The scariest reveals and flicks are sometimes the ones rooted in actuality — about psychopathic serial killers, late-night house invasions, and AI robotic dolls. Zombie apocalypses usually don’t rely.
However a brand new present on HBO, known as The Last of Us, presents a compelling case that maybe there’s such a factor as a practical zombie. Or realistic-ish. And it’s undoubtedly scary.
The premise of the present, which relies on the fashionable online game of the similar title, isn’t that totally different out of your typical post-apocalyptic horror story: US cities are crumbling, there are rabid people in every single place, and a manly man has to guard a younger lady as they journey throughout the nation.
The zombies, nevertheless, are really impressed. Extra particularly, they’re impressed by nature — by actual zombies that dwell on Earth.
Pedro Pascal, of The Mandalorian and Narcos, stars in HBO’s The Last of US as Joel Miller, the lead protagonist.
Liane Hentscher/HBO
In the present, which premiered final Sunday, it’s not a virus that turns folks into brainless automatons however a sort of fungus known as Cordyceps. The fungus takes over their minds and our bodies and makes them wish to unfold the fungus to the uninfected.
This fungus is actual.
In tropical, subtropical, and even temperate forests round the world, there are lots of species of fungus in the genuses Cordyceps and Ophiocordyceps (these fungi had been previously known as simply Cordyceps) that infect bugs like ants and different invertebrates. They usually do primarily flip them into zombies. The fungi take over their minds and our bodies, inflicting them to behave in such a manner as to unfold spores to others of their sort.
The fungi had been popularized in 2006 by the present Planet Earth, which captured an Ophiocordyceps parasitizing a bullet ant. And it was truly the clip under — wherein the fungus causes the ant to climb up a department, earlier than killing it and sprouting a spore-producing mushroom from the ant’s head — that impressed the sport’s creator, Neil Druckmann.
So, the fungus is actual and it may possibly flip bugs into zombies. That’s fairly rad. However does it pose a menace to us?
A comforting truth is that individuals have been consuming Cordyceps for hundreds of years now with out turning rabid. It’s a conventional Chinese language drugs, used to deal with kidney illness and different illnesses. Even wellness manufacturers at the moment are advertising and marketing it.
However to make certain — as a result of one actually can’t make sure sufficient, proper? — I reached out to Charissa de Bekker, a mycologist who researches Ophiocordyceps. A professor of biology at Utrecht College in the Netherlands, de Bekker has not seen the present however is aware of the sport. Our dialog has been edited for size and readability.
To be clear, the fungus in the present The Last of Us is actual, proper?
Sure. Cordyceps and Ophiocordyceps fungi are actual and infect bugs in the wild. There are many alternative species on the market.
Many!? How many?
Researchers have described no less than 30 Ophiocordyceps species that parasitize ants, however we all know there are lots of extra, as a result of each ant species that will get contaminated has its personal specialised Ophiocordyceps species.
There are additionally Ophiocordyceps and Cordyceps fungi that infect different bugs like wasps and flies. We additionally see this transcend bugs to arthropods like spiders. Then there’s a complete different group of fungi, in the order Entomophthorales, that does manipulation as properly — and these species don’t look something like Ophiocordyceps.
Manipulation has advanced a number of occasions throughout the fungi kingdom. The biodiversity of these fungi might be actually excessive, we simply haven’t found all of them but.
A sort of Cordyceps fungus rising on a bullet ant close to Puerto Viejo de Sarapiqui, Costa Rica.
Kevin Wells/Getty Pictures
One other sort of “zombie” fungus grows out of a lifeless winged insect in a rainforest in Vietnam.
Quang Nguyen Vinh/Getty Pictures
How do these fungi manipulate their hosts in the wild?
What we see, particularly with ants, is that they choose up spores [which are kind of like seeds for fungus] after they exit to forage for meals. The spore infects the ant and fungal cells begin rising inside its physique.
In the starting, this ant may act usually. However finally, it stops collaborating in the foraging efforts of the colony. It doesn’t talk properly with its nest-mates anymore.
After which this ant begins to turn into hyperactive and not has the similar every day rhythms of the different ants. Most carpenter ants, for instance, forage throughout the nighttime, however the contaminated ant mainly turns into energetic all the time.
A “zombie” fungus sprouts a fruiting physique (mushroom) out of an ant in Indonesia.
Reza Saputra/Getty Pictures
At one level, the contaminated ant wanders off from the colony to discover a spot in the forest to climb and chew [down on the twig or vine]. That is the place the fungus will rapidly begin to eat all the things inside, which kills the host. The fungus makes use of that power to sprout a stalk with a fruiting physique — the mushroom, if you’ll — which has spores that can fly out and infect extra ants.
By climbing greater up in the forest, the ant mainly helps the fungus unfold its spores. The particular spot it chooses to climb may very well assist with the improvement of the fungus.
This complete course of might take days or even weeks, and even months. What you typically see in zombie films, or The Last of Us, issues occur lots faster. In nature, issues take a while.
Are Ophiocordyceps truly controlling the minds of ants?
We expect this fungus is secreting sure chemical compounds that may bind to or work together with receptors or different kinds of proteins which are associated to the nervous system, and usually give rise to totally different behaviors. As an example, these may very well be receptors that usually would bind to dopamine or serotonin, which may then elicit a sure sort of habits. We’re nonetheless very a lot in the course of of making an attempt to determine that out.
We actually assume it’s extra than simply this fungus gnawing away on some mind tissue as a result of the habits is so particular.
A zombie is plastered to the wall by the Cordyceps fungus in Episode 1 of The Last of Us.
Liane Hentscher/HBO
Would you name these contaminated hosts “zombies”? Is that scientifically correct?
If you happen to evaluate it one-to-one with zombies from popular culture, it’s not fully correct. These bugs are very a lot alive, whereas in fictional films zombies are sometimes undead. These ants contaminated with Ophiocordyceps usually are not lifeless and strolling round.
What makes real-life hosts just like fictional zombies is that they’re behaving in such a manner as to profit the parasite, not the host.
Is there any cause to consider {that a} fungus like this might infect a human physique and switch us into zombies?
The very brief reply is: No.
All the things in the human physique is so totally different from the bugs that these fungi usually infect, together with our physiology, our nervous tissue, and our physique temperature. Even when the fungi had been in a position to trigger a small an infection, the equipment that’s wanted for the fungus to do such a exact manipulation is just not there.
These fungi advanced methods to control particular insect hosts over tens of millions and tens of millions of years. They’re not generalists. Every species solely is aware of the way to cope with one specific insect.
We don’t see the fungi specialists simply leaping from one ant species to a different, not to mention from an ant species to a different insect. Spreading from ant to human is simply such an enormous soar.
In the present, a fictional epidemiologist means that local weather change might make dangerous fungi extra tolerant to hotter temperatures. In consequence, they may extra readily soar to warm-blooded people. Is that an actual concern?
That’s truly an actual concern that medical mycologists have [about harmful fungi like Candida auris, not Cordyceps], although that’s not my experience.
Most fungal infections are pores and skin infections — or if, say, you’re an immunocompromised affected person, sure spores that usually are benign may settle in your lungs and trigger an issue. However most fungi don’t fortunately develop at our physique temperature. Most of them truly choose decrease temperatures.
Some experimentation reveals that fungi might, maybe, adapt to greater temperatures, as they adapt to a warming world. You’ll be able to think about that if their optimum temperature comes nearer to our physique temperature, fungal infections might turn into extra of an issue.
In the present, the fungus spreads by means of bites, not spores. That’s not how it could truly work if these fungi-infected zombies had been actual, proper?
If you happen to play the sport, you’ll see that spores do play a task in spreading an infection. However no, the fungus wouldn’t unfold by means of biting. Usually, throughout the fungal kingdom, going from one spot to a different, or from one host to a different, is finished by spores.
I’m an enormous fan of fungi. They decompose vegetation, they are often psychedelic. They’re additionally scrumptious. Is it unfair that Cordyceps are the villain in the present?
It’s nice that, lastly, fungi are hip and taking place. I hope the present sparks some curiosity in fungi on the whole, as a result of they’re extremely fascinating organisms. They’re extra vital than folks may assume.
A Cordyceps fungus grows out of a wingless insect on a leaf in Ecuador.
Luis Espin/Getty Pictures
They are very a lot the villain in the present, and that’s usually how we see parasites, as a result of they make us sick. However in nature, they’re truly tremendous vital and simply as vital as all the different organisms.
They maintain all the things in examine. If ants, as an example, weren’t pestered by sure parasites — not simply Ophiocordyceps however anything that makes them sick — then their numbers may get out of management. You may get an overpopulation of sure species. Taking out a parasite like this fungus could be like taking out a predator from the ecosystem, and that might trigger biodiversity to say no.
I’m sort of afraid to ask, however how frequent are fungi, on the whole?
To not scare you, however in each breath of air you’re taking there shall be fungal spores. Most of them usually are not dangerous to us — most spores you’re inhaling proper now are benign, or fungi that don’t know the way to cope with our physique, so you’ll by no means even discover them. However they’re in every single place.
Correction, January 26: This story, initially printed January 21, misstated when the Planet Earth documentary sequence aired; it started in 2006.
