Rise of the Zombie Cicadas

Billions of cicadas are due to emerge, and some of them will be infected with a truly peculiar fungus Massospora cicadina. Referred to as Flying Salt Shakers of Death, these infected cicadas have a grim and bizarre future above ground:

The fungus digests their abdomens which ruptures their exoskeletons to expose a ‘fungal plug’ designed to disperse spores like a salt shaker. All the while, the fungi are producing psychoactive compounds that may be altering the minds of their hosts. Male cicadas adopt female behavior under the influence, a clever tactic by the fungus that maximizes infection rates. And so much more.

We are joined by the brilliant mycologist and entomologist, Dr. Brian Lovett, who talks us through the mechanisms behind this insidious fungus and why it’s worth our attention.

Topics covered:

  • Periodical vs annual cicadas
  • Brood X life cycle
  • Massospora cicadina life cycle and its selected hosts
  • Active Host Transition methods in insect-eating fungi
  • Behavioral changes in infected hosts 
  • Chemical expression of the massospora fungus especially psilocybin & amphetamines
  • The significance of the 17-year cicada for researchers and why it's difficult to rear them in the lab

Show notes:

Brian Lovett’s website: https://www.lovettbr.com/
Cicada map: https://www.fs.fed.us/foresthealth/docs/CicadaBroodStaticMap.pdf
How to Eat Cicadas: https://www.bustle.com/articles/155978-how-to-eat-cicadas-that-is-if-youre-brave-enough-to-try
Cicada Mania: https://www.cicadamania.com/
Cicadas peeing: https://www.youtube.com/watch?v=QypzInWUpcI&list=PLMeYvbKcL_bJvLF0qVA-Mx8W6vZYlBumY
How to protect your trees from cicada damage: https://www.gardeningknowhow.com/plant-problems/pests/insects/cicada-damage-to-trees.htm
Cicada Shell Art: https://www.thecrafttrain.com/cidada-shell-art/
Cicada shells for biomaterials: sci-hub.se/10.1016/j.msec.2009.11.014

 

Further Reading:

Evolutionary relationship between Massospora cicadina and cicadas: https://sci-hub.se/10.1080/00275514.2020.1742033

 

 

TRANSCRIPT
Transcribed by https://otter.ai ** Subject to error
Alex 0:08
That is the sound of millions of cicadas who haven't seen the light of day for 17 years. And some of them are infected with a mind controlling by eating fungus with psychoactive chemicals.

Lera 0:31
Okay listeners, especially those of you tuning in from or near the Mid Atlantic region, are you ready for what's to come any day?

Alex 0:39
No. Billions, with a B of cicadas are due to emerge. These 17 year old cicadas known as brood x, or 10, or the Great Eastern brood have been underground since 2004. Yeah, you heard that right. There are many groups of periodical cicadas but this group, the brood x is one of the largest.

Lera 1:04
These infrequent swarms get to sit out from a lot of earthly disasters, but not when it comes to a fungal epidemic for an unlucky bunch, the rampage of brood 10 will be accompanied by a clever mind altering fungus massaspora cicadina.

Alex 1:20
So today on the show the rise of bird 10 cicadas and more curiously, what's up with that fungus that turns them into half-eaten, drugged up death machines. We spoke with my colleges, entomologist and one of our idols Dr. Brian Lovett. I'm Alex door, and I'm Lera Niemackl and this is the mushroom revival podcast.

The Broods will be the soundtrack of 2021 summer for many of our lovely listeners. emergence depends on location, but it's usually when the soil is 64 degrees Fahrenheit, so you're looking at around mid May, but it could be sooner, and in some areas concentrations can get up to 1.5 million cicadas per acre. Yeah, that's about 23 cicadas in a single square foot. Previously, these mega masses occurred in Maryland, DC and Virginia. Locals you're in for a treat?

Lera 2:34
Can you imagine being underground for 17 years?

Alex 2:37
No, I can't even fathom that. That's over half my life already. But for the broods, that's most of their lives. They only live four to six weeks above ground after they emerge. But for the near two decades that they're waiting underground, I really hope they have snacks and Netflix down there because they are chilling.

Lera 2:57
So so lazy. In fact, many cicadas will stay in the same exact spot for all 17 years. So the tree that their mother lays eggs in is usually the same tree that they attach to and feed upon about 10 weeks from the egg laying. They will hatch and dig underground just under 20 inches from the topsoil and they actually attached to the least nutritious part of the tree root called the xylem.

Alex 3:20
Is that where they feed for 17 years it takes that long to absorb enough nutrients?

Lera 3:25
Possibly, but I have no idea. It's a mystery. They're weird creatures. And you know what else is mysterious that scientists can't figure out how the cicadas are able to emerge in unison.

Brian 3:35
The general lifecycle is that a cicada after a periodical cicada after being underground for 17 years will sense that it's ready to emerge. So it will climb up to the surface, and it will wait for the soil temperature to become warm enough for all of the cicadas to emerge at once. And this synchronization allows them to avoid predators by simply filling up all those predators.

Lera 4:03
This phenomenon is known as predator satiation, since they all emerge at the same time. And since there are billions of them, their predators can't possibly eat all of them. This is advantageous to this species is they really don't have any defense mechanisms. They don't bite staying or scratch. So they're ridiculous numbers allow the population that doesn't get eaten to focus on the only real goal they have above ground to mate.

Alex 4:27
Now there's tons of predators out there, but there's a more insidious predator that lies beneath the soil. One who infiltrates the population from the inside out by drugging them whose appetite is infinite, and who actually spreads through the incessant attempts at mating. victims are slowly eat in a way until they are just bores in the wind. This is our zombie fungus, massaspora cicadina.

Brian 5:03
So while those cicadas are waiting, in this part of the soil just below the ground, they have an opportunity to come into contact with rusting spores of this specialized pathogen called mythos bra. So resting spores are a stage of this fungus this these group of fungi, which can survive a long time. So the idea is, is that the rusting spores from the previous generation 17 years ago are deposited in that soil and they wait patiently for 17 years until a cicada climbs up to that burrow. Once the fungus comes into contact with cicada burrows into this Qaeda and initiates infection. During this time, the cicada will emerge from the ground, it will transform into an adult. And then the adult will have about a week where it just acts and looks like a normal adult cicada. So this process of infection is sort of latent initially, but over that time, the fungus is growing inside of the abdomen of the cicada. So you can imagine a male cicada, the way that they call their abdomen is hollow. And this fungus is just filling that space, essentially muffling that call until it has filled the entire abdomen of that cicada and it continues to grow. And what happens is you see very dramatically in rings, the abdomen of the cicada will slough off revealing this fungal mass. So instead of having this dark, segmented abdomen, you have this chalky, white and yellow plug on the back of that cicada. So at this stage, we don't really have a cicada anymore. We have a fungus transmission machine.

Lera 6:48
A Fungus Transmission Machine. That sounds ominous. But sometimes I feel like a fungus transmission machine. I mean is that now what we're doing with this podcast using machines to transmit fungal data? Are we all infected?

Alex 7:00
Same mission, separate methodology. I'm like master spore, we aren't creeping into your body through your hair follicles penetrating the cuticle eating everything we can until you're just head with skin obeying the chemical signals to adopt drugs and few sex parties that lead to your inevitable demise.

Brian 7:19
And this stage is a specific kind of house manipulation which we call active host transmission, which is where the fungus is manipulating its host to transmit the pathogen. So essentially, the fungus is now in charge. And because the abdomen of the cicada has fallen off, it can't reproduce, which is its only purpose above ground. So the purpose of this cicada has been wrenched from it and it has been replaced with transmit fungal spores. So this the Qaeda is harboring these immediately infective spores that we call kinnitty up and these Kenedy are going to be rubbed off on surfaces. When the cicada flies, it's going to be spraying these spores on any individuals that are around it. And when males cicadas are infected with this fungus, they're manipulated by the fungus to behave like female cicadas, which will entice other male cicadas into attempting to mate with them, which instead of resulting in more cicadas results in that male becoming infected because it mates with the infective Canadian plug. So this stage of infection, this first stage of the Canadian stage is a period of amplification for the fungus. It's infecting lots and lots of other cicadas because it has enlisted the infected cicada which is still living, to help transmit spores and even trick other cicadas into becoming infected. So that process carries out throughout the the middle of the cicada season, and any cicadas that get infected with that kinetico plug will develop into rusting spore infections, and those cicadas will die and they fall to the ground. And those spores will wait for the next generation of cicadas to infect.

Alex 9:08
We may be fungal transmission machines, but we definitely aren't flying salt shakers of death.

Lera 9:15
Which by the way, is the proper nomenclature that Mr. Brian Lovett and Dr. McKesson use in their lab. Funny as it is the salt shaker of death is actually an accurate analogy, like a salt shaker. If it falls over salt grains will spill out and with an infected cicada, picture those grains of salt as spores being dispersed in abundance wherever the cicada moves, but that's not their primary way of spreading their spores. No, no, the fungus is much more clever than that. infected cicadas will actually carry on with their cicada duties but with even more extreme efforts to mate body to body contact is after all it contagions most productive form of transmission. So infected females will continue to flick their wings to attract males, but infected males will something more intriguing is going on here. The males will forego their natural behavior of singing to find mates and will actually mimic the female behavior of wink flicking to attract other males. Can you imagine being the cicada that falls for these false mating calls?

Alex 10:16
It's 10pm. Do you know where your children are? Just say no to zombie fungus drugs.

And I've also heard about some notable molecules that the fungi secretes into this cicada, notably amphetamines and psilocybin have we done research on that cocktail on what is doing and how much?

Brian 10:40
So the research that's been done on was done in the in the cath lab before I joined, and mostly it was simply characterizing that those compounds are there. So the way that you can do this is by looking broadly at any compounds that are present in a sample. And then when you identify, essentially through the mass of those compounds, what compound you think you might have found in your sample, then you can go and get a standard, which is for sure that compound and you can run them together to see if they are if they match. So using those sorts of approaches, they found that the periodical cicadas that are infected with the SOS bra contain cathinones, which is an amphetamine, an annual cicadas, which are infected with a with a different group of muscles bra contains psilocybin. So this is really interesting, because we know for certain that the fungus is manipulating the behavior of this kiddos. And we know that these are compounds that would manipulate the behavior of people. We even had have had discussions with colleagues about like the kinds of manipulation, the kinds of behavioral changes that people might have, and their judgment and the risk that they might take when they're when they're on these compounds. And it's not hard to to make a leap to say these compounds are having an effect on on the cicada. But that work has not not been done yet. So I don't really want to speculate too much on specifically what they're doing. But we do know that when they're infected with these fungi, these compounds are present. And we suspect that they're probably manipulating the cicada to be better at transmitting the fungus. So one really obvious example is that these cicadas these periodical cicadas have lost half, ostensibly half their body, and they're walking around like normal, and are like enticing other cicadas to mate with them. So even just acting normal, when half of your body is missing, is a huge manipulation. So the idea that maybe these fungi are producing compounds, which will sort of soothe or maintain the activity of the cicadas could be really important for the funguses Fitness. So So those compounds, could could be involved in the manipulation of the cicadas. But we're going to want to do more work on how the fungus is synthesizing these compounds, I'm sure that you too, will know that this group of fungi is not where psilocybin is normally found. And also cathinones is known from the cat plant, not from fungi. So understanding how these fungi learned to make these compounds, and also conducting behavioral tests and cicadas where we dose them with these drugs and see how their behavior changes are things which would be required to really fully understand what's going on there. And there are challenges to to both of those endeavors. But I think that's where the where the research and these fungi is headed.

Alex 13:35
So just so I'm clear, the brood x that comes out every 17 years or so that has the cathinones in it, correct? Yep. And it does not have any psilocybin. No, and then the annuals have psilocybin. So how Has anyone done any research on how many infected cicadas they would have to eat, to have a dose of psilocybin near how many milligrams of psilocybin are in each cicada?

Brian 14:04
So, as you can imagine, this is not an uncommon question. The cicada is very large for an insect. That's one of the things that makes it so exciting and means that when these birds come out, they make the news there, they're, you know, an inch or two long, these cicadas but even still, right, you're talking about like the size of a long finger. They're very, very small compared to us. So the amount of these compounds to manipulate the cicada are just so tiny, that they're not really operating on the same scale that you would need ingesting them. And that's, that's further ruined by the fact that these are not the only compounds which are being created by these fungi. So I would say that if you were to just get a bowl of mythos bra infected individuals and just start eating, that you would experience effects really horrible effects from the other compounds these fungi are producing to facilitate their lifecycle, then before you would feel effects from any of these, any of these drugs, I'm so curious on what the other compounds are, I mean, psilocybin make, they both make sense, right? The amphetamine, it's, you know, your cranked up your I could see someone amped up on amphetamines losing half their body and not caring. Yep. And still Simon also with just ego death and not identifying with their body and just transcending the body, you know, totally at the same time this type of manipulation. I mean, what is a zombie if not ego, Duff? So yeah, it's not it's not unreasonable to think of it that way, but characterizing the metabolic profile. And then also, the other challenge with looking at what metabolites fungi are producing is figuring out what genes are responsible for the production of those metabolites. That process is very complex. And we're only just scratching the surface for these fungi. And we have to go and collect them from broods that are emerging to be able to continue these studies, because you can't have a cicada population that you're wearing in the lab because they need tree roots. They need grassroots they need soil that they can wait in for 17 years and all those things are really hard to artificially provide.

Alex 16:27
We are still at the very tip of our understanding of this wild and crazy phenomenon, with or without the massage bra infections. folks in Delaware, Illinois, Georgia, Indiana, New York, Kentucky, Maryland, North Carolina, New Jersey, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, Michigan, as well as Washington DC. It's going to be a cicada Wonderland. If you find any of these infected cicadas, tag us on it.

Lera 17:01
What else can you do with these cicadas? You ask? Well, be sure to check our show notes for some inspiration. You can eat them, turn them into arts and crafts prank your friends harvest the cotton from their exoskeletons for biomaterials. The Brood are your oyster.

Special thanks to Brian love it stay tuned for more epic stories from him on the mushroom revival podcast. This researcher is a prime example of the many humble scientists working behind the scenes on some seriously badass myco logical projects.

Alex 17:35
If you want to support the show, and keep content like this coming can do so by visiting our website mushroom revival.com and purchasing any of our functional mushroom products. Whether you want to support your energy, your focus a sense of calm to support your immune system or your body's natural ability to deal with occasional stress. Mushrooms are your friends, podcast listeners get a special discount for 10% off. Other ways you can support is leaving a great review and telling your friends and family all about the wonders of fungi. And as always, much love and may the spores be with you. Unless you're a cicada.

Lera 18:26
Then you might just want to stay home.