaker 2: on my pillow, everywhere in my life. On my one
- 48:17Speaker 2: crawled up my naked leg anyway. So, but we all
- 48:21Speaker 2: have spider stories, and it turns out, yeah, and spider's
- 48:24Speaker 2: loom large in many cultures around the world. In Navajo
- 48:28Speaker 2: and Pueblo creation stories, spider woman wove into existence the
- 48:32Speaker 2: world and everything in it, and everything she created remains
- 48:36Speaker 2: connected to her through spider silk, ensuring continued access to
- 48:41Speaker 2: her wisdom and her protection.
- 48:43Speaker 1: That's really nice.
- 48:45Speaker 2: There's the Greek myth of a Rackney, a talented weaver
- 48:48Speaker 2: who was turned into a spider by the envious goddess Minerva.
- 48:53Speaker 2: Mm hmmm mm hmm. She was like, you want to weave,
- 48:56Speaker 2: here you go. You think you're better than me. Ever,
- 49:01Speaker 2: but do spiders show us this? So many different things,
- 49:04Speaker 2: like there's no one word or personality trait that we
- 49:09Speaker 2: ascribe to spiders continuously, right, Like sloths are lazy, foxes
- 49:15Speaker 2: are sly. Spiders are everything. They're there. This is interaction,
- 49:21Speaker 2: this intersection between horror and beauty. They're solitary, they're treacherous,
- 49:27Speaker 2: so many different things. She lob in Lord of the Rings,
- 49:32Speaker 2: it in Stephen King's It is a spider. Oh. They're
- 49:36Speaker 2: also women like yeah, often they are feminine. They are
- 49:41Speaker 2: evoked in stories of fatales. These treacherous and deceitful women
- 49:45Speaker 2: who lay their spiders are also recognized for their creative
- 49:50Speaker 2: talent and their hard working nature. They've given us phrases
- 49:53Speaker 2: like web and network, spinning a tail, and spiders teach
- 49:58Speaker 2: us resilience, like in the nursery rhyme of the Itsy
- 50:01Speaker 2: bitsy spider then crawled up the spout again, and then
- 50:05Speaker 2: every single time, every single time. You just got to
- 50:08Speaker 2: keep doing it. Ebie White, the author of Charlotte's Web,
- 50:12Speaker 2: wrote quote, once you begin watching spiders, you haven't time
- 50:16Speaker 2: for much else. The world is really loaded with them,
- 50:19Speaker 2: Isn't that cute? The story of how he got the
- 50:23Speaker 2: idea for spider for Spider's Web for Charlotte's Web is
- 50:27Speaker 2: he had a like, found a spider in a barn,
- 50:31Speaker 2: brought her in a shoe box to his apartment in
- 50:34Speaker 2: New York. She hatched a ton of spiders and he
- 50:37Speaker 2: just let them like chill, and he was just like
- 50:39Speaker 2: wanted to see them, and he was enthralled and entranced
- 50:42Speaker 2: little spiders. Yeah, and even I think Darwin at one
- 50:46Speaker 2: point on the voyage of the Beagle, became infatuated with spiders.
- 50:50Speaker 2: He said something like, I am red hot with spiders.
- 50:55Speaker 2: He was like just loved watching them and loved watching
- 50:58Speaker 2: them balloon across the the ship. But it is kind
- 51:02Speaker 2: of cool. It's true the world is loaded with spiders.
- 51:06Speaker 2: And I used to do this a lot, especially in Panama.
- 51:09Speaker 2: But I highly recommend next time you're somewhere in nature
- 51:13Speaker 2: at night, could even just be a backyard, take out
- 51:16Speaker 2: a flashlight, headlamp, shine it on the ground. Those glittering
- 51:20Speaker 2: sparkles that you see scattered throughout the grass, throughout the trees,
- 51:24Speaker 2: throughout the bushes, many of those are spider eyes. Yea.
- 51:28Speaker 2: And it kind of is like, maybe that's scary at first,
- 51:32Speaker 2: and maybe it's comforting because how often do you actually
- 51:35Speaker 2: see them. How often do you interact with them? These
- 51:38Speaker 2: things are doing so much work for us. We don't
- 51:40Speaker 2: have to roll out the welcome mats for the brown
- 51:43Speaker 2: reck close to black widows of the world.
- 51:45Speaker 1: Take them out of your house if you don't want
- 51:47Speaker 1: them inside.
- 51:48Speaker 2: Yes, doing this episode, I think I've never had an
- 51:51Speaker 2: issue with spiders, but it did make me kind of
- 51:53Speaker 2: take a step back and go, oh, there is a
- 51:55Speaker 2: lot of work that these spiders do for us, and
- 51:58Speaker 2: they are cute and they are one and so that's
- 52:02Speaker 2: all I've got about brown reckless bites do we have
- 52:06Speaker 2: and spiders in general? I don't know what I'm gonna
- 52:08Speaker 2: do for other Spider Venom episodes.
- 52:09Speaker 1: Hey, we'll have more, don't you worry.
- 52:11Speaker 2: We'll figure it out. But do you have any for
- 52:13Speaker 2: me about the.
- 52:16Speaker 1: No Eric? I think what's interesting is that, unlike almost
- 52:44Speaker 1: every other disease we've ever covered, we probably overestimate rather
- 52:52Speaker 1: than underestimate how often we're bit by spiders in General's so.
- 52:55Speaker 2: Funny, right first, is that the first time I can't.
- 52:58Speaker 1: Remember another time that we maybe someone who knows our
- 53:02Speaker 1: podcast better than we do.
- 53:04Speaker 2: Can tell us.
- 53:06Speaker 1: But especially when it comes to spiders like brown recluses,
- 53:09Speaker 1: like most of the time, if you think it is that,
- 53:12Speaker 1: it probably isn't, which is so interesting. There was a
- 53:16Speaker 1: paper from two thousand and six that went through all
- 53:20Speaker 1: of the case reports that they could find of supposed
- 53:23Speaker 1: brown recluse bites in the US, and of nine hundred
- 53:26Speaker 1: and eight case reports, only eight percent of those were
- 53:30Speaker 1: actually confirmed with a spider and confirmation that that spider
- 53:34Speaker 1: was a brown recluse. So it's really hard to say
- 53:38Speaker 1: how often people are actually being bitten and how often
- 53:41Speaker 1: those bites are bad enough to really need medical care well.
- 53:45Speaker 2: And it's also interesting it's probably both underdiagnosed and overdiagnosed
- 53:48Speaker 2: because how many people get bitten and never realize it.
- 53:51Speaker 1: Never even realize it exactly. Although there was that paper
- 53:55Speaker 1: that you said where they found two thousand spiders over
- 53:57Speaker 1: the course of six months in a house, no.
- 53:59Speaker 2: One was No one was ever bigg Yes, I forgot
- 54:02Speaker 2: to mention that that is a pretty cool.
- 54:04Speaker 1: Two thousand spiders all around your house. Although that was
- 54:07Speaker 1: a big house, you said, twenty nine, twenty undreds big.
- 54:10Speaker 2: It's a big house, big house. It is reassuring, though,
- 54:13Speaker 2: it is very.
- 54:13Speaker 1: Reassuring, right, they're just living among thousands of brown recluses
- 54:17Speaker 1: and never having any issues with it. That being said,
- 54:21Speaker 1: I read that in Brazil, where there's a different species
- 54:24Speaker 1: of los Oficell's, that's most important. There there's about three
- 54:27Speaker 1: thousand annual reports of los Ofcell's bites. Are those all
- 54:32Speaker 1: for sure confirmed? I don't know. That's the data that
- 54:36Speaker 1: I have, And like you said, it is not unlikely
- 54:40Speaker 1: that the distribution of these spiders could change due to
- 54:44Speaker 1: future climate scenarios, not necessarily expand, but who knows. It
- 54:50Speaker 1: just makes it more important that people who work in
- 54:53Speaker 1: the medical profession know where these spiders live, if they
- 54:58Speaker 1: live near you, or have somebody on staff who's able
- 55:02Speaker 1: to help identify spider race, which I think we don't
- 55:04Speaker 1: have enough of. So here's shout out to your local
- 55:07Speaker 1: rachnologist or entomologist.
- 55:09Speaker 2: Does poison control do spider bites?
- 55:13Speaker 1: I imagine that they, but like they're not. You're not
- 55:16Speaker 1: going to be able to like send them your specimens necessarily, Yeah,
- 55:21Speaker 1: as far as I know, so take a picture, but
- 55:24Speaker 1: I don't. I don't know. It's it's a great question,
- 55:29Speaker 1: but that's that's all I have. Aaron for brown recluses.
- 55:32Speaker 2: Brown reckluses. Hopefully we did a little bit of yeah,
- 55:36Speaker 2: pr uplift of the spars.
- 55:39Speaker 1: Don't seek them out, just leave them be.
- 55:43Speaker 2: And that's that's yes, it should we tell the people
- 55:49Speaker 2: where to learn more about me? Definitely, Okay. I have
- 55:52Speaker 2: a bunch of different kind of an assorted collection of
- 55:54Speaker 2: papers by Sandage at All from twenty two thousand and five,
- 55:58Speaker 2: Brown Recluse Spiders over View of Biology, life history and
- 56:01Speaker 2: pest Management was an interesting one. Just an overview of
- 56:05Speaker 2: them by Lytica from twenty twenty two, The Biology and
- 56:09Speaker 2: Evolution of Spider Venoms if you want to know more
- 56:11Speaker 2: about venoms broadly, and then by Davy from nineteen ninety four,
- 56:17Speaker 2: The Disgusting Spider, The Role of disease and illness and
- 56:21Speaker 2: the Perpetuation of Fear of Spiders.
- 56:23Speaker 1: Oh, I love that. I also loved that Biology and
- 56:26Speaker 1: Evolution of Spider Venoms paper. That was my first one
- 56:28Speaker 1: on my list. There's also a chapter in the Handbook
- 56:31Speaker 1: of Clinical Toxicology of Animal Venoms and Poisons from twenty
- 56:35Speaker 1: seventeen that was on the biology and distribution of spiders
- 56:37Speaker 1: and medical importance. There's also a paper that was really interesting,
- 56:41Speaker 1: super recent twenty twenty six in the Journal of Medical Entomology.
- 56:44Speaker 1: That was Recluse spiders Contesting myths on distribution, bye behavior
- 56:48Speaker 1: and medical risk in Florida.
- 56:49Speaker 2: I saw that one. Yea so interesting.
- 56:51Speaker 1: They only have invasive Mediterranean recluse species in Florida and
- 56:55Speaker 1: even those are very low abundance. And they did super
- 56:58Speaker 1: interesting like trying to force these things to bite and.
- 57:01Speaker 2: They just didn't, right, they just wouldn't. They're like, I
- 57:04Speaker 2: don't why this meeting costs me tonight?
- 57:08Speaker 1: Want to keep it?
- 57:09Speaker 2: Yeah?
- 57:09Speaker 1: Anyways, that was great. There was a New England Journal
- 57:11Speaker 1: Medicine paper from two thousand and five, Bites of brown
- 57:13Speaker 1: recluse spiders and Suspected necrotic Arachnittism.
- 57:16Speaker 2: Listen.
- 57:17Speaker 1: There's so many more. Check them out on our website
- 57:20Speaker 1: This podcast will Kill You dot com under the episodes
- 57:22Speaker 1: Tap Yes.
- 57:23Speaker 2: Thank you to Bloodmobile for providing the music for this
- 57:25Speaker 2: episode and all of our episodes.
- 57:27Speaker 1: Thank you so much. Thank you to Leanna and Tom
- 57:31Speaker 1: and Mark and Pete and everyone at Exactly Right for
- 57:34Speaker 1: everything that you do to make this podcast and our
- 57:37Speaker 1: YouTube Hello Possible.
- 57:39Speaker 2: Yes, thank you, thank you, and thank you to listeners
- 57:42Speaker 2: for listening. Watchers for watching whatever, people who do stuff
- 57:46Speaker 2: with this podcast. I need to find a better way
- 57:48Speaker 2: to say this. Thank you. We do this for you
- 57:51Speaker 2: and we hope you like it and it means everything
- 57:54Speaker 2: it does.
- 57:55Speaker 1: We will do more spiders by the way, so tell
- 57:57Speaker 1: us the spiders that you want to hear next. And
- 58:01Speaker 1: a special shout out to our patrons, thank you so
- 58:03Speaker 1: much for your support over on Patreon. It really does
- 58:05Speaker 1: mean more than we have good words to tell you truth.
- 58:09Speaker 2: Until next time, wash your hands you filed the Animals