Hacker News new | ask | show | jobs
A fungus that infects cicadas and pushes their mating into hyperdrive (npr.org)
57 points by cwan 1862 days ago
8 comments

Reminds me of this NatGeo Hostile Planet video on Cordyceps, a fungi that infects ants [0] It drugs the ant, takes control of its muscles, and forces it to climb up to a spot where there's just enough sunlight and humidity for the fungi to grow some more. 3 weeks in, the ant is all but a breeding ground of Cordyceps ready to unleash on other ants, with enough reach to wipe out entire ant colonies.

Here's the kicker, there are over 600 species of Cordyceps that infect a variety of insects.

May be the fiction writers have it wrong... It could very well be a Fungus that likely causes a zombie apocalypse, having evolved from lack of rain forests and crawlers to infest...

[0] https://www.youtube-nocookie.com/embed/vijGdWn5-h8

Indeed, this is the central plot point driving the narrative in The Last of Us. [0]

https://thelastofus.fandom.com/wiki/Cordyceps_Brain_Infectio...

They grow in animals, insects, with 'open' circulatory systems. Something that large growing in our 'closed' circulatory system (blood vessels/tubes) would quickly kill us.

https://en.wikipedia.org/wiki/Circulatory_system#Open_circul...

> It drugs the ant, takes control of its muscles, and forces it to climb

Really? Is the climbing caused by muscular movements provoked by the fungus, or is it caused by the fungus causing the ant to desire to climb up to such a spot, and letting the ant move its own muscles?

> It could very well be a Fungus that likely causes a zombie apocalypse

This is the plot of The Last of Us.

The real question is “how many types of parasites ALREADY modify human behavior”.

We know toxoplasmosis does it, but how many have we not yet detected?

With toxoplasmosis in particular, people cite that old study over and over. I always wonder to what degree that's been replicated, or to what degree the study's claims have been exaggerated because of their controversial nature.

Please bear in mind, I have no particular expertise about this issue, and so it's possible that my doubts here are not well founded.

This paper, right?

https://academic.oup.com/schizophreniabulletin/article/33/3/...

The only valid conclusion here is that further study is needed.

We know our gut biome in general has a huge effect on our behavior as well (most obviously around food choices), though I don't think those are technically "parasites".

Less interesting but still worth noting, many infections cause us to sneeze and cough in ways that increase the spread of the infection to others. Ain't evolution grand.

Another one, I remember that late stage Syphilis in at least some cases causes sexual promiscuity.

I've also read that the cold or flu virus makes us seek more human contact and feel more affectionate, supposedly overriding our mind in order to propagate the virus.
That explains a lot of bad decisions with the Corona Virus
I'm keenly aware that I know next to nothing about biology, but I was wondering about something:

If I understand this article correctly, the cicadas that were infected during the last cycle can't impregnate or get impregnated (because, as the article puts it, their butts fall off). However, they can and do infect other cicadas. Shouldn't this this result in every cicada that can get infected getting infected eventually, at which point the population dies off after the next cycle produces no baby cicadas?

If so, is the ideas that this is a new fungus, or new behavior, not something that's been around and been at some kind of equilibrium for 1000 years or something?

"In yearly cicadas, the fungus makes them instead become hypersexual from psilocybin — the same chemical found in psychedelic mushrooms."

I don't understand what's being said here. The fungus causes them to eat magic mushrooms?

Edit: This is a better article: https://www.theatlantic.com/science/archive/2018/07/massospo...

Mushrooms are just the fruiting body. Fungal cells don't differentiate, so odds are good that if the mushroom gets you high, eating the dirt under the mushroom - where most of the fungus is - will also do the same thing.

If you were somehow infected by one of these mushrooms, you'd be tripping all the time, not unlike the people who have beer yeast in their GI tract are slightly inebriated every time they eat simple sugars.

Injecting spores into your blood stream can infect your body with mushrooms. DO NOT DO THIS, it can be fatal.

https://www.insider.com/man-injected-with-mushrooms-grew-in-...

Wait. If he boiled the mushrooms, how did get spores? Does that mean Agaricales spores can survive 100ºC? Yikes.
Looks like he had bipolar disorder. Manic episodes can produce imprudent behavior such as this.
That makes so much sense now. Thank you kindly for clarifying.
Psilocybin is the active ingredient (a psychedelic prodrug, or drug precursor that's metabolized into a drug) in Magic Mushrooms. The fungus generates psilocybin and sheds it into the cicada, causing them to become hypersexual.
I did not realize just how many different kind of mushrooms produce that chemical. All over order Agaricales.

https://en.wikipedia.org/wiki/Psilocybin_mushroom

So what's weird is that Massopora isn't even in the same division as Agaricales. They're both fungi. So what does that mean? That the classification is wrong, convergeant evolution, or fungi have been making drugs for an insanely long time?

I wonder how the fungus knew how to make psilocybin, and that psilocybin was the right thing to make? Nature is pretty intense.
Presumably this is an outcome of selective breeding. The symbiotic interaction results in more offspring for both species. The invisible hand of mother gaia "knows".
But the cicadas have no genitalia at that point.
I don't totally follow your confusion - it's "the same chemical found in magic mushrooms". It's not implying they consume magic mushrooms.
This reminds me of the film that kicked off David Cronenberg's career (and also one of the first films in the body horror genre): Shivers

https://en.wikipedia.org/wiki/Shivers_(film)

The Screwfly Solution (https://en.wikipedia.org/wiki/The_Screwfly_Solution) comes to mind, great story by Alice Sheldon.
> The fungus takes over their bodies, causing them to lose their lower abdomen and genitals. And it pushes their mating into hyperdrive.

Unclear. How do they mate, or even attempt to mate, without genitals?

"It's a failed mating attempt, of course, because there's no genitalia back there."
Yes I read this but it still needs some explanation. I can maybe understand that the infected insect still wants to mate even without genitalia, but why do the sane ones fall for it?

I guess I need to learn more about cicada mating habits.

Well, remember, what you are dealing with are basically very small robots with limited programming and a few specialized sensors. "Oh, it is flicking its wings at a certain rate; it must be a female waiting to mate."

And so you have a subroutine where you target the basic shape, go in for a landing, clamp on, and start prodding about with your nethers. They're like state machines in many ways.

Consider that you can put a single chemical on a live ant that makes other ants think that it is dead. They pick it up and take it to the graveyard. Now it can thrash around and wiggle during this but -- nah, smells dead, is dead. Therefore, pick up and carry to designated graveyard location.

Consent to mate is in fact fairly distinctive to human beings. It's certainly not a concept which applies to insects such as cicadas, which just jump on each other and do the business.
Other mating models:

- Millipedes generally work on a model where males leave packets of sperm on the ground and females find them and pick them up. Mating does not take place.

- Fish may just release sperm / unfertilized eggs into the ocean and hope they find each other.

- Some mayflies have just four legs, the first pair having developed into "arms" whose only use is restraining a struggling female.

- Male anglerfish drift around until they find a (much larger) female, at which point they burrow into her skin, attach permanently, and live as a parasite that occasionally releases sperm.

Cicadas may not worry about consent, but insects and other crawly things in general do, as you can tell by the fact that they put on mating displays.

Bedbugs are a particularly interesting species, in that they practice traumatic insemination[0]. The male, in order to overcome female resistance, rips through her abdomen to deposit his sperm. Large, confined bedbug colonies often go extinct for this reason: all the females end up dead from repeated traumatic insemination.

[0] https://en.wikipedia.org/wiki/Traumatic_insemination

Yep. Bedbugs are one of those species where I would have no objection at all to gene-driving them into oblivion.
> Consent to mate is in fact fairly distinctive to human beings.

What? https://en.wikipedia.org/wiki/Courtship_display

Sure, I said fairly distinctive rather than unique.

It's interesting that monogamy and mostly-consensual sex are mostly found in some birds (not you ducks), rather than our closest relatives. There are a lot of mammalian paradigms for sex, for placental mammals in our weight class there's rather a lot of intramale competition, and estrus; the female being willing to be mounted by whatever male happens to win the fight is pretty much orthogonal to consent as we humans understand it.

It seems like a pedantic objection given that both the parent and myself were talking about insects, where the concept makes very little sense.

"[The fungus] is sexually transmissible," Kasson tells NPR. "It's a failed mating attempt, of course, because there's no genitalia back there."
Maybe only the fungus mates
And this is why I don't do shrooms.
Right. Eating shrooms might fix your brain, and enslave you to think about forests and shrooms with some affection for the rest of your life. It is a tragic outcome for those who prefer to be isolated from nature.
My brain is just fine, thank you for looking out though.
Sometimes I feel like we are sharing the world with fungus. As in, fungus consciously doesn't generate spores on us because it figured out that we will just grow it and put it in drinks and spread it any way. So using our mental processing power just let fungus realize it didn't have to try to use all its energy on the host capture and spore release routine.

And of course, the observation that it has nothing to do with us humans.

What we consider lower forms of life have been around a lot longer than us. Fungus predate plants and originally ate minerals. They created the soil for plants to even evolve. Plants evolved in an environment created and controlled by fungus. Many plants have a symbiotic relationship with fungus. Entire ecosystems are connected and communicate by a mycorrhizal network. We owe our entire existence to fungus.
Not only that, but our own cells are similar to fungal cells, which is one reason that it's so difficult to create antifungal medication that isn't also toxic to humans.
Up until the green revolution, all land agriculture on earth was mediated by fungi. Lichen are basically fungi farming cyanobacteria, and some people suspect there's an unbroken chain all the way down the plant evolutionary tree. It's not outside of the realm of possibility that trees are just a very long breeding program by fungi as well.

We, as cousins to fungi, get to enjoy the literal and figurative fruits of their labor.

Some podcast -- RadioLab I think -- did an episode on how climate change (specifically, warming) has been putting selective pressure on fungi to make them hardier towards infecting warm-blooded animals... at the very same time that the average human body temperature has been trending down.

Not a good thing.

It was RadioLab and it was probably the scariest thing I’ve heard about global warming yet.
By any chance do you know the name of the episode or the episode number? Thanks!
bacteria instead of fungus, but similar premise:

https://whatever.scalzi.com/2010/10/02/when-the-yogurt-took-...

bizarre and brilliant!
Have you ever had athlete's foot or jock itch?
From what we can tell they don’t take us over and obviously change our behavior. Someone has to tell us they are on psychadelic mushrooms or took a cordyceps energy drink.

Skin infections occur.