Speaker 1: I've always loved frogs, toads, salamanders, all amphibians, and my
Speaker 1: mother also did, so she would bring us out. We
Speaker 1: didn't really have TV or anything along those lines. We
Speaker 1: spent our entire childhood running around in the woods, which
Speaker 1: is awesome. And she would take us out every spring
Speaker 1: to look at amphibian populations in this local state park
Speaker 1: called Haley Farm, and so we would go out, and
Speaker 1: we knew where to look for the eggs through all
Speaker 1: these little small ponds, and we would go out every
Speaker 1: week and we'd watch the eggs developed tabholes, and then
Speaker 1: those tabholes developed into metamorphs, the little baby frogs, and
Speaker 1: then those would grow up. And we did this my
Speaker 1: entire childhood. When I became a babysitter, that was the
Speaker 1: activity I took all the kids on. So we'd all
Speaker 1: go out and the Haley Farm and look for these amphibians.
Speaker 1: And then I taught special needs camps for years and
Speaker 1: we would do the same thing to bring the kids
Speaker 1: out and we'd look for the eggs. Now, as an adult,
Speaker 1: when I go back, the amphibians are not there. You'll
Speaker 1: see periodically adults, but we just don't see the babies.
Speaker 1: We don't see the eggs, and so they're probably they're
Speaker 1: they're just deeper in the pond or further out into
Speaker 1: the woods. But the populations are not what they used
Speaker 1: to be when I was younger. And it's really sad
Speaker 1: because there's something about going out into the environment and
Speaker 1: finding a frog in the woods that really fosters a
Speaker 1: love for that place like Hayley Farm is one of
Speaker 1: those really special places for me and I think for
Speaker 1: a lot of people. And now that we can't find
Speaker 1: the eggs, you know, kids aren't growing up in those
Speaker 1: state parks finding frogs. They're not finding the eggs, they're
Speaker 1: not trying to catch frogs, which is a huge part
Speaker 1: of my childhood growing up, and I think it is
Speaker 1: with a huge part of what made me become a
Speaker 1: concentration disease ecologists, because I loved that when I was younger,
Speaker 1: and it's just not a thing anymore for kids.
Speaker 2: Hi, I'm erin Welsh and I'm erin oman Updyke and.
Speaker 3: This is this podcast will Kill You Today.
Speaker 2: We're talking about Kittred Kittred, and you just heard a
Speaker 2: fabulous first hand account of some of the terrible effects
Speaker 2: that Kittred has had on Amphibian communities by our friend
Speaker 2: Tagan McMahon, Doctor Tagan McMahon. I should introduce her properly.
Speaker 3: And you will hear it more from her later in
Speaker 3: the episode, because she was so kind as to share
Speaker 3: some of her expert experience and knowledge on the subject,
Speaker 3: so we didn't have to do as much work.
Speaker 2: Yes, no, not kidding, though at least I didn't have to.
Speaker 3: Only kind of kidding. But before we get there, we
Speaker 3: have one very important thing to do, and that means.
Speaker 2: It's quarantine time time.
Speaker 3: What are we drinking this week?
Speaker 2: Today? We're drinking simply croaked.
Speaker 3: We shouldn't be laughing at this. It's not funny, but
Speaker 3: it's not funny punny, I'm tickled at the name. What's
Speaker 3: in croaked?
Speaker 2: There is mango puree, a bit of lime juice, some
Speaker 2: bubbly fizz water and rum of.
Speaker 3: Course delicious run a boil, oh if if you can
Speaker 3: grab it.
Speaker 2: And the key ingredient in this particular beverage is just
Speaker 2: a few sprinkles of chia.
Speaker 3: Seeds to look like frog eggs.
Speaker 2: You guys, I love it. We'll post the full recipe
Speaker 2: for this quarantini as well as our non Alcoholic Place
Speaker 2: Barta on our website and all of our social media channels,
Speaker 2: so you can find them there. Do you have any business.
Speaker 3: Erin I don't think so.
Speaker 2: We have merch. We have merch, go look at it.
Speaker 2: You can find our merch at our website. This podcast
Speaker 2: will kill you dot com by clicking on merch. And
Speaker 2: we've got t shirts and mugs and pins and the
Speaker 2: most important of all, soap. Soap we have It smells
Speaker 2: so good. I have a bar in my bathroom right now,
Speaker 2: and every time that I walk in there, I'm like,
Speaker 2: what smells so good? And it's the soap. Every single time. Legitimately,
Speaker 2: it makes the whole bathroom smell good. I didn't know
Speaker 2: soap could do that.
Speaker 3: Packaging is incredible.
Speaker 2: Okay, okay, so enough of that.
Speaker 3: All right, Kittredgy hit me with it.
Speaker 2: I'll hit you with it in just a minute, Okay,
Speaker 2: So listen, kittred First, off is a fungus.
Speaker 3: Our first fungus, Our first fungus.
Speaker 2: We like briefly talked about fung gui on the Biology
Speaker 2: of Superheroes podcast. Right, that's right.
Speaker 3: We talked about court.
Speaker 2: Aceps, cordyceps. Okay, but this is our first fora into
Speaker 2: the fun guy. Okay, so let's talk about this fungus
Speaker 2: itself first. The fungus that causes the disease known as
Speaker 2: kytridio micosis in amphibians is called batray coquittrium dendro but titus.
Speaker 3: I'm glad that you attempted that, because.
Speaker 2: I looked it up and I wrote out a phonetic
Speaker 2: spelling for myself. Yeah, I know.
Speaker 3: Can you can you quickly send that over to me
Speaker 3: because I need to do it.
Speaker 2: Later, Okay, battray coquittrium dendro bade titus, Okay, dendro get
Speaker 2: to it. You could call it b D.
Speaker 3: And I do.
Speaker 2: Okay, And I really hope that this isn't stepping on
Speaker 2: your history toes too much, Aaron. But I texted you
Speaker 2: about this because I got so excited and it blew
Speaker 2: my mind so much because we just did Giardia, which
Speaker 2: I said correctly, and we didn't Giardia I did, and
Speaker 2: it blew my mind in that episode that that parasite
Speaker 2: wasn't fully classified until like the late eighties.
Speaker 1: Right.
Speaker 2: B D wasn't described as a species until nineteen ninety nine.
Speaker 3: Yeah what? Yeah, Oh my gosh, I did not know
Speaker 3: that at all.
Speaker 2: It was thrilling information. Yeah, and there's another species that
Speaker 2: infects salamanders, battery Coquetrium salamandrivorians that was described in twenty thirteen.
Speaker 4: Uh huh, oh my god, this is the history is
Speaker 4: still being written. That's oh big time. Okay, So this
Speaker 4: is a fungus. We'll call it B D or probably
Speaker 4: a lot of times through this episode, we might just
Speaker 4: call it kittrid. But I do want to point out
Speaker 4: that there's a lot of other fungi in the group
Speaker 4: known as kittridio mycoda. So even though we'll be probably
Speaker 4: bad biologists and call it kittrid, I might slip up
Speaker 4: and call it kittrid. There are a number of different
Speaker 4: other kittrid fungi, many of which are free living and
Speaker 4: happily exist in the environment, digesting cellulose and kitan and keratin.
Speaker 2: Ding ding ding. That word's gonna come back. Other kittreds
Speaker 2: are parasitic on plants or algae or other invertebrates. But
Speaker 2: the one that we're focusing on today is the only
Speaker 2: I guess two species B D and B. Sal that
Speaker 2: are known to infect vertebrates, specifically amphibians. Okay, so today
Speaker 2: we're talking about an amphibian. Fur Fungi have very cool
Speaker 2: life cycles in general, and kitrid Kytridiomycota fungi are no exception.
Speaker 2: They have two life stages, the zospore and the zo sporangium.
Speaker 2: So the zospore is like a spore, so it travels
Speaker 2: through the environment, that's the point of it. And it
Speaker 2: happens to have an adorable little flagellum and it can swim.
Speaker 2: So the zospoor stage swims through water. It doesn't go
Speaker 2: very far, We're talking like a few centimeters, but it
Speaker 2: does swim, and it responds to chemotactic signals, so it
Speaker 2: actually can swim directionally towards a host, in this case,
Speaker 2: an amphibian. When it finds an amphibian, it releases a
Speaker 2: bunch of proteolytic enzymes. So it releases a bunch of
Speaker 2: stuff that digests the protein on the skin of the amphibian,
Speaker 2: and then it burrows its way into the skin of
Speaker 2: this let's call it frog.
Speaker 3: What cues is it using to find the host?
Speaker 2: That's a good question that I don't entirely know the
Speaker 2: answer to. It's a really good question, but they know that, Like,
Speaker 2: it's not just swimming at random. It swims directionally towards
Speaker 2: the frogs. But I'm not sure what about the frogs, Like,
Speaker 2: what are they releasing that they're swimming towards? Great question.
Speaker 2: So once it's at the frog, it burrows its way
Speaker 2: into the skin. It forms a little cyst, and then
Speaker 2: it forms the sessile or the non motile stage, the
Speaker 2: zosporangia underneath the skin of this little frog. That zosporangia
Speaker 2: will grow and then produce additional zo spores which will
Speaker 2: burst forth from the skin and swim along their way,
Speaker 2: and those zospores can either reinfect the same host in
Speaker 2: a new spot, or if they're close enough to another frog,
Speaker 2: they can infect a new host. Today, life cycle complete.
Speaker 3: And about how long is this all taking place?
Speaker 2: Oh gosh, Well, I know that the incubation period from
Speaker 2: when the zospor first infects to when the frog starts
Speaker 2: showing symptoms are between ten and eighteen days. Okay, So
Speaker 2: my guess is that that's about the timeframe that it
Speaker 2: takes for them to start shedding.
Speaker 3: And I would assume it it's variable depending on frog
Speaker 3: species and temperature, or amphibian species and temperature and et cetera,
Speaker 3: et cetera very variable.
Speaker 2: Yeah, okay, so let's talk about the symptoms of a
Speaker 2: kittrid kytritiomycosis infection.
Speaker 3: This is gonna make me sad.
Speaker 2: It's it's so sad. It hit me in the feels
Speaker 2: this one. So you can tell by the way that
Speaker 2: I describe the life cycle that this fungus it's pretty
Speaker 2: much just infecting the skin of these amphibians. So human
Speaker 2: listeners might be thinking something along the lines of how
Speaker 2: can a simple skin infection be so detrimental to an amphibian?
Speaker 2: It's just skin. Do you think anyone would say that,
Speaker 2: Maybe they would.
Speaker 3: I don't know.
Speaker 2: But for anyone who's not familiar with frogs and amphibians,
Speaker 2: their skin is not just a barrier between the frog
Speaker 2: and the outside world. It's not for us either, but
Speaker 2: in frogs it's an especially important organ. It's part of
Speaker 2: how frogs breathe, it's part of how they hydrate, how
Speaker 2: they thermoregulate, how they osmo regulate. So it's a very
Speaker 2: critical organ. Okay, So any kind of skin infection in
Speaker 2: a frog, you can assume is going to be bad
Speaker 2: news bears, and that is very true in kittrid. However,
Speaker 2: because B. D. Chytrid can infect so many different species
Speaker 2: of amphibians, the symptoms really do vary a lot based
Speaker 2: on the species and how serious the infection is varies
Speaker 2: hugely across species, and actually, Tagan, we'll talk a little
Speaker 2: bit more about that, because we don't fully understand why
Speaker 2: it is that some species seem to handle infection so
Speaker 2: much better than other species. But we can talk about
Speaker 2: some of the generalized symptoms that you see in a
Speaker 2: kytrideo micosis infection. First off, what's very interesting is that
Speaker 2: you don't see a lot of inflammation, so the frogs
Speaker 2: themselves aren't mounting a big inflammatory response when they get
Speaker 2: infected with this fungus. But what you do get is
Speaker 2: something called hyper keratosis, which means that you're making a
Speaker 2: whole bunch more keratin, which is kind of the protective
Speaker 2: protein that we have in our skin as well. It's
Speaker 2: the toughest, outermost layer of skin, which for a frog,
Speaker 2: because their skin has to be able to interact with
Speaker 2: the environment so much, this is especially bad because that
Speaker 2: means that this thick, extra extra keratinized layer is not
Speaker 2: going to be as permeable to water or air or electrolytes.
Speaker 3: That's really interesting.
Speaker 2: Yeah, I know that. Why didn't neither? Yeah, And then
Speaker 2: what you also get very very commonly is sluffing of
Speaker 2: the skin, So this skin will just start to slough
Speaker 2: off in sheets, which is really sad. You can get
Speaker 2: ulceration and like multiple cyst formation, but you don't always.
Speaker 2: The skin sloughing is kind of more common than this
Speaker 2: ulceration formation. Often also, the skin will become very discolored.
Speaker 2: So you might have seen classic photos of frogs infected
Speaker 2: with kittred that are bright red on their belly and
Speaker 2: their legs. So that's really common, is for their bellies
Speaker 2: to become disccolored, and it's also very in common. It's
Speaker 2: very common that they get infected at the highest rates
Speaker 2: or the most intense infection on their bellies and their legs,
Speaker 2: like the undersides, which to me kind of makes sense
Speaker 2: because this is a fungus that's in the environment and
Speaker 2: in the water specifically, so that's kind of the part
Speaker 2: of the frog that's probably in contact with water the
Speaker 2: most and in contact with the soil the most, right,
Speaker 2: But it can infect any part, any keratinized part of
Speaker 2: the frog.
Speaker 3: But does the infection tend to be localized in that
Speaker 3: way or is it pretty much systemic at a point?
Speaker 2: Well, that's an interesting question. So it's not systemic in
Speaker 2: that it doesn't travel throughout their body. This is a
Speaker 2: very localized skin infection. The zosporangia can produce like these
Speaker 2: I don't know if rhizomes is the proper word, but
Speaker 2: they can sort of spread out a bit where they infect,
Speaker 2: but really they also just produce a lot of spores
Speaker 2: that auto infect that same host on other parts of
Speaker 2: the skin. So you end up with really high burdens
Speaker 2: of infection where you have spores infecting all over the skin,
Speaker 2: but it doesn't travel like through their bloodstream, it doesn't
Speaker 2: invade their organs, et cetera. And that's I'm going to
Speaker 2: talk a little bit more about that in a minute,
Speaker 2: because it's a really interesting part of the story. Yeah. Yeah,
Speaker 2: So any and all parts of the skin can get infected.
Speaker 2: And then what you see happening in addition to all
Speaker 2: these skin changes is that the frogs become very lethargic.
Speaker 2: They stop seeking protection, they stop hiding during the day,
Speaker 2: so you can find them just sitting out and about.
Speaker 2: They're less responsive to stimuli. So if you try and
Speaker 2: get them to jump or to do something, they just
Speaker 2: kind of don't. They just don't really respond, and they
Speaker 2: can sit in a very kind of characteristic position where
Speaker 2: they're sitting out and their hind legs, their jumper legs
Speaker 2: are not poised underneath them like a frog ought to be,
Speaker 2: like ready to bounce at any second. They hang their
Speaker 2: kind of loose and gangly and they hold them away
Speaker 2: from their body. Isn't that sad? It's really sad, just
Speaker 2: this little loose like wop of a frog.
Speaker 3: Well just no like yeah, no willingness to yeh ever, yeah, ability.
Speaker 2: And then then they die. Yeah, sorry, there's no easy
Speaker 2: way to say that. So then they die. And what's
Speaker 2: interesting is that one very common cause of death is
Speaker 2: actually heart attack, ty, any little froggy heart attack?
Speaker 3: Is this because they can't regulate water?
Speaker 2: Oh look at you airon you're so smart?
Speaker 3: Yeah.
Speaker 2: So again, this is an infection that's not actually invading
Speaker 2: any organs in general. It can in some cases, but
Speaker 2: in general it's just in the outermost layer of this
Speaker 2: frog's skin. And so we don't fully understand exactly how
Speaker 2: this disease ends up killing frogs. But what it does
Speaker 2: seem to do, according to a twenty eighteen paper that
Speaker 2: I found, is that it causes widespread metabolic imbalance. So
Speaker 2: the electrolytes of the frogs get completely messed up because
Speaker 2: they're not able to osmo regulate through their skin like
Speaker 2: they're supposed to. They can't regulate the water and electrolytes
Speaker 2: moving in and out of their skin. And when that happens,
Speaker 2: other organs can get messed up. So then other important
Speaker 2: metabolites that you're body would normally produce, like say your
Speaker 2: liver would normally produce these certain metabolites that liver the
Speaker 2: liver can't do that because the other electrolytes are so
Speaker 2: messed up. Does that make sense? So while kittred itself
Speaker 2: doesn't invade frog's livers or hearts, the osmodic deregulation that
Speaker 2: it causes just by infecting the skin to such a
Speaker 2: degree ends up affecting processes in their internal organs and
Speaker 2: that's what ends up causing death.
Speaker 3: That makes sense and horrible sad sense, Yeah.
Speaker 2: Horrible and sad, And it's it was really interesting to
Speaker 2: sort of do the research on this because it's so recent.
Speaker 2: Because a lot of times when I'm trying to figure out,
Speaker 2: you know, what's the path of physiology of a disease,
Speaker 2: I just I find a paper that's relatively recent, like
Speaker 2: the last twenty years, and they've got pretty much an answer.
Speaker 2: But in this one, if you go back just five
Speaker 2: or ten years, it's all, here's our hypothesis, here's the
Speaker 2: best guess we have. And so it's only from these
Speaker 2: really really recent papers, like this twenty eighteen paper, which
Speaker 2: I will post on our website, where they actually found
Speaker 2: sort of evidence of this. It's still not entirely clear
Speaker 2: how this happens, but there is good evidence for this
Speaker 2: widespread electrolyte imbalance.
Speaker 3: I would bet that that's also just also a factor
Speaker 3: of it being a wildlife disease versus a human disease.
Speaker 2: Definitely definitely funding research, etc. Right, And another thing I
Speaker 2: noticed is that so much of what we study in
Speaker 2: wildlife diseases compared to human diseases is all population level
Speaker 2: rather than individual level. So like the disease process that's
Speaker 2: happening inside each individual frog is not studied to the
Speaker 2: same extent as a disease in humans might be. If
Speaker 2: that makes sense.
Speaker 3: We don't have we lack the case studies in wildlife, Yeah,
Speaker 3: exactly these cases.
Speaker 2: Yeah, yeah, So that's pretty much the biology. The other
Speaker 2: thing I did want to say that I think is
Speaker 2: interesting is that so BD kittred amphibian Kittrid only infects
Speaker 2: keratinized epithelium, so that means that actually tadpoles aren't infected,
Speaker 2: So tadpoles actually can survive in areas that have BD.
Speaker 2: The only part of a tadpole that has keratin is
Speaker 2: the mouth parts, so that's the only part that b
Speaker 2: D can potentially infect. But then as soon as a
Speaker 2: tadpole starts to undergo metamorphosis, as soon as they start
Speaker 2: to change into adults, then they've got that keratin, then
Speaker 2: they can be infected, so even really early early frogs,
Speaker 2: but just not tadpoles specifically.
Speaker 1: Right.
Speaker 2: But what's also very interesting is that a lot of
Speaker 2: free living Kittrid fungus also feeds on keratin, and so
Speaker 2: it's hypothesized that that's exactly what this fungus is feeding
Speaker 2: on in the frogs, and it's interesting that it's causing
Speaker 2: this hyperkeratotic response where the frogs they're not mounting an
Speaker 2: immune response, they're not coming in and fighting off this infection,
Speaker 2: but rather they're making more and more keratin, and that's
Speaker 2: potentially what this fungus is feeding on. So it's like
Speaker 2: the fungus is creating the optimum environment for itself to
Speaker 2: survive in this frog.
Speaker 3: Right, I mean, it's it's ingenious. Yeah, and huh, I
Speaker 3: know where what else is keratin? Tell me more about keratin.
Speaker 2: So, keratin is the protein. It's all of our skin,
Speaker 2: Like any skin that you see, it's all keratinized. Your
Speaker 2: hair is keratin, your nails are keratin. It's a protein
Speaker 2: that makes it's like a very tough outer protein. So
Speaker 2: our skin as it grows and moves, like from the
Speaker 2: basal layers and then it moves up, it becomes keratinized.
Speaker 2: So by the time that it reaches our outside environment,
Speaker 2: it's like completely just mostly keratin. There's not really any
Speaker 2: cell left.
Speaker 3: So why amphibians and not other animals.
Speaker 2: Great question, it's a really good question. I'm sure that
Speaker 2: it's not the exact same keratin. There's a lot of
Speaker 2: different types of keratin, so it might just be that
Speaker 2: they can infest a very specific form of keratin. That's
Speaker 2: a really good question though.
Speaker 3: H Yeah, interesting.
Speaker 2: Yeah, so that's the biology.
Speaker 3: Oh that was it? What do you think? That was great?
Speaker 2: It was so fun to learn about. I knew nothing
Speaker 2: about Kittrid. Oh yeah, no, I.
Speaker 3: Knew nothing except sort of like the broad sweeps.
Speaker 2: Of it, right, Like I knew it's real bad for
Speaker 2: frogs and it's causing widespread havoc and that's literally and
Speaker 2: like I've seen pictures of ponds where Kittrid is just
Speaker 2: you know, all these dead frogs. That's all that I knew.
Speaker 1: Yeah.
Speaker 2: So, oh so, Aaron, tell me, how did we get here?
Speaker 2: What's the history of this thing?
Speaker 3: Okay, I'll see what I can do.
Speaker 2: Right after this break.
Speaker 3: In the nineteen eighties, all over the world, the forest
Speaker 3: started to go silent. Oh no, it started to become static.
Speaker 2: Still.
Speaker 3: This was not the vibrant, dynamic forest that we were
Speaker 3: used to. Something many somethings were missing, and it didn't
Speaker 3: go unnoticed. Herpetologists across different continents began talking amongst themselves.
Speaker 3: Where have the frogs gone? Where have the salamanders gone?
Speaker 3: Where have the toads gone? Where there used to be
Speaker 3: untold numbers of frogs, toads, salamanders, amphibians, Now there were none.
Speaker 3: Even stranger were the circumstances of this sudden disappearance. Amphibians
Speaker 3: were going missing in habitats of all kinds, from urban
Speaker 3: streams to remote, highly protected conservation regions, and often there
Speaker 3: were no bodies to be found. What Yeah, they just
Speaker 3: sort of disappeared, which makes sense, okay. In other places,
Speaker 3: the sad carcasses of amphibians piled up, which was in
Speaker 3: itself maybe even more bizarre because in places like the tropics,
Speaker 3: something as small as a frog can be quickly dismantled
Speaker 3: by ants or dispatched by a bird within a matter
Speaker 3: of minutes or hours, So the sight of these corpses
Speaker 3: was maybe even more worrying than their absence. What could
Speaker 3: be causing such widespread devastation, Climate change, habitat destruction, environmental toxins,
Speaker 3: and infectious diseases were all the immediate culprits. Finding out
Speaker 3: what was causing these amphibian die offs was top priority
Speaker 3: if there was any hope of saving even some of
Speaker 3: the species. Extinction happens, but not often like this. This
Speaker 3: is probably the largest extinction event that modern humans have
Speaker 3: been witnessed to so far. Wow, maybe this is pessimistic
Speaker 3: of me. But I don't think it'll be the last
Speaker 3: one we see in our lifetime.
Speaker 2: You're probably right.
Speaker 3: Yeah, let's talk about amphibians. Okay, what does the word
Speaker 3: amphibian mean?
Speaker 2: Oh, good question. Tell me.
Speaker 3: It comes from the Greek for double life, oh, which
Speaker 3: is a nod to their close dependence on water and
Speaker 3: moisture and sort of their transformation over their life cycle.
Speaker 2: Cool.
Speaker 3: Many species of amphibians need water to complete their life cycle.
Speaker 3: Tadpoles swimming around in little ponds, stuff like that. But
Speaker 3: that's not the only way that eggs develop into tadpoles
Speaker 3: and then frogs. So frog eggs and amphibian eggs don't
Speaker 3: have a hard shell like that of a bird, so
Speaker 3: they have to be kept moist or they'll dry out.
Speaker 3: Frogs can do that by laying them in streams or
Speaker 3: ponds or temporary pools, but some will make their own
Speaker 3: little foam nest to lay eggs. Some carry the eggs
Speaker 3: around on their backs or on their legs, and some
Speaker 3: carry their eggs in their stomachs, eventually giving birth to
Speaker 3: little frogs out of their mouths. Oh my god, it's
Speaker 3: so cute, Or at least they used to. Because the
Speaker 3: two species that did this stomach brooding went extinct in
Speaker 3: the nineteen eighties and haven't been seen since. Oh, I know,
Speaker 3: it's cruel of me.
Speaker 2: That was really cruel. Are there any in captivity?
Speaker 4: No?
Speaker 1: Yeah.
Speaker 3: As of July sixteenth, twenty nineteen, when we're recording this episode,
Speaker 3: there are eight and forty three species of amphibians, and
Speaker 3: that includes frogs, toads, salamanders, and sicilians, which don't have
Speaker 3: any limbs and kind of look like giant worms or
Speaker 3: very slippery small snakes. They're kind of cute in a
Speaker 3: weird way, kind of creepy cute.
Speaker 1: I don't know.
Speaker 3: Frogs and toads make up the biggest chunk of this,
Speaker 3: and new species of amphibians are being discovered all the time,
Speaker 3: all the time. So of these over eight thousand amphibian species,
Speaker 3: five hundred and one, which is around six point five percent,
Speaker 3: have faced serious declines due to kittred, with at least
Speaker 3: ninety possibly one hundred and twenty two confirmed or presumed
Speaker 3: to be extinct in the wild. God Dang over the
Speaker 3: course of a couple of decades. Right according to the
Speaker 3: authors of one of the papers I read, we are
Speaker 3: witnessing quote the most spectacular loss of vertebrate biodiversity due
Speaker 3: to disease in recorded history.
Speaker 2: Wow, it's.
Speaker 3: Unprecedented, yeah for us to observe. Amphibians have been around
Speaker 3: since before there were humans, before there were mammals, before
Speaker 3: there were dinosaurs. There are amphibian species on all continents
Speaker 3: except Antarctica. There are species that live in the desert,
Speaker 3: like the sand hill frog of Australia, ones that live
Speaker 3: on mountains, ones that live in rainforests, ones that live
Speaker 3: above the Arctic circle like frog.
Speaker 4: Yeah.
Speaker 2: Oh yeah, I knew that, but it's still crazy.
Speaker 3: Ones that literally freeze solid during winter and emerge again
Speaker 3: in the spring, little spring peepers. The diversity of amphibians
Speaker 3: is amazing, and their survivors they have gone through massive
Speaker 3: extinction events and lived to tell about it. But their
Speaker 3: long and incredible existence may be coming to an end,
Speaker 3: and the biggest reason is us humans. It's maybe a
Speaker 3: bit difficult to say exactly when the great decline of
Speaker 3: amphibians began, but I can tell you when it started
Speaker 3: to be noticed at least, and that was in the
Speaker 3: nineteen eighties, and similar to how Tegan described it was
Speaker 3: a pretty drastic shift researchers were coming back empty handed
Speaker 3: from collecting trips where they once could barely avoid stepping
Speaker 3: on frogs. Amphibian populations had been declining over the past
Speaker 3: century due to things like overhunting, habitat destruction, etc. But
Speaker 3: it was the recognition that it was happening globally and
Speaker 3: rapidly that really caught science into the tension. In September
Speaker 3: nineteen eighty nine, the first World Congress of Herpetology led
Speaker 3: to a massive gathering of herpetologists from all over the world.
Speaker 2: Just imagine that room, man, herpetologists are.
Speaker 3: Some of the coolest people.
Speaker 2: I was just thinking, I was saying this to myself
Speaker 2: when I was researching this. I was like, of all
Speaker 2: of the you know, like ornithologists, entomologists, herpetologists, ichthyologists, I
Speaker 2: feel like herpetologists are I would go to that international congress.
Speaker 3: It would be I mean, I'm not sure, Like I
Speaker 3: think it would be the most fun.
Speaker 2: It would be pretty fun.
Speaker 3: I feel like they know how to party, but I
Speaker 3: don't know. So at this conference that this World Congress
Speaker 3: of Herpetology, researchers there began to talk amongst themselves about like,
Speaker 3: oh yeah, I really had a hard time finding this
Speaker 3: my study species this year, and someone would be like, oh,
Speaker 3: me too, But I was doing research in this other country,
Speaker 3: this other continent, And so one instance of not being
Speaker 3: able to locate your study organism might not be that
Speaker 3: surprising because fieldwork is unpredictable and sometimes the animals you
Speaker 3: want to find aren't where you expect to find them,
Speaker 3: and that just happens. But this was that times a
Speaker 3: thousand researcher after researcher had a story about the unexpected
Speaker 3: disappearance of their study species, and people started to pick
Speaker 3: up on these not being isolated events but part of
Speaker 3: maybe like a larger crisis, one that was taking place
Speaker 3: across the entire globe. And after this congress, herpetologists wasted
Speaker 3: no time. They got right into action. They started holding
Speaker 3: workshops to present the most likely causes of the amphibian decline,
Speaker 3: and then they proposed a plan of action to save
Speaker 3: the frogs. So this plan had basically three focuses. One
Speaker 3: save the amphibians conservation, two find out what was killing
Speaker 3: them investigation, and three tell people about it education, because
Speaker 3: unless you get people who are not researchers interested and
Speaker 3: passionate about the subject, it's going to be an uphill battle,
Speaker 3: even more than it already is. Absolutely so to have
Speaker 3: any shot at long term success with conservation, scientists had
Speaker 3: to get work on uncovering what was causing this rapid decline.
Speaker 3: What were the clues left behind. The first was that
Speaker 3: the species that were suffering were the most similar ecologically.
Speaker 3: They bred or lived near streams or other water sources,
Speaker 3: and had to spend a significant amount of their lives
Speaker 3: in contact with water. The second was that it was
Speaker 3: happening rapidly, but still in like a wave like pattern.
Speaker 3: It would start in one geographic area and then go
Speaker 3: upwards directionally or go in some direction. The third was
Speaker 3: the rate of decline, which was super fast, really fast.
Speaker 3: Within a few years, the population went from normal or
Speaker 3: at least what was maybe could be perceived as normal,
Speaker 3: to empty done extinct. The fourth was in the bodies
Speaker 3: of the amphibians themselves. So in this book that I read,
Speaker 3: they mentioned how organ that there were some organs that
Speaker 3: showed widespread necroses, And then there was just the behavior
Speaker 3: of the diseased frogs themselves, acting sluggish and not being
Speaker 3: able to move. Yeah, And the fifth thing is that
Speaker 3: these are a lot of clues was that there were
Speaker 3: some species that seemed to escape the effects of whatever
Speaker 3: this was while their neighbors died in droves. So all
Speaker 3: of these things together kind of shouted to researchers, this
Speaker 3: is an infectious disease. All of those things are very
Speaker 3: characteristic of a widespread virulent pathogen. A couple of years
Speaker 3: after this disease hypothesis had been fully fleshed out, researchers
Speaker 3: across different continents detected a fungal pathogen on the skin
Speaker 3: of dead and dying amphibians. Amphibians from different continents, from Australia, Europe,
Speaker 3: North America all seemed to harbor this pathogen. And so
Speaker 3: the researchers who were like, hey, so do you do
Speaker 3: you see this thing? Because I have a fungus on
Speaker 3: my frog. Do you have a fungus on your frog?
Speaker 2: I just wanted to say that Aaron is using her
Speaker 2: phone hands like yes, calling someone on the phone to
Speaker 2: chat across global waters.
Speaker 3: Well, and they didn't have to chat across global waters
Speaker 3: much longer. They were like, you know what, let's meet
Speaker 3: up in person. Let's take a real peak at this.
Speaker 3: So they met herpetology meeting another herpetology meeting, this one
Speaker 3: in Da Da Champagne, Illinois.
Speaker 2: Not ah, yeah, stop it.
Speaker 3: In nineteen ninety eight, a bunch of researchers who've had
Speaker 3: found this pathogen gathered in Champagne to compare their findings
Speaker 3: to say, is this fungus the same? Is my fungus
Speaker 3: the same as your fungus?
Speaker 2: That's adorable. I also should say I didn't mean to
Speaker 2: throw shade on the other ologists earlier. They're all going
Speaker 2: to get in trouble for they know, I know, right,
Speaker 2: especially for like other entomologists. It's cool. We're all cool nerds.
Speaker 3: Everyone's cool in their own nerdy way. That's just how
Speaker 3: it is.
Speaker 2: Yes, anyways, we're in Champagne. We're comparing fungi.
Speaker 3: I love it, well, the fungi. The I always say fungi, but.
Speaker 2: I think it's supposed to be fungi. That's what my
Speaker 2: high school biology teacher would kill me for saying fungi.
Speaker 2: Maybe that's why I say it.
Speaker 3: But these fungi were all the same. They looked and
Speaker 3: they were like, how but how is this possible? These
Speaker 3: are the same These look to be the same species.
Speaker 3: And they were like, okay, well, what kind of fungi
Speaker 3: is this kittrid And that's not that surprising, maybe because
Speaker 3: kittred is everywhere, so you know, okay, that makes a
Speaker 3: little bit of sense. But like you said, this was
Speaker 3: unprecedented in its ability to infect and cause disease and vertebrates.
Speaker 3: And the other thing was that it looked brand new,
Speaker 3: like this was a different kind of kittred, and so
Speaker 3: not only was a new species named, it was a
Speaker 3: new entire genus that was created to house this bd.
Speaker 2: That's so exciting. Ugh, yeah, so exciting.
Speaker 3: This kittrid fungus seemed to be an unstoppable force. It
Speaker 3: tore through populations and then just sat there waiting, because
Speaker 3: kittred doesn't need amphibians to survive, it's content to just
Speaker 3: chill waiting. Finding out what was responsible for at least
Speaker 3: a good bit of the amphibian declines was great news, right,
Speaker 3: but it also raised a ton more questions and even
Speaker 3: some skepticism. No single pathogen had been the cause of
Speaker 3: so many extinction events or population declines in modern history,
Speaker 3: and blaming the decline on kittred might make people ignore
Speaker 3: the other causes of amphibian decline, such as environmental pollutants
Speaker 3: and climate change, and it still left this massive question
Speaker 3: of how do we stop it. The story of amphibians
Speaker 3: and kittred shouldn't be looked at in isolation because it's
Speaker 3: raised all kinds of questions about what the role of
Speaker 3: humans is in conservation intervention. Some people have argued that
Speaker 3: kittred is a natural pathogen, so maybe these extinctions and
Speaker 3: population declines are natural as well. Yeah, that expression you're making,
Speaker 3: I'm also like you, No, I don't buy that.
Speaker 2: Highly skeptical expression for everyone.
Speaker 3: Well, because what it does is that, I mean, that
Speaker 3: viewpoint fails to consider or acknowledge the role that humans
Speaker 3: have played in the spread of kittred around the globe.
Speaker 2: Like diseases don't just pop up everywhere at once, out
Speaker 2: of nowhere. Nope, that's not yeah, nope.
Speaker 3: And there's also some catrid emergence and climate change seem
Speaker 3: to be in some cases acting in conjunction with each other.
Speaker 3: So yeah, again, and humans, this is human induced climate change.
Speaker 3: This is humans have caused climate change. Yeah, yeah, that's
Speaker 3: a fact anyway. But the other reason that you can't
Speaker 3: tell the story of amphibian decline as one single event
Speaker 3: is because it's part of a massive and terrifying trend
Speaker 3: that's happening globally right now. We're in the middle of
Speaker 3: and the cause of the sixth extinction. I want to
Speaker 3: talk just a little bit about extinctions.
Speaker 2: Good, let's make this a more depressing episode.
Speaker 3: I mean, one of my favorite, one of my favorite
Speaker 3: courses in college was called Dinosaurs and Disasters. So this
Speaker 3: is really gone back to my my roots.
Speaker 2: Yeah.
Speaker 3: Okay, So you might have heard this term the sixth
Speaker 3: extinction or the Holocene extinction used a lot quite a
Speaker 3: bit lately, particularly in talking about climate change impacts or
Speaker 3: exploitation of natural resources, and often along with the word anthropiscene.
Speaker 2: But what is it?
Speaker 3: What is the sixth extinction? Basically, since the first vertebrates evolved,
Speaker 3: there have been five massive extinction events, and we can
Speaker 3: see these in the fossil record. The first one took
Speaker 3: place four hundred and fifty million years ago, which is
Speaker 3: just an incomprehensible amount of time. Yeah, And the most
Speaker 3: recent one happened at the end of the Cretaceous period
Speaker 3: around sixty five million years ago. That's the one that
Speaker 3: wiped out all the dinosaurs and pterosaurs and plesiosaurs and
Speaker 3: all the other cool animals, and based on the population
Speaker 3: declines and extinction rates of not just the amphibians but
Speaker 3: many other species, some researchers believe that we are in
Speaker 3: the midst of the sixth Great Extinction event, and the
Speaker 3: really is the only debate that seems to be left
Speaker 3: is where to actually put the starting point of that,
Speaker 3: because a lot of people believe that humans were responsible
Speaker 3: for the extinction of the prehistoric megafauna like the giant
Speaker 3: ground sloth and mastdons and you know, all of the
Speaker 3: amazing cave bears and Irish elk all I love parents.
Speaker 2: Face is getting so sad talking about this, you guys, I.
Speaker 3: Wish I could time travel so much. But what makes
Speaker 3: a mass extinction a mass extinction? Because animals do go
Speaker 3: extinct for various reasons occasionally, by looking at the fossil record,
Speaker 3: paleontologists can estimate about how many species of a certain
Speaker 3: group of animals, like let's say mammals go extinct over
Speaker 3: a long period of time, and that is what we
Speaker 3: would call a background extinction rate, just a normal baseline
Speaker 3: level of extinction. And it's when that extinction rate skyrockets
Speaker 3: beyond the normal background rate that we call it a
Speaker 3: mass extinction, particularly if there are multiple groups that are
Speaker 3: undergoing higher extinction rates at the same time. So I'm
Speaker 3: going to borrow a metaphor from palaeontologist Michael Benton. He
Speaker 3: suggests you think of it as the tree of life.
Speaker 3: As the tree grows, you have little twigs or branches
Speaker 3: that may break off along the way just as part
Speaker 3: of the growth process, part of the normal weathering, and
Speaker 3: a mass extinction event is like a tornado coming through
Speaker 3: and ripping off an entire half of the tree, or
Speaker 3: huge branches at random places that won't grow back. The
Speaker 3: background extinction rate for amphibians is hard to estimate since
Speaker 3: there are fewer fossils than there are for something like mammals,
Speaker 3: but researchers think it's very low, probably around one amphibian
Speaker 3: species going extinct every thousand years.
Speaker 2: Wow. Whoa, oh that's yeah, oh dear.
Speaker 3: The extinction rate currently is estimated to be two hundred
Speaker 3: and eleven times higher than the background rate, or if
Speaker 3: you take into account endangered species, as much as forty
Speaker 3: five thousand times higher.
Speaker 2: Oh oh no, yeah, assuming that endangered species are very
Speaker 2: unlikely to bounce back and are going to go extinct eminently.
Speaker 3: Yeah right, Yeah, Amphibians are the most endangered class of animals.
Speaker 3: And even though this episode is about kittrid and amphibians,
Speaker 3: I want to bring us even further down by mentioning
Speaker 3: that they're not the only ones in an extinction crisis.
Speaker 3: So this is basically taken pretty much verbatim from the
Speaker 3: sixth Extinction and estimated one third of rebuilding corals, one
Speaker 3: third of freshwater mollusks, a third of sharks and rays,
Speaker 3: a quarter of all mammals, a fifth of all reptiles,
Speaker 3: and a sixth of all birds are headed towards extinction.
Speaker 2: Oh no, oh, yeah, this might be one of our
Speaker 2: top most depressing episodes because it's like everything on the
Speaker 2: planet is going to die.
Speaker 1: Yeah.
Speaker 3: I know that I'm sounding alarmist, but there's cause for alarm.
Speaker 3: This is happening, and humans are the cause of it,
Speaker 3: and it's going to cascade, I think, much more rapidly
Speaker 3: and much more powerfully than we could possibly anticipate. At
Speaker 3: the root of these extinctions is humans. But you know,
Speaker 3: I also just said that extinction is a natural process, right,
Speaker 3: and there were five massive extinction events before humans existed,
Speaker 3: So maybe we're just due for another extinction event and
Speaker 3: humans aren't to blame at all. That's wrong, flat out wrong.
Speaker 3: There's no such thing as being due for extinction. Let's
Speaker 3: look at the case of Kittred and amphibians. Climate change,
Speaker 3: human caused, habitat destruction, human cause, environmental contaminants, human caused.
Speaker 3: These have all contributed a ton, But the key role
Speaker 3: that humans have played in this particular event is transport. Yeah,
Speaker 3: Kittred itself doesn't seem to be brand new to amphibians,
Speaker 3: and I mean like we've found it in I think
Speaker 3: the earliest museum specimen is from nineteen thirty eight, and
Speaker 3: it's probably been around longer than that. But what is
Speaker 3: new are these massive global die offs. For these extinctions
Speaker 3: to happen over such a short period of time, with
Speaker 3: such widespread geographic distributions, something must have brought Kittred from
Speaker 3: point A to point B. Amphibians can't cross oceans, but
Speaker 3: humans can. For a while, while, the leading hypothesis of
Speaker 3: where Kittred came from was that during the nineteen fifties
Speaker 3: and sixties, the African Claude frogs that were being shipped
Speaker 3: around the world for pregnancy tests carried the fungus. Do
Speaker 3: you know that they were used for pregnancy tests?
Speaker 2: I you know, I didn't until we started researching this.
Speaker 2: I knew rabbits were used, I didn't know that frogs
Speaker 2: were used. Yeah, I found that very interesting.
Speaker 3: Very interesting. These frogs are one of the species that
Speaker 3: can carry the fungus without being negatively impacted, so it
Speaker 3: would have been harder to detect that there was anything
Speaker 3: going on right more recently, however, so in a paper
Speaker 3: that came from twenty eighteen, seems like the evidence is
Speaker 3: pointing towards East Asia as the point of origin of
Speaker 3: the bead fungus.
Speaker 2: I read two of the same papers as you are in.
Speaker 3: Haha.
Speaker 2: That doesn't happen very often, It doesn't.
Speaker 3: Well, I mean, we don't have a pathogen that often
Speaker 3: that is discovered in the past thirty that's true.
Speaker 2: Yeah.
Speaker 3: With this ease and speed of travel, we are basically
Speaker 3: living in a new Pangaea. That's a very serious threat
Speaker 3: to the planet species. Yeah, because species evolve in geographic isolation,
Speaker 3: and invasive species are a hugely, hugely troublesome problem Pangaea.
Speaker 2: For those whom might have forgotten their like science class
Speaker 2: from fifth grade when we learned what Pangaea was was
Speaker 2: when all of the current continents were one giant, massive
Speaker 2: super continent that was known as Pangaea. So now we're
Speaker 2: saying that it's like all of the continents are touching
Speaker 2: again because humans move things across bodies of water. Yep.
Speaker 3: Yeah, So researchers estimate that around five to fifteen percent
Speaker 3: of Earth species have been described.
Speaker 2: Wow, so there are most of the undescribed ones are
Speaker 2: like bugs.
Speaker 3: Probably probably bugs, bacteria, et cetera. Who knows, ar kia. Uh,
Speaker 3: but probably many of these will live an entire existence
Speaker 3: beforeever being described. Yeah, but why why do we care
Speaker 3: about biodiversity? Aaron? Oh, if someone were to ask you
Speaker 3: why does biodiversity matter? What would you say?
Speaker 1: Oh?
Speaker 2: Gosh, don't ask me to answer that on a podcast
Speaker 2: because I need a scripted answer and I don't have one.
Speaker 3: Well, that's that's the thing. It is hard. It's a
Speaker 3: hard question to answer because it seems so self apparent.
Speaker 3: It seems so obvious that, of course biodiversity matters. Like
Speaker 3: why why does the why matter?
Speaker 1: Right?
Speaker 3: Do you have to know why it matters? Of course
Speaker 3: it matters, But unfortunately it does matter because you we
Speaker 3: need to convince people that maintaining or improving biodiversity.
Speaker 2: Is important, is importantile and worth their money.
Speaker 3: And I'm right, that's the only way to get funding
Speaker 3: or enact the policies that will actually protect biodiversity or
Speaker 3: improve it. Basically, humans have to be convinced not to
Speaker 3: kill off other species.
Speaker 2: Isn't that sad?
Speaker 3: Yeah, it's sad. And the sad thing is that the
Speaker 3: most common line of reasoning is that you should care
Speaker 3: about biodiversity because biodiversity benefits you economically.
Speaker 2: Right, It's like, oh, that's how we find new drugs,
Speaker 2: or that's how we find new whatever, and we can
Speaker 2: make money off of that. So that's why we care
Speaker 2: about biodiversity. I hate those arguments.
Speaker 3: I hate those arguments too. Yeah, I hate them, and
Speaker 3: I understand, I understand that they are what is needed,
Speaker 3: but it's just, yeah, it's very difficult. Yeah, okay, So
Speaker 3: let me ask you a slightly different question. Okay, why
Speaker 3: should we care about amphibian species going extinct?
Speaker 2: Ooh, amphibians are good sentinels, aren't they?
Speaker 3: Actually? So I've read something that they're not, so that
Speaker 3: the image of the frog is the canary in the
Speaker 3: mind is actually not a good indicator because they are
Speaker 3: pretty resilient.
Speaker 2: That does make sense.
Speaker 3: Yeah, And also that their baseline levels aren't well established
Speaker 3: in anywhere, so it's hard to detect a change. There's
Speaker 3: often a lot of seasonality in their population densities, et cetera,
Speaker 3: et cetera.
Speaker 2: Also important parts of the ecosystem, and they do a
Speaker 2: lot of things that very.
Speaker 3: Important ecosystem services. Yes, when I was looking into this,
Speaker 3: there are four There are four reasons that were proposed
Speaker 3: as to why amphibians why do they matter? Yes, one,
Speaker 3: and I'm sure that you could find a whole number
Speaker 3: of different listicles for this kind of thing, But one
Speaker 3: is economics. So we use tons of amphibians for medical
Speaker 3: and teaching purposes and also for consumption pets ecosystem services.
Speaker 3: Like you mentioned, amphibians help cycle nutrients and they're really
Speaker 3: great prey species. They transfer energy upstream, and they're also
Speaker 3: great predators, eating tons of insects and insect eggs and
Speaker 3: arthropods and whatnot. Another reason that was proposed is esthetics. Yeah, yeah,
Speaker 3: and they've inspired thousands of years of folklore and mythology
Speaker 3: and tales. And also the final one, which is my favorite,
Speaker 3: is ethics. As humans, with our big brains and our
Speaker 3: ability to manipulate the environment, we have a responsibility not
Speaker 3: to destroy the things around us.
Speaker 2: I feel like that's a really really good argument. Actually,
Speaker 2: that's the one I'm going to use from now on,
Speaker 2: I think, because yeah, it's like, yeah, sure, you can
Speaker 2: say it doesn't matter how much we destroy the planet
Speaker 2: will keep going. But it's like, dude, are you kidding me?
Speaker 2: That's a crappy argument, like be better, be better, care
Speaker 2: a little bit, just like why is it better to
Speaker 2: rejoice in your power over things rather than respect things
Speaker 2: around you?
Speaker 3: It just yeah, fling and appreciate them, and yeah, yeah,
Speaker 3: But I think that the sad truth of all of
Speaker 3: this is that we're only going to know how important
Speaker 3: biodiversity is to humans once it's too late. There's a
Speaker 3: great quote from Paul Erlick that puts this nicely. In
Speaker 3: pushing other species to extinction, humanity is busy sawing off
Speaker 3: the limb on which it perches in the scheme of things,
Speaker 3: And I mean, like the big geologic scheme of things.
Speaker 3: Humans are nothing. Go watch the cosmic calendar from Carl
Speaker 3: Sagan's Cosmos to give you an idea of just how
Speaker 3: brief a moment in time humans have occupied, and yet
Speaker 3: we've had this enormous impact on everything around us, much
Speaker 3: reaching before humans and extending long into the future when
Speaker 3: humans are gone, and there are consequences that we are
Speaker 3: only now beginning to see and feel. By the time
Speaker 3: that Kittred was identified as the Great Amphibian Killer, it
Speaker 3: was already clear that there was no way to stop it,
Speaker 3: but at the very least an escape attempt could be made.
Speaker 3: A huge effort was started to establish amphibian populations in
Speaker 3: labs and conservation centers and freezing tissue to create this arc,
Speaker 3: preserving species while wild populations died out. But that's not
Speaker 3: a long term solution. The goal of conservation should not
Speaker 3: be to have a species exist solely in a zoo
Speaker 3: for the rest of eternity or in a freezer, but
Speaker 3: to re establish it in the wild, to restore ecosystem
Speaker 3: functionality and health. Kittred's still there and not at all
Speaker 3: bothered by the absence of its hosts. It's not safe
Speaker 3: to release these amphibians back into the environment. So what
Speaker 3: do we do now, Aaron?
Speaker 2: Oh, just that small question you want me to answer?
Speaker 1: Question?
Speaker 2: Okay? Well I might need a break first. Okay, So
Speaker 2: that was depressing. So we'll do a quick little recap,
Speaker 2: bring it back to kittred specifically, focus just on the
Speaker 2: depressing parts of amphibian decline rather than everything. Yeah, you know,
Speaker 2: small things. So, like you had mentioned, it's estimated that
Speaker 2: at least five hundred species have declined, at least in
Speaker 2: part due to Caittred. And one thing this is the
Speaker 2: paper that we both read herein that I thought was
Speaker 2: really interesting in this paper is that this puts BD
Speaker 2: kittred fungus among the most destructive invasive species of all
Speaker 2: time ever. Yeah, like more destructive than rodents, more destructive
Speaker 2: than cats, who I love but are the worst.
Speaker 3: By the way, so this is outdoor cats. Outdoor cats
Speaker 3: people who keep their cats outdoors and feral cats and
Speaker 3: so on, have caused the extinction of sixty three species.
Speaker 2: And they threaten four hundred and thirty.
Speaker 3: Yeah, so please, if you have an outdoor cat, don't
Speaker 3: have an outdoor cat.
Speaker 2: Bring your cat inside, train it to be on a
Speaker 2: leash and only let it out on a leash like
Speaker 2: mister Norris, and or build a cadio. Yeah feral cats, man.
Speaker 2: So anyways, yeah, so kittred is major. It's way more
Speaker 2: major than the other high profile wildlife pathogens, things like
Speaker 2: white nose, west nil, et cetera. Like this has affected
Speaker 2: a hugely more species, which is very depressing, and all
Speaker 2: but one it's specifically BD. So but true, No, I'm
Speaker 2: not going to do it again b D.
Speaker 3: I didn't even attempt it if you if you noticed,
Speaker 3: you know.
Speaker 2: We said it twice at the beginning. So it's fine.
Speaker 2: And one of the things that's so interesting about this
Speaker 2: pathogen is that because it's so so new, we know
Speaker 2: still so little about it. There are so many open
Speaker 2: questions that still remain. One of them is how old
Speaker 2: is this really? So, Like you mentioned, the most recent
Speaker 2: paper from twenty eighteen estimates that this fungus likely originated
Speaker 2: in Asia. So based on their data, which seems to me,
Speaker 2: even though I'm not a geneticist and I don't know
Speaker 2: how to read these papers, that well, it seems pretty comprehensive.
Speaker 2: They sampled samples of kittred fungus from every single continent
Speaker 2: where it's found, and like hundreds and hundreds of samples,
Speaker 2: and based on their studies, it seems like the Korean
Speaker 2: peninsula is likely where kittred originated, so that's where it's from,
Speaker 2: and they estimate that in the early nineteen hundreds is
Speaker 2: when it likely began spreading across the globe, and they
Speaker 2: specifically point to the pet trade out of Asia that
Speaker 2: is a driving factor in spreading this fungusah. So, one
Speaker 2: of the things that a lot of people are working
Speaker 2: on and that they pointed out really needs to happen
Speaker 2: even more is to sequence more species in Asia to
Speaker 2: really understand what the genetic diversity of kittrid is where
Speaker 2: it originated, so that we can get a better handle
Speaker 2: on how old it is and how long species in
Speaker 2: Asia might have been co evolving with this pathogen.
Speaker 3: There's that really interesting map in that twenty nineteen paper
Speaker 3: that shows continent by continent the number of like depressed
Speaker 3: populations or extinct populations or near threatened et cetera, et cetera.
Speaker 3: And you can see how much that varies across these continents,
Speaker 3: and it makes sense that there would be an East
Speaker 3: Asian origin because that is one of the lower rates
Speaker 3: of population declines.
Speaker 1: Right.
Speaker 2: Yeah, it's really interesting. But since the early twentieth century,
Speaker 2: if that's when bad began spreading.
Speaker 3: It has spread everywhere.
Speaker 2: Australia and Central America and South America seem to be
Speaker 2: overall the most hard hit in terms of population decline,
Speaker 2: but the fungus itself is found across the globe and
Speaker 2: has contributed to declines in populations across the globe as well.
Speaker 2: So there are a few major questions that are still
Speaker 2: unclear in terms of the ecology and understanding this pathogen. First,
Speaker 2: obviously is where it came from, but I just talked
Speaker 2: about that. So it's also very unclear what the impact
Speaker 2: of amphibian biodiversity and the impact of humans and human
Speaker 2: mediated environmental changes have been on caittred in amphibians and
Speaker 2: what they will continue to be on kittred abundance and distribution.
Speaker 2: We don't really know. Does amphibian biodiverse city help spread
Speaker 2: catrid and make it like a worse pathogen, or is
Speaker 2: it protective in some way like the dilution effect. It's
Speaker 2: unclear at this point. The effects of climate change, which
Speaker 2: as we talked about, is human mediated, though not the
Speaker 2: only human mediated environmental change, but a big one. The
Speaker 2: overall effects of climate change on amphibians are not great likely,
Speaker 2: but the effects of climate change and BD combined on
Speaker 2: amphibians also seems to not be great in a lot
Speaker 2: of cases. It's really complicated, and at this point we
Speaker 2: don't fully understand what the combination of climate change so
Speaker 2: increasing temperatures and more variable temperatures on top of this
Speaker 2: fungal infection are going to have on amphibian populations. But
Speaker 2: there are some studies that suggest that for some populations
Speaker 2: it's really not good and the combination of increasing temperatures
Speaker 2: and infection is actually really detrimental.
Speaker 3: So that makes bomber.
Speaker 2: Yeah, what else do we not know a lot of things?
Speaker 2: In fact, there are so many things that I just
Speaker 2: feel that I'm not going to be able to do
Speaker 2: a good job of explaining it. And on top of that,
Speaker 2: I actually don't want to end this episode on a
Speaker 2: really depressing note. And there are some aspects of research
Speaker 2: on Kittred that are really exciting and promising. So at
Speaker 2: this point I want to introduce who you heard in
Speaker 2: our first hand account, doctor Tagan McMahon from the University
Speaker 2: of Tampa, who's been studying Kittred for a number of
Speaker 2: years and from a multitude of different perspectives. She's going
Speaker 2: to tell us more about the status of kittred research,
Speaker 2: including the importance of understanding the effects that kittred has
Speaker 2: had on other species, because guess what, folks, As it
Speaker 2: turns out kittred can infect more than just amphibians. What
Speaker 2: does that blow anyone else's mind? It blew my mind.
Speaker 2: She's also going to talk about work on understanding why
Speaker 2: some populations are so detrimentally affected and other populations seem
Speaker 2: to do okay when they're infected, or seem to even
Speaker 2: clear the infection entirely, and what that means for conservation efforts,
Speaker 2: and some really exciting work on vaccine development. Just so
Speaker 2: we can end on a happy note.
Speaker 3: Take it away, Tagan.
Speaker 1: My name is Tagan McMahon, and I am a biology
Speaker 1: professor comparatipologist at the University of Tampa and I've been
Speaker 1: there for about five years now, but I've been doing
Speaker 1: amphibian decline research for about ten years. And I have
Speaker 1: been in love with amphibians, frogs and toads, especially since
Speaker 1: I was a really little kid. There's something about frogs
Speaker 1: that are just extremely charming. They're really diverse in color,
Speaker 1: They're these like little gems in the rainforests and out
Speaker 1: in New England, you'd find this bright green frog calling
Speaker 1: at the top of his lungs. I think they're just
Speaker 1: wonderful creatures.
Speaker 3: So you work with kittured fungus, and so that's obviously
Speaker 3: what this episode is going to be about. So could
Speaker 3: you tell us what kittrid is exactly and why people
Speaker 3: like you are studying it or why it's being researched.
Speaker 1: Hey, kiddrid fungus is a very weird fungus. It's so
Speaker 1: typically when people think of fungus, they might think of
Speaker 1: like Bordebella mushrooms or the type of mushroom that makes
Speaker 1: a little mushroom cats that they see in the forest
Speaker 1: growing out of a tree or out of a log,
Speaker 1: And this is sort of the same group of organisms,
Speaker 1: but it's a particular kind of fungus that lives in
Speaker 1: water and specifically is attacking frogs and living off the
Speaker 1: frog as its food resource. The fungus has probably been
Speaker 1: around for an extremely long time, but in the last
Speaker 1: few decades we've noticed that it's been causing massive declines
Speaker 1: in amphibian populations. Some populations are able to handle the
Speaker 1: infections real relatively well, while other populations are totally decimated
Speaker 1: and or are completely wiped out in a matter of weeks.
Speaker 1: So there are a handful of groups of amphibians. For example,
Speaker 1: Adylopus is a particular genus of frogs that has been
Speaker 1: completely and totally decimated by this fungus. So it's wiped
Speaker 1: out dozens and dozens of species within this group completely
Speaker 1: out of the environments. They're now being maintained in captivity.
Speaker 1: You don't find them in the wild at all. Wow.
Speaker 3: So I have a how question and a why question
Speaker 3: for you. The how question is how did it all
Speaker 3: of a sudden If you say it's been around for
Speaker 3: such a long time, what were the what was the
Speaker 3: sequence of events? Or how did it all of a
Speaker 3: sudden become more prevalent or causing these I guess pandemics also,
Speaker 3: you know almost. And then the why question is why
Speaker 3: some groups seem to be more vulnerable to kittrid than
Speaker 3: other groups? Big question?
Speaker 1: Sorry, absolutely, and unfortunately I can't give you the super
Speaker 1: concrete answer on those questions. We'll start off with the
Speaker 1: idea that it's probably been around for a really long
Speaker 1: time and yet only recently has been causing massive declines.
Speaker 1: There's there's a lot of groups that are doing research
Speaker 1: on this in a whole variety of different ways. And
Speaker 1: you have a huge conservation crisis like this, you have
Speaker 1: dozens of scientific groups that are looking at how and
Speaker 1: why questions surrounding this particular disease outbreak. What we've found
Speaker 1: is that we find kittred basically globally, anywhere you find amphibians,
Speaker 1: you find the kittured fungus. And in addition to that,
Speaker 1: people have looked through historical records and been finding these
Speaker 1: preserved amphibians with traces of kittrid fungus on them from
Speaker 1: the eighteen hundreds, and so it's been around for a
Speaker 1: lot longer than we had originally predicted when we first
Speaker 1: saw the big, massive declines and amphibians and just discover
Speaker 1: that a lot of those declines for food to the
Speaker 1: kitchen pungus. Connecting that history to what's happening today is
Speaker 1: really difficult because we weren't searching for the fungus that
Speaker 1: whole time. So we don't have a very good story
Speaker 1: as to why it's been around forever, but we but
Speaker 1: suddenly it's now freaking habits. One of the main idea
Speaker 1: is is that amphibians are sort of threatened with a
Speaker 1: whole bunch of different challenges because they're found both in
Speaker 1: the water and on land, so anything that's contaminating the
Speaker 1: water impacts them, and anything that is contaminating or destroying
Speaker 1: the land also impacts them. So the thought is that
Speaker 1: with habitat loss, with habitat fragmentation over exploitation of our population,
Speaker 1: introduction and exotic species that are eating the native species, pollution,
Speaker 1: climate change is a huge one, and other diseases all
Speaker 1: coming in that these amphibian populations, which were very strong,
Speaker 1: might have been able to handle one parasite infection coming
Speaker 1: in like catred, but now that they're dealing with pollution,
Speaker 1: climate change and the disease, their populations aren't resilient enough
Speaker 1: to be able to handle all of those threats. At
Speaker 1: the same time, there are other ideas that are out
Speaker 1: there that the strains that were around earlier in time
Speaker 1: were less virulent, meaning that they were less damaging to
Speaker 1: the host when they came through a host population, so
Speaker 1: they didn't destroy entire population sympathians, and that now we're
Speaker 1: having this really virulent strain that is moved around the world.
Speaker 1: So there's a whole bunch of theories out there as
Speaker 1: to how it's been around for a really long time.
Speaker 1: But we're only really seeing these massive declines in the
Speaker 1: last few decades, and.
Speaker 3: Some of these groups are completely wiped out and some
Speaker 3: seem to be immune. Is it is it immunity or
Speaker 3: is it something else? And does the existence of immunity
Speaker 3: suggest a longer like a history of exposure over time
Speaker 3: or anything like that historical epidemics. Maybe.
Speaker 1: Yeah, this is sort of a newer line of research
Speaker 1: in this field. As I said, you know, the conservation crisis,
Speaker 1: everybody's focused on what is happening and why, And now
Speaker 1: that we've had enough trying to answer some of those questions,
Speaker 1: we have a lot of researchers who are starting to
Speaker 1: ask some of these other they're more tangential or connected
Speaker 1: questions about immunity and things along those lines. What we're
Speaker 1: finding is that some groups are either tolerance of the
Speaker 1: fungus or resistance of the fungus. So the group is tolerant,
Speaker 1: then they can have the fungus in their skin. The
Speaker 1: fungus does just fine get nutrients from them, but it
Speaker 1: doesn't kill the host. So there are a few groups
Speaker 1: that are really well known for this one are the
Speaker 1: African flawed frogs, the Xenopus latis, for example. They're the
Speaker 1: frog that you see in pet stores all over the
Speaker 1: United States that are fully aquatic and so they swim
Speaker 1: along under the water. That particular frog totally does fine
Speaker 1: with the kitchen's fungus, so it can have a really
Speaker 1: strong infection, but it's absolutely tolerant that and it doesn't
Speaker 1: harm the frog at all. That means if that frog
Speaker 1: were to get into the wild, it would be shedding
Speaker 1: fungus out into the wild, and then the less tolerant
Speaker 1: species might be impacted by the fungus. We also have
Speaker 1: species that are resistant, meaning that if they come in
Speaker 1: contact to the fungus or come in contact with the fungus,
Speaker 1: they don't really get the infection. It's something about their system,
Speaker 1: maybe it's the bacterial fawn on the outside, or their
Speaker 1: immune system is able to identify it and get rid
Speaker 1: of it before it can establish, and those populations just
Speaker 1: don't ever really get strong infections. So again, those populations
Speaker 1: are resilient and able to move through that epidemic and
Speaker 1: not be destroyed. And there's some really cool research just
Speaker 1: starting to come out now that there are populations, many
Speaker 1: which are in Central America, that we thought were basically
Speaker 1: totally wiped out. So these are species that had really
Speaker 1: big populations. Kitchard came through, wiped them out to essentially nothing.
Speaker 1: In some case we thought they were extinct, and now
Speaker 1: we're starting to see those populations come back. But my
Speaker 1: hope is that those populations, as they come back, are
Speaker 1: going to be either resistance or tolerance of the fungus.
Speaker 1: The idea there's that everybody, all the individuals and the
Speaker 1: populations that were susceptible to the fungus were killed off.
Speaker 1: The few that could handle the infection or the few
Speaker 1: that completely resisted the infections survived, and those are the
Speaker 1: few that were there to make the next generation. See,
Speaker 1: the hope is that we're seeing some potential re establishment
Speaker 1: of populations that will be long term reestablishments.
Speaker 2: Wow, it's like antimicrobial resistant frogs.
Speaker 1: Yeah, yeah, like yeah, we could be really excited about.
Speaker 2: Yeah, that's so cool. Cool. And so you mentioned briefly
Speaker 2: too that you've worked on a number of different communities,
Speaker 2: not just in phibians. Even though frogs are maybe the
Speaker 2: most well known for getting infected with Kittrid so can
Speaker 2: you tell us a bit about what it is that
Speaker 2: you've seen in terms of the effects that this fungus
Speaker 2: has had on other communities aside from amphibians.
Speaker 1: If this is a really really exciting line of research,
Speaker 1: because for so long we have focused strictly on the
Speaker 1: kittrid tungus and amphibians, and to the extent where in
Speaker 1: a lot of the papers you'll see the kittrien fungus
Speaker 1: being called the amphibian kittrid fungus, And the reality is
Speaker 1: that it's found in other hosts, which changes how we
Speaker 1: have to handle that whole system from a management perspective.
Speaker 1: If it's only found in one house, you can focus
Speaker 1: on that one host. If it's found in several or
Speaker 1: even potentially dozens of posts that are all taxonomically different,
Speaker 1: you have to really focus your models in a much
Speaker 1: broader aspect. So the main house that I have done
Speaker 1: and work with so far are crayfish or crawfish or crawdads,
Speaker 1: and this is a group that is also found to
Speaker 1: occurring with amphibians. In many cases, crayfish will dig burrows
Speaker 1: and then it frogs will overwinter in those burrows, so
Speaker 1: they'll actually like crawl down into the crayfish hole and
Speaker 1: hang out with the crayfish in that hole over winter,
Speaker 1: and then they re emerge in the spring. So they
Speaker 1: frogs end up spending an extreme amount of time really
Speaker 1: interacting with crayfish. In addition to that, the temples of
Speaker 1: amphibians will eat the feces of crayfish and things like that.
Speaker 1: So what we found is that you have crayfish that
Speaker 1: are infected with the fungus and they actually poop out
Speaker 1: the fungus, and then the amphibians go along and eat
Speaker 1: that poop and then they become infected themselves. That changes
Speaker 1: the system and how we think about it. Right, if
Speaker 1: it's only in amphibians, then they have to worry about amphibians.
Speaker 1: If it's in crayfish, that can be a really really
Speaker 1: huge changed to our management.
Speaker 2: Does it have like a detrimental effect to the to
Speaker 2: the crawfish communities as well, or do they just seem
Speaker 2: to tolerate the infection.
Speaker 1: So we have only looked at one genus of Profiss,
Speaker 1: who's looked at a handful of different species within that.
Speaker 1: But what we found is that in the lab, about
Speaker 1: thirty five percent of individuals that were exposed to the
Speaker 1: fungus died. Wow. The ones that did not die maintain
Speaker 1: the fungus for a really long time, so like they
Speaker 1: were a viable host and a pretty strong host. And
Speaker 1: then they just kept living and living. There was no
Speaker 1: issue at all of them. Wow. So they ate and
Speaker 1: had no trouble to gain weight. They were totally healthy.
Speaker 1: So about thirty five thirty six percent die and then
Speaker 1: the rest are just fined. One of the other issues
Speaker 1: of this system is that crayfish are invasives around the world,
Speaker 1: so they have We've moved humans have moved crayfish populations
Speaker 1: all over the world. And for example, when I lived
Speaker 1: in Costa Rica, i'd go hiking. Sometimes you would see
Speaker 1: people who had put, you know, a dozen crayfish into
Speaker 1: a big plastic jug basically like a big juice jug,
Speaker 1: for example, and they'd close the juice jug and they
Speaker 1: carry it to the top of the mountain and they
Speaker 1: dump all the crayfish out in the stream at the
Speaker 1: top of the mountain, and within the next year, that
Speaker 1: entire stream would be populated with crayfish. And they did
Speaker 1: this because they're a good food resource for people, and
Speaker 1: they're really good for fishing. So people collect them and
Speaker 1: use them as bait, and so that becomes a really
Speaker 1: big issue because we're not tracking those those invasive expansions
Speaker 1: of the crayfish populations, and because the population is already invasive,
Speaker 1: nobody's generally speaking in many places, people aren't out there
Speaker 1: actively tracking how strong that population is. So we don't
Speaker 1: know if thirty five percent of the individual that were
Speaker 1: there died off because nobody's actually looking at those numbers.
Speaker 1: So it's possible declined in the crayfish populations from the fungus,
Speaker 1: but there was no one out there to ask those questions. Wow.
Speaker 3: Wow, that's fascinating. I also, I really love the image
Speaker 3: of a little crawdad and frog just for real, hold
Speaker 3: up together. Yeah, there's got to be a kid's book
Speaker 3: about this.
Speaker 1: They are really cute. They're really really cute, little little
Speaker 1: gray frogs that typically go down it and so furrows.
Speaker 2: That's very adorable.
Speaker 3: That's that's fascinating.
Speaker 2: So to try and maybe end on a slightly happier note,
Speaker 2: I saw that you've done some work on vaccine development,
Speaker 2: which is really thrilling. So can you tell us a
Speaker 2: little bit about that research and where the vaccine development
Speaker 2: might be in the in the whole process and scheme
Speaker 2: of things.
Speaker 1: Yeah, this is sort of an newer line of research
Speaker 1: for us, and I'm really excited about it, partly because
Speaker 1: when you work on a really sad topic like amphibian decline,
Speaker 1: it feels like you are helpless a lot of the time.
Speaker 1: Everything you look at is dying and declining populations left
Speaker 1: and right. And this particular line of research gives me
Speaker 1: a lot of hope that we will be able to
Speaker 1: help some populations re establish. So we're basing an off
Speaker 1: the idea of herd immunity, which you guys did an
Speaker 1: amazing job describing in your vaccine episodes. I was really
Speaker 1: excited about that. But a brief it's the idea that
Speaker 1: if we can vaccinate enough individuals in the population, then
Speaker 1: they will protect the sick and unexposed individuals from any
Speaker 1: individuals that are sick and contagious. So the first sort
Speaker 1: of bit of research we did with this, we took
Speaker 1: amphibians and we gave them the line fungus, and that fungus,
Speaker 1: as they said, brows into their skin and it takes
Speaker 1: a few weeks in many groups for the infection to
Speaker 1: ramp up. Enough to actually cause really strong damage in
Speaker 1: the froth, so we can let them have the live
Speaker 1: infection for a few days, and then we moved them
Speaker 1: over to a hot chamber and that kills the fungus
Speaker 1: but doesn't harm the froth, so it allows us to
Speaker 1: basically give them the live disease and then clear them
Speaker 1: of the disease. And so the first round of this
Speaker 1: vaccine work was giving them actual infection and clearing them
Speaker 1: and so challenge the body. Their immune systems made a
Speaker 1: nice robust response to the fungus, and so when we
Speaker 1: gave them the fungus again, they had a lower infection.
Speaker 1: So that was really cool work. It was amazing to
Speaker 1: see that they could acquire this immune response to the fungus. However,
Speaker 1: we're not going to be able to effectively do this
Speaker 1: in the while because we can't give them the fungus,
Speaker 1: clear them of it, give them the fungus clear them
Speaker 1: of it in the wild. That's just not feasible. So
Speaker 1: we developed a non infectious vaccines. So in the beginning,
Speaker 1: we were using the dead fungus. So we took it
Speaker 1: and we killed it with liquid nitrogen and then we
Speaker 1: just squirt it on the frog's back. It's the easiest
Speaker 1: vaccine to give anything, because you just have a frog
Speaker 1: and a little container and you squirt this liquid on
Speaker 1: their back and they absorb it through their skin. When
Speaker 1: we vaccinated them that way, they got just as strong
Speaker 1: a response immune system wise, and they had a lower
Speaker 1: infection when they were exposed to live hungus. So that's
Speaker 1: super exciting because that means that we can expose individuals
Speaker 1: to non infectious vaccine and then they'll have less infection
Speaker 1: when they're exposed to the actual we'll funkus. So we
Speaker 1: now have an NSF France, which is super exciting to
Speaker 1: work on all of this. So we're looking at the
Speaker 1: most effective form of the vaccine, So how can we
Speaker 1: most effectively and efficiently vaccinate individuals. We're looking at different
Speaker 1: species to make sure that we can actually vaccinate across
Speaker 1: a wide variety of different species. We're looking in the
Speaker 1: field to see how effective it is in the field,
Speaker 1: because you don't want to ever say, hey, everybody, go
Speaker 1: out and dump a bunch of dead kittrid in the pond.
Speaker 1: It's going to save everything without actually knowing that it's
Speaker 1: going to be effective and do what we expect it
Speaker 1: to do. So we're looking at the impact on other
Speaker 1: organisms in the pond and really trying to make sure
Speaker 1: we have a good idea of what's happening out in
Speaker 1: the field before we start promoting this vaccine campaign itself.
Speaker 3: That's so cool.
Speaker 1: It's really promising work, and we've had some really fantastic
Speaker 1: responses from the different species we're looking at, and so
Speaker 1: there is certainly the possibilities that we could go out
Speaker 1: and vaccinate some of these frog populations that have been
Speaker 1: removed from the environments that live in really small, isolated ponds.
Speaker 1: We could vaccinate those groups and then repopulate those ponds
Speaker 1: back to their more natural vac abundance, which would be
Speaker 1: absolutely mean.
Speaker 2: Wow, that is so cool.
Speaker 3: Oh my gosh. So I have a question that's a
Speaker 3: little bit more general, or maybe a little bit more
Speaker 3: about you. So you describe yourself as a conservation disease ecologist,
Speaker 3: which is the coolest job title. So what it really is,
Speaker 3: what kind of advice would you have for somebody. I
Speaker 3: would imagine a lot of our listeners would be very
Speaker 3: interested in pursuing a career like that, or at least
Speaker 3: learning a bit more about it. So do you have
Speaker 3: just like a brief snippet of advice on how you
Speaker 3: would go about to either learn more about that field
Speaker 3: or to become a conservation disease ecologist.
Speaker 1: Yeah, I love my job. This is if I could
Speaker 1: have described to you as a young person what kind
Speaker 1: of work I wanted to do. This is it. It's
Speaker 1: fun and exciting. It's very hard, so it keeps my
Speaker 1: brain really stimulated and it feels really meaningful because you
Speaker 1: get to see actual changes happening in the field and
Speaker 1: in the environment because of your work, which is absolutely incredible.
Speaker 1: My suggestions are the sort of too bold. From a
Speaker 1: more practical side is reach out to people who are
Speaker 1: doing research that you think is cool. You can find
Speaker 1: out what people are doing by googling scientific papers by
Speaker 1: looking at articles. If you see an article and National
Speaker 1: geographic and you think it's amazing, look for that the
Speaker 1: author that they interview and look at their research. Reach
Speaker 1: out to them. Most people doing this work want to
Speaker 1: talk to you about it, and they're really excited to
Speaker 1: share what they're doing. And if you happen to be
Speaker 1: living near those people, you can ask if you can
Speaker 1: volunteer and help. If you are in school, reach out
Speaker 1: to your faculty and find someone to do research with.
Speaker 1: It doesn't have to be the research that you wanted
Speaker 1: to do or that you want to do in the
Speaker 1: long run, just getting experience in a lab. Getting experience
Speaker 1: in the field will tell you do you like fieldwork?
Speaker 1: Do you like lab work. We'll let you know what
Speaker 1: you find exciting, what you don't find exciting, and that
Speaker 1: will help you sort of decide what's career route to go.
Speaker 2: Great great pieces of advice, Absolutely fantastic.
Speaker 3: Are there any organizations or websites or anything like that
Speaker 3: that you would like to give a shout out to
Speaker 3: in regards to Kittrid or your research?
Speaker 1: There are a lot of research organizations and a lot
Speaker 1: of conservation organizations that are doing a ton of work
Speaker 1: with amphibian decline and with tittrid fungus. One of the
Speaker 1: groups the Smithsonian Tropical Research Institute, and they're part of
Speaker 1: the Smithsonian, which has connections in the US and as
Speaker 1: well as in the Panama, does an incredible job of
Speaker 1: connecting scientists to permits and to the environment of getting
Speaker 1: them out into Panama. That's the group that I work
Speaker 1: with when I go down into Panama. They also have
Speaker 1: this huge facility of amphibians that have been pulled from
Speaker 1: the wild because the populations were in rapid decline due
Speaker 1: to the caytrid fungus, and they're maintaining these populations in
Speaker 1: captivity in hopes to be able to re release them
Speaker 1: at some point in time back to where they're supposed
Speaker 1: to be. That's an incredible amount of money and an
Speaker 1: incredible amount of time and effort put in to try
Speaker 1: to maintain this diversity, and it's something I think a
Speaker 1: lot of people don't realize it's happening. Is really I'm
Speaker 1: very hopeful that some of the vaccine work will be
Speaker 1: valuable in that space. There are other groups like Amphibian
Speaker 1: Arcs and Save the Frogs that do a lot of
Speaker 1: work as well trying to promote amphibian conservation.
Speaker 2: Excellent jinks.
Speaker 3: One last question. This might be an unfair question, but
Speaker 3: do you have a favorite frog species?
Speaker 1: Oh?
Speaker 5: Man, Yeah, so this I get asked this question a lot,
Speaker 5: and it is a really hard question because I want
Speaker 5: to tell you yes, but then I also want to
Speaker 5: list five.
Speaker 1: Or six different species. As longer I think about it,
Speaker 1: the list gets longer. And I am well known for
Speaker 1: having many favorites in my life. I think I have
Speaker 1: favorite groups that I've worked with generally speaking with all
Speaker 1: my favorites come in the tree frogs groups, but one
Speaker 1: of my very favorites is the common toad. There's a
Speaker 1: picture of me as a two year old toad, and
Speaker 1: the facialst question is me being very aware that maybe
Speaker 1: I'm not supposed to be kissing. But I figured it
Speaker 1: was back in the days of film and my mom
Speaker 1: ran inside to get this film camera. She probably wasn't
Speaker 1: very mad to me for kissing the toad. I'm gonna
Speaker 1: have to think I'm gonna go with a tom toad.
Speaker 1: But that's probably my favorite of all the groups.
Speaker 3: I love it.
Speaker 2: That's adorable.
Speaker 3: Yes, oh excellent, Aaron, Do you have anything any other question?
Speaker 2: No, this was so much fun.
Speaker 3: Oh my gosh, thank you so much for coming on
Speaker 3: and chatting with us about this. And also we have
Speaker 3: to give a big thanks to Umat for being Umat
Speaker 3: and putting us in touch in the first place.
Speaker 1: This is yeah, awesome, cool. Thank you you so much,
Speaker 1: Thank you, thanks so much much.
Speaker 3: That was great. She's amazing, She's so fantastic.
Speaker 2: It was one of the funnest we've had a lot
Speaker 2: of really fun interviews on this show. We have how
Speaker 2: thrilling for us and you listeners.
Speaker 3: I am glad that we ended it on a bit
Speaker 3: more of an upbeat note. And that's the thing is that,
Speaker 3: like it's really easy to get very bogged down and
Speaker 3: fatalistic and sort of like, well nothing matters, Yeah, every
Speaker 3: the world is going to end, etcetera, etcetera. And I
Speaker 3: get that feeling. I get it when I think about
Speaker 3: climate change, when I think about what humans have done
Speaker 3: to the earth. But I think that there's also so
Speaker 3: much to be to give us hope or at least
Speaker 3: give us some sort of optimism. You know, there are
Speaker 3: people like Tagan working on these amazing systems. There are
Speaker 3: species that are being turned around, There are people who
Speaker 3: are making an effort. And you if you want to
Speaker 3: make an effort, if you want to do something, there
Speaker 3: are many different outlets or resources for you to do that,
Speaker 3: conservation societies, volunteering, just reading more about it, it's talking
Speaker 3: to people about Kittred. It's great.
Speaker 2: If you want to learn more about Tiggin's work, you
Speaker 2: can find her lab Instagram at McMahon lab. So that's
Speaker 2: mcmaho n Underscore Lab She also curates the parasitology instagram
Speaker 2: at You of Tampa Underscore Parasitology so fun, and another
Speaker 2: one at Wandering Ecologist, which is a lot of really
Speaker 2: fun watercolors of wildlife and diseases and things like that.
Speaker 3: Yay, go check those out.
Speaker 2: Yeah, definitely. And we'll post a bunch of her recent
Speaker 2: papers on our website as well, so that you can
Speaker 2: read some of her work. And then if you live
Speaker 2: near her, bother her to go volunteer with her because
Speaker 2: she's awesome.
Speaker 1: Yeah.
Speaker 3: Other sources, sources. Yeah, So I want to shout out
Speaker 3: a couple of books I read. One is called Extinction
Speaker 3: in Our Times Global Amphibian Decline, and this was an
Speaker 3: invaluable resource. I think this is even though it was
Speaker 3: published in two thousand and nine. There's such amazing information
Speaker 3: in there on the emergence of Kittrid and also just
Speaker 3: the global amphibian crisis in general. And that's by James
Speaker 3: Collins and Martha Crump and Thomas Lovejoy. And then I
Speaker 3: also read The Sixth Extinction by Elizabeth Colbert and that
Speaker 3: was great, very very interesting book. And then a few
Speaker 3: papers quickly cretson from two thousand and two paper, Scaret
Speaker 3: two thousand at All two thousand and seven paper, Wake
Speaker 3: and Vandenberg two thousand and eight paper, Oh ham In
Speaker 3: twenty eighteen paper and Shield twenty nineteen paper. Some of
Speaker 3: those are eduls.
Speaker 2: I have several other papers as well, and we post
Speaker 2: all of these as well as links when we can
Speaker 2: on our website This podcast will Kill You dot com.
Speaker 2: Under each episode you can find the sources from this
Speaker 2: and all of our episodes, so check those out.
Speaker 3: Yes, please do. And we also have a good Reads
Speaker 3: list so you can find these books on our good
Speaker 3: Reads list. These Books will Kill You Yeah, also a
Speaker 3: link to it on our website.
Speaker 2: Well.
Speaker 3: Thank you first to Tegan for agreeing to be on
Speaker 3: the podcast and sharing her amazing brain with us. Yeah,
Speaker 3: we loved it.
Speaker 2: It was so much fun.
Speaker 3: And thank you to listeners. Thank you to you all
Speaker 3: for listening and for yeah being you.
Speaker 2: We really love doing this and you make it worth
Speaker 2: it all so much more fun than talking just to ourselves. Yeah,
Speaker 2: and thank you also to Bloodmobile for the music in
Speaker 2: this and all of our episodes. And wash your hands,
Speaker 2: you filthy animals. Wash your hands before you touch a frog.
Speaker 2: Oh that's a good one.
Speaker 3: Yeah, don't touch a frog. Don't touch a frog, don't
Speaker 3: don't pick them up, just leave them there. They're chilling.