The Leech’s bonus material returns! In the first bonus episode of Season Two, the guys talk with leech researcher Anna J. Phillips of the Smithsonian Natural History Museum. Dr. Phillips is a Research Zoologist and the Curator of Clitellata and Parasitic Worms.
After hearing about Dr. Phillips’s journey into leech research (1:31), the guys learn more about her leech experiences in the field (8:52), life lessons gleaned from leeches (16:06), and her favorite leeches (22:50). From there, they turn toward the movies, learning about Dr. Phillips’s leechiest films (27:49) and sharing a bit about the pod’s origin story (37:06). They close with some “spoilers” from Dr. Phillips’s upcoming research (42:50) and some shout-outs to sea trench leeches with “tentacles” on their faces (45:44).
We’re always looking to expand our pond -- please reach out!
Series URL: www.theleechpodcast.com
Public email contact: theleechpodcast@gmail.com
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Anna’s Leechiest Films:
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Credits:
Evan 00:29
Well, hello, everyone. Welcome back to the Leech Podcast. This is your host, Evan Cate, and I'm joined by two leechy gentlemen, Aaron Jones and Banks Clark. What's up, guys? [Hey. Hey.] As always, the Leech Podcast is a show about movies that suck the life out of you. But they also stick with you. And they may even be good for you – like a leech. Today, on our very special bonus episode of the Leech Podcast, we are honored to have with us Dr. Anna J. Phillips of the Smithsonian Natural History Museum. She is also the Curator of Parasitic Worms. Dr. Phillips, welcome to the show.
Anna 01:11
Thank you for having me. And please call me Anna.
Evan 01:15
Excellent. All right. Well, Anna, welcome. We can't wait to hear more about your background and your research on these wonderful creatures. Just to get us started, would you tell us just a little bit about your origin story with leeches? How did you come to research such amazing creatures?
Anna 01:31
A lot of people ask me that question. So, I was not like the five year old child who was like, Oh, I'm gonna study leeches someday. That was not my dream. My parents did not – like, I was not that kind of kid. But when I was an undergraduate, I was doing an undergraduate degree in biology. And I saw there were these internships sponsored by the National Science Foundation called Research Experiences for Undergraduates. There was one at the American Museum of Natural History in New York, and you could apply to different projects. And there was one on bees, and there was one on bats, scorpions, catfish. And there was one on leeches. I thought, “No one's gonna apply for that one.” It turned out six people did apply. And I was chosen as the intern. And I – [Congratulations.] Thank you, and then it kind of all started from there. So, all my professors were joking with me because they were like, “Haha, they're gonna use you as bait.” And I was like, “Haha, they wouldn't do that, would they?”
Aaron 02:33
They totally would. [They did.]
Evan 02:35
Yeah.
Anna 02:37
Yes, they did. But the funny thing was, I didn't really, and everything that I thought science should be ended up happening in that summer. So I got to dissect specimens. Like, I worked in the molecular lab, I went to a scientific conference, we did fieldwork. It was a jam-packed summer, and it was everything that I was just so excited about. And then it ended up resulting in a publication. And that project established the relationship, the evolutionary relationships of the North American medicinal leeches. And my advisor got a grant and said, “Come back, and let's work on the evolutionary relationships of the world's medicinal leeches.” So that project expanded out into my PhD work. And I kind of always thought of leeches as like aquatic invertebrates. So I was thinking of them, you know, because leeches are blood feeders. [Yes.] And so I was thinking of them more from this ecological standpoint, as you know, a worm in freshwater or other habitats, I was focusing on freshwater. And about halfway through my grad career, we couldn't go to the conference we wanted to go to and my advisor suggested, “Hey, let's go to the parasitology meeting.” And I was like, oh, yeah, I guess leeches do have a place in parasitology. So we went there. And it just opened my world there to hear about all of these amazing parasites, parasitic worms that are multicellular animals living inside of other animals. Yeah, it just blew my mind. So when I graduated from my PhD, I sought out a postdoc working on tapeworms, specifically tapeworms in birds. Yeah, and I just went headlong into parasitology. And right after that, this job opened up here at the National Museum of Natural History, and that was 10 years ago.
Aaron 04:31
So you've been at the museum for 10 years. What does your work look like there? What do you do?
Anna 04:36
So technically my job title is a Research Zoologist. And that means I also have curatorial responsibility for many of our worm collections. So I have curatorial responsibility for the leeches, as well as the clitellate annelids, including the earthworms. And then I am also the Curator of the U.S. National Parasite Collection, which includes things like your tapeworms and the nematodes, roundworms, spiny-headed worms like acanthocephalans. The nematomorphs, the ones that form Gordian knots, like, a whole bunch of other stuff that most people have never heard of is in this collection.
Aaron 05:14
Where is this collection? Like, I've never been there.
Anna 05:21
Well, you may have been close. So I'm coming to you from my office in the Natural History Museum on the National Mall, in Washington, D.C. And so some of our collections are housed here in this building, but most of the worm collections are kept at the Museum Support Center, and that’s a facility in Maryland.
Evan 05:40
So just for listeners, we will provide links to many of the worms and the creatures that Dr. Phillips just described, so that you can get – there's some pictures that she sent us that are… you just got to see him to believe them.
Aaron 05:53
Oh, so can anyone just go to the center and ask to see the collection? Is it that simple?
Anna 05:59
So unfortunately, not. [Noooo!] So… I know. But, that said, the Museum Support Center, it houses more than just Natural History collections. So there's other museums that have their collections out there. So it's pretty heavily guarded. [Oh, geez.] Yeah. I mean, like you can’t just keep all the dinosaur bones and you know, the whale skeletons and everything on the National Mall. [I guess you're right.] Yeah. So the Smithsonian has the largest museum collection in the world. And most of that doesn't make it on exhibit. [Wow.] But we keep it for research purposes. And so research visitors can request access that can be approved for specific projects.
Aaron 06:40
Fascinating.
Banks 06:41
So how many like varieties of leeches – how many specimens of leeches do you think are at the Smithsonian?
Anna 06:49
So our collections here are the national collections, so this is the National Leech Collection. We have over 17,000. And I should say that's jars. That's not 17,000 leeches. Because each jar may have one leech or it may have 100 leeches. [Wow.] So and we don't want to sit there and count all of them, because for our purposes, we just need to know how many jars we have. 17,000 jars.
Aaron 07:17
Wow. And this is a global leeches from all kinds of environments, yeah?
Anna 07:22
Yeah. So leeches occur in – most people are familiar with the freshwater leeches. You may have heard of the terrestrial leeches. And then there's also marine leeches. And our collection includes specimens from over 100 countries. So we have pretty broad geographic coverage in this collection. It's a pretty big leech collection.
Aaron 07:39
I gotta say I have a very niche specific question. I was reading your article from 2020, “Leeches in the Extreme.” And you mentioned this giant red leech. Is it from Borneo or something?
Anna 07:52
Yeah, the Kinabalu Red Leech?
Aaron 07:55
Gosh.
Anna 07:56
Yeah, it is from Borneo.
Aaron 07:59
Can they grow like 20 inches long or something? [Yeah.] Oh my.
Anna Phillips 08:02
Yeah, yeah. There's a lot of really cool YouTube videos. If you look them up on YouTube, they are mostly burrowing. So a lot of times they're encountered by hikers after rainstorms. So he's hiking along and they find this like, really long, bright red worm in the trail. And most -- sorry, my lights just went out -- we're eco-friendly here. We have automatic lights that turned off. Yeah, so these tourists or anyone hiking in the forest, you know, after a rainstorm, they're walking along and there's this really long bright red warm in the path and a lot of times it's out foraging and so it's called an earthworm. And so it's slurping down this earthworm. [Wow.] Which makes for pretty good YouTube videos.
Aaron 08:46
Oh, wow. Definitely looking this up immediately after the conversation. What? Worms eating worms.
Evan 08:52
Wow. Yeah. So speaking of being out in the field, I guess, do you have some stories from your field work, from your research, encounters with leeches that you've had?
Anna Phillips 09:02
Um, yeah, there's been a lot. Um, so I've been to six of the seven continents, [Wow] searching for leeches at this point [Amazing] -- some more than others. Some of my favorite trips ended up going to places where people don't really get researchers coming in that often. And so one of the common conversations I end up having is, they're like, why are you doing this? Why are you here? Sometimes this happens with translators, right? So I can't speak with the person directly. But when we're going through a translator, and the translator's saying like, "They don't believe you. They don't believe that you're here for science." And I'm going, "No, no, tell them that like, their leeches are very special. Like, we don't have these kinds of leeches where I'm from." And so, when we were in Rwanda, we were working with this translator speaking Kinyarwandan, and he said, "No, they really don't believe you. Like, you didn't come all the way from the United States just to collect our leeches. Like, they're everywhere." And I'm like, "Yeah, no, that's great." And I tried to explain they were like, "No." [No] "No, you just came here to eat them. We're pretty sure you came all this way to collect them so you can eat them. That's the only reason that the people will come from the United States." I'm like, "No, seriously, do you eat the leeches?" And they're like, "No, but you guys, you probably do things like that in the US." It was a food source. Wait, does anyone eat leeches? Is that a part of any human cultures? Dietary supplementation?
Evan 10:24
Is it a delicacy?
Anna Phillips 10:26
So I've looked into this a little bit, because there are some tales of... You know, biologists do weird things. And sometimes it's a lab initiation, there's an eat-your-organism idea. I don't recommend eating leeches, but the people who have done it, I've heard they taste like mud. I've not done it. I don't see a reason to. But as far as the cultures in the world, there are some reports from Papua New Guinea with some tribes that it was a delicacy for them to eat leeches in certain ceremonies and rituals. And they have some attached belief with what that gets you. I'm not -- I don't remember all the details of this part of it. But [Oh my goodness.] that's the only reference I've seen of people willingly eating leeches.
Aaron 11:13
Ceremonial leech eating.
Anna Phillips 11:15
You can accidentally eat leeches. Or they, you know, sometimes people drink them or they get them from drinking water. But that's usually accidentally.
Aaron 11:23
One would hope, or one would think. Have you ever interfaced with the medical world where people are either experiencing leech-related trauma or whether they're using -- like someone who swallowed a leech, and it's like in their throat latched on -- or where people are using the leeches medicinally? Because you've studied the medicinal leeches...
Anna Phillips 11:43
Right. So I don't have any medical training. I don't have any veterinary training. [Okay] And so my interest is more of, like, reading about their reports. So I haven't been consulted on active cases. But I have combed the medical literature looking up cases of hirudiniasis and trying to find out like, what happens? How is it treated? I also hear a lot from either the public or from the physicians when they come by the museum and say, "Oh, leeches. Yeah, we use those." And I go, "Really, do tell. I want to know more about this." I have not received leech therapy myself, so.
Evan 12:20
Okay. Well, I guess that's related to one of my questions. We've talked to leech researchers in the past who said that they have actually allowed leeches to feed on them, maybe over 100 times. Is that a part of your research as well, or...?
Anna Phillips 12:34
I generally try to avoid it. Um, it is an occupational hazard with this job. Sometimes they do get to you. And I have, I mean, I have intentionally fed leeches in the past. Usually, it's with a TV crew or something where they like, they need a certain kind of footage. And, you know, I'm not gonna, like, make an intern do it. I mean...
Aaron 12:57
One could do that.
Anna Phillips 12:59
Yeah, like, I'll do it myself. Um, but I generally try to avoid that. The leech saliva has a lot of properties in it that can create allergies. And so if you do this for your whole career, you can end up developing an allergic reaction over time to it, and I'd like to avoid that. So when we're in the field, and we try and catch the leeches before they bite, they'll attach without biting. So try and catch them before they actually latch on and bite but it is inevitable when you're gonna, when you're out doing all this, you're gonna get bitten at some point, right? Keep a healthy stock of band aids. Right?
Aaron 13:36
When you were in Rwanda, what kind of leeches were you gathering? And were you just kind of walking into water sources and collecting them on your legs? I mean...
Anna Phillips 13:44
Yeah, so when we do big trips, I'm looking for any leech that I can find. So I usually write the permits to include everything because there's not much chance we're gonna get to go back to such an exotic location like that. So there were certain species that we were targeting in that, for my PhD work, but then we also collected every leech we could find that. Also, because all of these specimens went into the museum collection, and so they're available for other researchers and future projects. And sometimes for projects we don't even anticipate right now. So, then new technology can come up all the time. So yeah, with the work we were doing there, we did, you know, we did get into the water to try and attract the leeches. But there are some leeches that aren't attracted to humans. [Oh, yeah.] So you have to work a little bit harder for those. And that involves going through like the leaf litter or trying to go through the sediments in the bottom, turning over rocks and submerged debris.
Aaron 14:43
Yeah, I was looking for tips and strategies for us and for our listeners. Yeah.
Anna Phillips 14:47
You can also trap leeches. [Oh, say more.] I've seen -- again, YouTube -- there's some pretty cool leech traps that people have fashioned out of like aluminum pie plates. [Excuse me?] So you can take an aluminum pie plate and put a piece of liver in the inside, fold it in half, and then secure it together with string or something, and then toss it out the water. And the blood from the liver will attract leeches in and then leeches also tend to like flat surfaces. So the aluminum pipe plate's perfect. And sometimes they'll just attach just because it's nice and flat and they can stick to it really well.
Aaron 15:26
It's so satisfying to them. Like ooh, this is so flat. That's so nice!
Anna Phillips 15:30
That's just so comfortable for them. It's like a cozy couch. They're like, "Oh, this is right where we want to be. And there's beef liver."
Evan 15:40
What more do you want? What more do you want?
Aaron 15:41
And they probably get so engorged that they can't leave the trap. Is that the...?
Anna Phillips 15:46
No, no, they just stick around. [Oh, they just stay?] Yeah, they can leave if they want. I've definitely put out traps and then come back, and then like, "I know you were here. Where did you go?" Yeah, they just didn't -- I didn't come back soon enough. So it's something you have to kind of get a feel for in the habitat you're working in. Leeches, there's never a guarantee with leeches.
Banks 16:06
Well, so I have a question that is: so you know, Aaron Jones at the start, sort of said, you know, that we live in the land of metaphors on this podcast. And the leech is this metaphor for how we are thinking about these different movies. And one of the questions that I have is if, in your experience, there have been leeches or some aspect of leeches have acted as a particularly potent lesson or metaphor that you found? Like how are leeches interesting? How do they inform aspects of either how you think about something interesting about, like, either living or a movie? Or if something really ridiculous as well, just like, oh, this is just a really interesting fact.
Aaron 16:47
The question is not what can we learn about leeches, but what can we learn from leeches? [Yeah!]
Anna Phillips 16:52
Oh, what do we just have to teach us? [Yeah.] Well, leeches have taught me a lot over the years. So I've been working with them for like a scary amount of time, like 20 years. So I think I probably gained a lot from them. One thing I think with leeches is that it's a relatively small group of worms. Like when you think about all the different species in the world of worms, like, there's like 16,000 species of nematodes or something. And there's probably like, 800 species of leeches. So there's not that many in comparison, but they pack a lot of diversity in there. There's something really nice about that, something really pretty about like, it's not always about volume, or size, or like how many, you're like being the biggest and the best, like, sometimes just the quality. You know, quality over quantity. And then, on top of that, I think one of the frustrating things I have is when other scientists, people were doing a lot of water quality surveys, and they'll find leeches, and they'll just write down “leech.” And there's so much more to the story. And if you just look a little bit deeper, there's like all these different kinds of leeches. And they can tell you all these different things, because they have different habits -- not just habitats, but they have, you know, different modes of life, like some are predatory. Some specialize only in earthworms, some are blood feeders, but only feed on turtles. Some only feed on fish. There's so much diversity there that can tell you so much more. So a lot of times when I'm working with people who aren't necessarily leech specialists, I'm encouraging them to dig a little bit deeper. There's probably more than you would know, just by writing down “leech.” They have a lot more to offer. So I guess like life lessons wise, like, that's kind of what it's brought me, is that it's not always kind of as simple as it seems on the surface.
Aaron 18:45
Wow. That's beautiful.
Evan 18:47
Yeah, that's lovely. It sounds like you're saying that, you're looking at a leech in a habitat, and it actually tells you more about the habitat than you might realize at first.
Anna Phillips 18:54
Definitely about the habitat, and then also the other species that it's interacting with. So like, what are they feeding on? So if you're finding a certain kind of leech, you'd be like, oh, there's turtles here. If you find another kind, you're like, Oh, those are amphibian specialists, there's definitely going to be a load of frogs. So it may not even be animals that you're seeing while you're there. And there's been some really interesting studies on using what they're calling ingested DNA, where they've been taking the blood meal out of leeches and sequencing that. [Yep.] Yeah, you've heard of this?
Aaron 19:23
We read a really interesting article about that from... it was like a Chinese nature preserve was using that to like, to document all the creatures that were there, just by looking at the leech blood meal. Yeah.
Anna Phillips 19:38
Yeah and it's...there have been, especially in -- there were some studies in India where they were finding like these muntjac species that hadn't been seen in decades, but they found DNA of it in the leech blood meal. And so that's a way to search for these really elusive endangered species that may be extinct, and it's a way to kind of like -- without really disturbing them in their habitat. So yeah, there's some really cool applications to it. And it also tells us more about what that leech species is eating. [Yeah.] So they may not be a specialist, they may have a more broad feeding preference.
Evan 20:16
I wonder too, this -- the phrase "canary in the coal mine" is coming to mind. Like, if you see a certain kind of leech in a habitat does that... Like is it a warning sign for something in what's going on in that environment? Or is there any way that like, if you see a leech here, you're like, "Oh, wow, that's surprising. Maybe we should worry about something"?
Anna Phillips 20:34
That can happen. Most leeches, when you're seeing them, especially if they're in the water, they indicate -- usually -- indicate good water quality. So like, they like pristine environments, usually I think places that are less disturbed. There are, of course, some species that are the opposite. And they prefer, you know, tons of organic pollution. Places where there's tons of people tromping through, so they have lots to eat. So it really depends on the species. There are a couple of species of invasive leeches. So leeches that, when they get introduced to a new place, they will happily survive and reproduce. And so we have at least one species of leech that has made it to I think, five or six continents at this point. [Oh wow.] So when we see that one pop up in a new location, that is a warning sign. They're getting transported on aquatic plants. So people aren't meaning to do this. They're just buying like cool plants for their pond, and leeches come with them. And it may even not even be the adult, they may be so small, they don't even know they're there. [Wow.] So that can be a warning sign.
Aaron 21:38
Is this a species -- you mentioned a species in "Leeches in the Extreme" that it can self-impregnate because they're hermaphroditic, and it can lay up to like 100 cocoons within a short period of time. [Yeah.] Is that the one you're talking about?
Anna Phillips 21:52
I think so? I would have to go back and double check. But yeah, all leeches are hermaphrodites. Selfing isn't probably as frequent. It's not the smartest evolutionary strategy, like you want to mix your genes up with somebody else. But it definitely poses a huge problem when it comes to these invasive species.
Aaron 22:12
Where are they coming from? Like the species you're talking about? Where's its origin point?
Anna Phillips 22:16
So the one that I'm talking about is Barbronia weberi, and its origin seems to have been in eastern Asia. [Hmm. Interesting.] You know, it has been reported in Europe and South America, all over...throughout Asia. It's yeah. I mean, thankfully, we don't -- Well, we don't really know about its impact on ecosystems it makes it into. So that's one of the species we will call "data deficient." So I don't want to tell you that it's not a problem, because we don't see an obvious impact yet, but we just don't know.
Aaron 22:50
Do you have a favorite kind of leech, or a couple kinds? I mean, [I was just gonna ask the same question!] many are vying for your affection, I'm sure! But...
Anna Phillips 23:05
I have thought about this a little bit and I was actually just telling someone yesterday. I said, "It's really hard to pick a favorite, because I have to think, like the ones that I always want to read more about? Or the ones that I find the most interesting research questions? Or like the ones I like to collect the most? Like, it's really hard to pick. I mean, I will say the mucous membrane feeding leeches, like those are the closest to my heart. It's my third scientific paper and like, those are... And they're really interesting geographically.
Aaron 23:35
What's that family called?
Anna Phillips 23:36
The Praobdellidea.
Aaron 23:40
Yes, I think when we originally cited your article in an episode of the podcast, that's what we focused on. Because you mentioned them going, sometimes traveling with people on airplanes, because they've ingested them somewhere. The mucous membrane.
Anna Phillips 23:58
Yeah, yeah. We call those "souvenir parasites." You didn't entirely mean to bring them home with you.
Aaron 24:09
Well, and how do you... So if... You can't walk into a pond and just pull that off your leg. Like how do you study the mucous membrane feeders, the praobdellid leeches?
Anna Phillips 24:18
A lot of the praobellids, a lot of them have adaptations with their jaws. So these are jawed leeches. They have adaptations with their jaws to feed on thin mucous membranes. Because like, that's not your skin. Like that's up your nose and your mouth, and then other more sensitive areas of the body. So their jaws are -- they don't have as many teeth and their teeth aren't as robust as a lot of the other leeches that are trying to bite through skin. So that means that a lot of them will actually also feed on amphibians because the amphibian, their entire bodies are a mucous membrane.
Evan 24:56
Oh, right. [Makes sense.]
Anna Phillips 24:58
So they'll feed on like salamanders or frogs. But then, you know, if they have the opportunity to go inside mammalian orifices, like "Hey, yeah!"
Aaron 25:07
Yeah. Equal opportunity feeding, yeah.
Anna Phillips 25:11
And the reason they'll come back with the tourist is because, once they go in the orifice and they feed, they don't necessarily leave. Because they've got this nice, dark, wet place with a ready food source, and they're like, "I'm good." And they can hang out there for months. Just continually feeding over and over again.
Evan 25:27
Oh, so they -- so this is a leech that feeds continuously. They don't feed once a year, and they're good? They keep feeding?
Anna Phillips 25:34
So it's a family of leeches. And they, I mean, it depends on... If you ask a leech, if you present them with, you know, a feeding opportunity, they're not going to be like, "Oh, I'm sorry, it's only been 11 months." Like, they're gonna be like, "Oh, yeah." You know, they're going to take what they can get. So if it's been -- so these leeches don't necessarily feed until they're completely full. So especially when they're in a situation like an orifice, they've got this ready food source, they may not feed until they're completely full. They'll feed like halfway, digest that.
Aaron 26:05
Snacking. Just snacking. Snack attack.
Anna Phillips 26:09
I mean, so a leech that was out in the water, you had to do a stealth attack. Come up, feed on your leg before you realized it or left the water. It's going to have to feed as much as it can in one go, before you leave. And then you know, that way it gets as much as it can in that one opportunity, because it doesn't know when another animal is going to come by. But a leech that's inside doesn't have that pressure.
Aaron 26:32
Can I just jump in with a reference that really surprised me? And I'm wondering if this is a praodbellid leech. You said in your article that there's a leech that specializes in the anal penetration of hippopotami. [Wow.] Like it ventures up that canal. [Wow.] Specializes in it? .
Anna Phillips 26:53
Yeah. Placobdelloides jaegerskioeldi. Yeah. I have not collected that one personally.
Aaron 26:59
Thank God. [I hope not!]
Anna Phillips 27:01
I have colleagues that have. They did not wrestle the hippo. But yeah, I mean, I... You know, you'd have to ask the leech why that's their favorite spot, but... [There's a lot of other stuff up there!] I will say like, evolution is -- evolution can get really specialized sometimes. Now, when they're not associated with a hippo. I don't know where they go. [Fair.] Yeah. And then also with the praobdellids, we know that if the leech is coming through water, they'll attach, you know, again on a lower limb or something. And they'll move north, they'll just keep going up. They're searching. They know what they're going for. [Wow, okay.] Sorry, this may not be lunchtime conversation.
Aaron 27:46
No, no, it's good. It's good. I'm glad I ate before the conversation.
Evan 27:49
Yeah, same, same. Well, should we turn it in a movie direction a little bit? This is a movie podcast overall. Although we do love the leech science that we bring in. Aaron actually does a Leech Anatomy 101 segment in every episode, which was how we first came across your research. [Oh, that's awesome.] So thank you. I guess, you know, one of our questions is, like, Are there movies for you that you think of as leechy? Now you can take that as literally or metaphorically as you'd like. Like, what's your favorite leech in a movie -- that's a way you could go. Or, just movies that, you know, stick with you, take the life out of you, maybe? Those are movies that are near and dear to our hearts. But yeah, are there movies, as you think about leechiness, that stick with you?
Anna Phillips 28:33
So, this can be a deep subject for parasitologists. Because like, how parasitic worms are portrayed in movies is this...Yeah, there's a lot to be said about this. There's a lot of candidate movies, as well. [Sure.] I'm guessing if you guys know... if you've talked about leeches in movies, like there's -- I can probably name like four off the top of my head.
Aaron 28:56
Yeah, rattle them off, what do you got?
Anna Phillips 28:57
I mean, the first is like, The African Queen. I mean, this is a classic, where, you know, they're carrying the canoe through this wetland they can't get through, and Humphrey Bogart is dragging the canoe and he gets out and he's covered with leeches. [Right.] Katharine Hepburn is throwing salt at him, trying to get them off. Amazingly, when they get the leeches off, he's not bleeding.
Evan 29:19
I think I read this in the article that you wrote -- that we'll include on the episode -- that actually it's unadvised to use salt now to detach a leech? [Right.] It's better to use, like, your fingernail, is that right?
Anna Phillips 29:30
Yeah. Honestly trying to use salt or like trying to burn them off, it's a bit over dramatic for what's really happening. So leeches, you know, they have two suckers, they're like suction cups that stick to the window. And so to get them off, you just have to break the suction and then toss them back into -- hopefully back into water. Like, do them a favor, you know? But when they're feeding, they are sucking out the blood. And if you do something like salt them or burn them, it threatens them, and then they're going to try and reduce their body weight to escape. And that means that they are going to vomit, and they're going to vomit all that blood that they just ingested. But more importantly, they're going to then vomit up the bacterial component of their digestive system into that wound. And those bacteria, that microbiome, when it gets into you, it can cause an infection. It doesn't happen every time. I've had lots of people tell me, "I've always salted my leeches for years. I've never had an infection!" I'm like, "Hey, count yourself lucky." But I don't want to chance it. There's a much easier way: you just use your fingernail, just to -- I mean, if you pull, the leech is going to stretch. So it's not the best way. But like, just use your fingernail, break the suction, throw it back. Put a bandaid on, you'll be okay.
Aaron 30:42
I always, I always use salt with a little bit of herbs de provence, you know?
Anna Phillips 30:49
Yeah, black pepper is too far on this.
Banks 30:52
Pink Himalayan salt is the best.
Evan 30:54
Sorry, I diverted us from leechy films.
Aaron 30:55
No, no African Queen, African Queen.
Evan 30:58
I know there's like, Stand By Me, which is a famous one.
Anna Phillips 31:01
Yeah. I mean, Attack of the Giant Leeches. Which, I mean, if we're gonna be doing some film criticism, you know, film reviews, I would say that one doesn't have enough leeches in it. [Oh, what?] Despite its title, it needs more leeches. Yeah. Go back and watch it. Like, they talk about leeches a lot. But you don't see them that much.
Evan 31:24
[Fascinating.] I wonder if that's an old Hollywood movie that should be updated, you know? Now that we have the technology to really portray a lot of leeches.
Anna Phillips 31:31
It's true. And get them a little more anatomically correct, too.
Evan 31:35
Yeah, we could CGI like, a billion leeches on there. Yeah.
Anna Phillips 31:38
Oh, no, no, I want miniature leeches. I want real models.
Aaron 31:42
We just need some really brave actors, you know? [Yeah.] Who are willing to go all the way with the role.
Anna Phillips 31:48
Yeah. Yeah. So those are all classics. There's actually a couple of Grey's Anatomy episodes with leeches in them. [Oh.] I know this is a movie podcast, but we can veer into TV a little bit. [No, no, no. Bring it!] Yeah, yeah. So in the second season of Grey's Anatomy, like one of the, like, one of the first episodes, I want to say. There was, I can't remember what happened to him, but like he had to have skin grafts on his nose. And they use leeches to treat that. And then the shocking part of it, the reason in the TV show is, because the guy afterwards is like, "What's gonna happen to the leeches?" And they said, "Oh, you know, we incinerate them. They've been -- they're a medical device. They've been used." And he was like, "No, no, I want them as pets. They did me a huge favor!" So there's that one, and then later on... Yeah, well, yeah, much later on, there's a woman who has a leech up the nose after traveling.
Aaron 32:42
Nice.
Anna Phillips 32:44
Pulled from the headlines. So. And they have to figure out how to get it out.
Aaron 32:51
So I mean, they're dealing with the real subject matter. I mean, this is...
Anna Phillips 32:54
Yeah, yeah, those are real, those are real cases. I'm sure that was pulled from real things. Um, especially leech in the nose. There was one in the news, a while back, of a lady who had been in Peru, swimming (I think it was Peru). She had gotten a leech up her nose and brought it back. And then was very distressed about getting it out!
Aaron 33:12
Distressed? I don't understand.
Anna Phillips 33:16
Yeah, it was not something she necessarily thought she was bringing home with her. But...
Evan 33:21
You know, it's interesting. One of the films that we've done for the show is Parasite. And as you're talking about parasites living inside the host -- literally inside the body of the host -- that made me actually think about that movie, where this, this family is secretly living inside the actual house of this other family.
Anna Phillips 33:39
I'll admit, I haven't seen it because I'm terribly behind in my queue.
Evan 33:43
Oh, it's well worth your time. [It is!]
Anna Phillips 33:45
Well, yeah, but I also heard that there aren't actually parasites in it. Like it's a metaphorical parasite. And it was like, aww. [It is metaphorical, yes.] That really, it brings it a step down for me. I mean, it's probably still a good movie.
Aaron 33:56
Interesting. So I mean, when you, when you're watching films and TV, are you normally trying to find content that includes your work? "Well, if it doesn't have a parasite in it..."
Anna Phillips 34:07
I'll just say that, if it does have a parasite, I'm probably gonna watch it sooner.
Aaron 34:10
Ehhh, wow. It goes up the queue! .
Anna Phillips 34:13
Yeah. Another one, oh one of my favorite movies -- I actually have this one on DVD -- is this 1970s horror movie called Frogs. And, yeah, it's about... It's a low budget horror film from the 70s. I love it though. This family is having a birthday party on this island in Louisiana. And they have like -- I don't know -- they're a very wealthy family and they've definitely done something terrible to the world because the environment just attacks them and takes them out one by one. So you have to understand the premise of these movies is like, you know, if the snake hits you, you die immediately. I mean, there's no chance of survival. So there's like snakes flying and hitting people. There's like turtles coming up and like I mean frogs -- and of course there's frogs, right? Like frogs are coming out and taking over. And there's this one woman who tries to escape. She runs away. Of course a snake hits her, she falls into this pond. And the leeches come in. Exactly. [Wow.] Yeah, I totally recommend it.
Aaron 35:20
Yeah, I mean, it just went up on my queue. [We'll add that to our list.]
Anna Phillips 35:23
Yeah, because of the whole like parasites in movies, I've gotten into horror movies, where that was never my thing before.
Aaron 35:31
Wow. Specifically, parasite horror. [Yeah.] As opposed to -- you're not watching like Chainsaw Massacre slasher films. [No.] No. [No.] Yeah. Not so much.
Evan 35:44
Do you feel like...Sorry. My question is like, do you feel like parasites and maybe leeches get a kind of bad rap in Hollywood? [Oh, yeah.] You know, there's so much more going on here that I feel like Hollywood needs to portray these amazing creatures in a more robust way. Is that fair to say?
Anna Phillips 35:59
Yeah, I mean, I have two ideas on this one. Yes, we should portray them in a more friendly fashion, because they are, you know, providing more connections in our ecosystems than we realize or moving energy in ways that other animals aren't. You know, they're just as important. And they have these, you know, close associations with hosts that is just fascinating. We can learn so much about them. And once we figure out some of the mechanisms that parasites are using to survive, we can apply that to so many aspects of human life that could really be transformative. But it's also really fun to watch a parasite horror movie. It's kind of fun to be scared by them, too. I mean, it's not unrealistic. Parasites do scary things, you know, especially a worm living inside of you and like, you know, doing harm -- but it doesn't actually kill you. That's, that can be unnerving. And sometimes we like to scare ourselves. I would like to, I mean, I'd like to someday see a more leech-friendly, the good side of leeches in film, but I'm not going to hold my breath.
Evan 37:01
We long for that, too.
Aaron 37:06
It brings me back to -- I think we promised you earlier we would tell you a little bit about our origin story. [Yes.] [Oh, that's right.]
Anna Phillips 37:13
Yeah. Because this like leeches plus movies... You've mixed it in a way I didn't expect.
Aaron 37:18
Yeah, this is like scrambled eggs of stuff. So let's take the eggs back apart. I guess it was based on, you know, conversations years ago about a really specific kind of movie that would cause us to have, you know, almost a recognizable pattern of experiences. And not knowing exactly what to do with that. So for example, one of the key features of a typical leech movie is that you watch it, you turn it off and say, "Oh my God, I never want to watch that again." But, but -- there's a but to that -- which is that, after further reflection, because the movie is hard to forget, right? The very reason that you didn't want to watch it again, is because it left a big imprint, or it was so difficult in some way. But then after further reflection, you realize, you know what, maybe several years from now I could watch this again. And you do and then you realize, oh my God, this movie is brilliant. This movie is teaching me something. It stuck. It sucked a lot of life out of me -- so much that I thought, "Never again." But then it stuck with me so much that I stayed around long enough to get it, to get medicine from it. To get that hirudotherapy, you know? And this is an experience that we've had, like, repeated with different films. Like the first movie that we dealt with in this way was called, There Will Be Blood. Have you ever heard of that one?
Anna Phillips 38:50
I've heard of it, but haven't seen it.
Aaron 38:52
It's about oil drilling.
Anna Phillips 38:54
Yeah, I heard it was really heavy.
Aaron 38:57
[It is.] Which is, it's very, like proboscis-like, though, right? The oil drilling pulling the blood out of the creature, out of the earth. And so you can see how like, metaphorically, it kind of has this leechy quality. But also, our physical, visceral experience of the film: we were trying to describe it in this simile or metaphor of the leech -- it just kind of emerged naturally, organically.
Evan 39:22
Right, so one thing we do on the pod is we talked about the leechiness in various aspects of the film. We then talk about the hirudotherapy from the movie. [Okay.] So any ways that it's helpful, medicinal. And then we give a rating at the end. So we rate every film from one to four leeches. Really, really leechy movies, get four -- all the way down to one.
Anna Phillips 39:48
These... Okay, a rating of four. That's an intense experience.
Evan 39:51
So true. There's only been a couple. [Okay, yeah. What were the two?] Parasite was one. I think There Will Be Blood.
Anna Phillips 40:02
So that's two things I need to do this weekend.
Aaron 40:05
Oh, wow. [Buckle up!] That's gonna be a hard weekend. [Uh-oh!] Well, I think it comes back to the question about like, Well, why do we watch movies? Or why do we, you know, look at art? I mean, is it just to be entertained? Or is it for something deeper? [Right.]
Banks 40:22
I mean, to your point, when you're mentioning leeches that are sometimes like, overlooked, or sometimes researchers, like don't give them the time or perhaps or even a little bit, you know, put off by them or revolted. Like some of these movies are, they're an investment, they're the ones that you normally, you know, like, this isn't just going to be something that you're just going to sit and enjoy. But like you actually watch it and you leave and you're like, there is something -- this intangible, we call it, you know, the hirudotherapy of a movie, right? That's like, Oh, this is actually really good. And it just speaks a little bit more to that. And so it's the kind of movies we try to do.
Aaron 40:55
Have you ever had a movie like that? Where you watched it, and you were like, "Oh, no, I can't watch that again!"
Anna Phillips 41:09
I'm certain. I don't know. You describe, like, so many elements that make it so intense. Like any one of those things I could, I could say, but like packing it all into one is, is a challenge. [That's true.]
Aaron 41:20
Yeah, it's a rare quality.
Anna Phillips 41:23
Yeah. I mean, there's definitely movies that have stuck with me.
Aaron 41:26
What would one of those be, do you think?
Anna Phillips 41:28
The one that comes to mind. Like, this is not leech or biology-related. [That's fine.] Um, but In Her Shoes, it's really old. But it had Cameron Diaz in it and Toni Collette, I think. [Yeah, yeah, yeah.] There's these two sisters, and they're trying to come back from a falling out. And they're describing their childhood. And how one was like, ended up having this very carefree life, because they're like, "Oh, you know, our mother was just like, so carefree about everything. So spontaneous. And it was just like, led her to have this very, you know, happy go lucky approach to life. And then the older sister is like, "What are you talking about? Like, Mom was completely irresponsible. Like, I was the one, you know, cleaning up after her the whole time and making sure you were okay." And it's like, these two people had the same experience. But they looked at it from completely different points of view. And I think that's really interesting in life, about how two people can be in the same situation, but they're having a very different experience of it.
Evan 42:29
Yeah. Oh, that's beautiful. Yeah.
Aaron 42:31
And it's a great example. And I suspect, yeah, that some of these leechy qualities, some of the DNA of a leech movie is there.
Anna Phillips 42:39
It may, yeah, but it may not have like four leeches. It may be like two or three. [Yeah. Well there you go!]
Evan 42:43
Yeah, that's great. Most, I mean, most of our movies are somewhere in that range. [Okay.] Awesome. We'll add it to the list. Thank you.
Aaron 42:50
Maybe we can start to wind down by just hearing a little bit about, kind of what is kind of captivating your attention and your research these days. I think I maybe just glanced at some of your more recent articles. One had to do with like leech reproduction. One had to do with a kind of leeches that were... that prey on Arctic fish, maybe? Like, what's captivating your attention right now? What are you learning that's exciting you these days?
Anna Phillips 43:20
Well, so a lot of my PhD-level research was looking at how leeches really are related on a large scale, like between leech families, and looking at these like very old evolutionary patterns, you know, dating back to like Gondwana [Oh wow.] Back in evolutionary time, or geologic time, going back to, you know, hundreds of millions of years. And so a lot of my research now is actually focusing more on the species level. And so it's things that are much more recent. So like, we've been doing this big survey of leeches in New England, for instance, because the leeches of New England were very well studied in the 1800s, early 1900s. But then everyone just kind of said, well, we know what's there and then kind of walked away. There's been a few studies since then, obviously, but not like a really hardcore focus. But since that time, we've had a lot of, for one thing, we brought molecular data to the table. And we've started kind of redrawing some of the species boundaries. And so what we used to call something isn't necessarily the same thing anymore. So that's an interesting way of looking at it. And the other thing is that we don't actually know the exact ranges of all leech species. We don't know, the east, the west, the north and the south of each leech species range. And so going into a place like New England, where it's really well known -- where that leech fauna is really well known -- and then trying to actually draw out and say, "Okay, this extends to this county, in this state." That helps us in terms of, with changing land use, and then also with changing climates and how those distributions are changing over time. To compare it to studies that were done, you know, so long ago. So we're doing some of that. We're doing that with some genomic approaches. And so, so a lot of sequencing at this point has been like a DNA barcoding approach. And we're looking at it with a little bit more of a genomic approach, trying to get as much data from these specimens as possible. And who knows what we're going to learn? Because that means we will be able to ask additional questions based on what we find. So that's one example of some things I've been working on. Yeah, and then otherwise, you never know what comes up. Sometimes leeches from Antarctica feeding on crocodile ice fish, and then sometimes, you know, it's an invasive leech coming from Asia like...yeah.
Evan 45:44
Wow.
Aaron 45:44
Maybe the last leech I want to mention, as we wrap up, is the one you recorded in that "Leeches in the Extreme" article that's from like a very deep sea trench that literally has tentacles growing out of its face?
Anna Phillips 46:00
Right. Yeah, so this was actually the work of one of my colleagues in Ukraine.
Aaron 46:04
Oh my gosh!
Anna Phillips 46:04
Yeah, that was a really incredible finding. They found I think it was like, the deepest record of a leech known. I mean, it's incredible because when you go down in the ocean, you know, there's like -- it's a completely different habitat. I mean, there's no sunlight that's getting through. It's got incredible pressures down there. Then this leech is surviving. And then on top of it, it has these really amazing morphological adaptations of having tentacles for some reason? Or what we'll call tentacles. Like they're leech tentacles, right? It's not like an octopus or anything. [Wow.]
Aaron 46:38
I was Googling and trying to find pictures of it. And I couldn't, but I would love to get my eyes on little leech tentacles. [Yes.]
Anna Phillips 46:48
Okay, I'll see what I can dig up for you. [Thank you.] I mean, another cool worm that has like tentacles are temnocephalans. They're Platyhelminthes, a flatworm. And they occur in tropical areas with -- and they're usually associated with turtles or crabs. Not really sure how that came about. But that's there. I found them twice in my career. And every time we look at them, they were like, "This is the coolest leech ever!" And then about two hours goes by, and we all go "Oh, wait, do remember that really...? Oh, man. You're a temnocephalid. Well, they're still cool." It’s a southern hemisphere group.
Aaron 47:29
Ohhhhh. And they're leech adjacent, right?
Anna Phillips 47:32
They're a completely different phylum. [What?] Yeah, they're different phylum. It's just, they've kind of centered in on a similar mode of being. So their corollaries are actually -- sorry, I'm gonna go off again. [No, it's great]. The closest group of worms to leeches are called branchiobdellidans. These are crayfish worms. And they're actually not parasitic. They're symbiotic. And they're usually really small. And they live on the crayfish on the outside, or they live up under the carapace and the gill chambers. And they use them for reproductive symbiosis. So they use them as a homeland and also to carry out the reproduction so they can't do it anywhere else. So they're in the northern hemisphere. And they're the closest relative to leeches. [Wow.] And they feel the same niche that the temnocephalans are filling in the southern hemisphere, even though temnocephalans are flatworms in a completely different phylum.
Aaron 48:32
Mmm. Flatworms that like crabs and turtles. Got it.
Anna Phillips 48:36
With tentacles. [With tentacles!]
Aaron 48:39
Oh my God. This is mind blowing.
Anna Phillips 48:43
There's a lot of worms out there. There are a lot of different kinds of worms. It's shocking to me. I mean, because we have the national collections here. And like, I get confused all the time. Like, oh, wait, no, it's that, wait. Which group? Okay. I mean, there's multiple phyla. So you know, like in the classification of life, there's kingdom, phylum, class, order, family, genus, species. And so phylum is right up there below kingdom. It's a big grouping.
Aaron 49:10
Wow, I feel like your mind has this enormous archive of very unusual data.
Anna Phillips 49:17
Very, yes, very unusual data. It may not be that enormous of an archive, but it's very unusual data. We do have a database that helps.
Evan 49:29
I was just thinking like, putting on a mug, like "There are a lot of worms. There are a lot of kinds of worms."
Anna Phillips 49:34
I probably need it on a T-shirt at this point, just to be like: Trust me, there are a lot of worms.
Evan 49:40
There's so many worms.
Anna Phillips 49:43
It's more than my career's worth. I mean, I think one cool thing right now and in the world is you probably have more people studying leeches than we have ever had in human history. I mean, actually maybe not human history. I don't want to say that, but like, leech diversity, I'll say. The different kinds of leeches, there's probably more leech biologists right now than there ever have been, which is fantastic. But the problem is so big that we don't have enough. And we desperately need more. I mean for leeches, but then also all the other worms.
Aaron 50:15
So let this be a call to action, all you young aspiring researchers. Yeah, Hear the call, heed the call!
Anna Phillips 50:23
And more to the point, you don't have to go all the way to Rwanda to find new things. We described a new species of leech in 2019 from Southern Maryland, and it's 45 minutes from downtown DC. So yeah, so you don't have to, you know, be into traveling to exotic places or anything. Like there's lots to be learned about leeches here in our backyards. And if it's not about new leech species, it can also be their behavior, what they're feeding on. There's a lot of questions about how leeches survive the different seasons. And like I said, climate change is throwing a wrench in everything. So if somebody, you know -- it doesn't have to be leeches, you could study other worms.
Aaron 51:01
As long as it's worms.
Anna Phillips 51:04
Or you could be a leech enthusiast and just use them as inspiration for your moviemaking. [There you go.]
Evan 51:09
Yes. We will gladly do that. And if there any listeners who wants to learn more from Anna or about the research she does, she's at the Smithsonian. Are there ways to reach out to you, Anna?
Anna Phillips 51:21
Yeah, I'm on the website. So, I'm in the Department of Invertebrate Zoology, with all the other invertebrate people, people who study invertebrates.
Evan 51:30
Awesome. Okay. Well, thank you so much for being with us. It's been a total pleasure. Thank you for taking the time and sharing your expertise with us. What a delight. As always, we want to expand our pond. So if listeners would like to reach out to us on Twitter @leechpodcast, theleechpodcast on Instagram, and theleechpodcast.com, we'd love to hear from you. So on behalf of Banks and Aaron, thank you so much. This is the Leech Podcast. This episode was hosted by Evan Cate. Banks Clark, and Aaron Jones editing by Evan Cate. Graphic designed by Banks Clark. Original Music by Justin Klump of Podcast Sound and Music. And equipment help and consultation from Topher Thomas.