GamesBeat Science Behind The Game: The Last of Us September 27, 2013 11:32 AM Derek Nichols This post has not been edited by the GamesBeat staff. Opinions by GamesBeat community writers do not necessarily reflect those of the staff. It’s been quite a while since I’ve unloaded a new “History” feature upon you guys and up until now, they’ve focused squarely on the Assassin’s Creed franchise. If you want a refresher, have a look at my previous entries. With the summer drought in full effect, what better time for a reboot of this series? With a reboot also comes change and as such, I’m leaving the Assassin’s Creed franchise behind for now. Who knows, with the pirate-centric Black Flag hitting later this year, a new opportunity may be there. For now, lets take a look at Naughty Dog’s new survival IP, The Last of Us with a new focus on SCIENCE. With a fungal outbreak claiming a large chunk of the world population and humanity struggling to survive, is this even a possible scenario? Just what is the deal with the Cordyceps fungus? Let’s dive deep into the science behind the game, shall we? *Side Note* There are a couple of early game spoilers below which I have marked. Other than that, what’s below is centered more around actual science so don’t fear about having the game spoiled for you or anything. Q: So the Cordyceps Fungus is a real thing? A: Yes indeed, it’s not a fictional fungus made for games at all. We’ll be taking a look at the Ophiocordyceps family of fungus, specifically the ophiocordyceps unilateralis being featured heavily in The Last of Us. This fungus is also something which you may have seen from the BBC Documentary, Planet Earth. There’s actually quite a lot of cordyceps species within this genus of fungi to my surprise with the majority of them targeting a different insect such as ants, butterflies and moths. This fungus is particularly active in places like Asia, Africa, and South America taking root in jungles. Q: What does the game’s fiction say about this fungal outbreak? A: While never confronting the topic head on in a cutscene, the player can glean details from the environment such as newspapers. For example, if you go back to Joel and Sarah’s house, there’s a newspaper stating that the outbreak seems to have stemmed from infected crops. Ultimately, it’s never fully explained how this outbreak occurred but it’s implied that the fungus mutated in some way in order to effect humans. (SPOILER) This mutation can also be seen with Ellie as she carries the infection but seems to be immune from it’s effects on her brain. (END SPOILER) Q: Alright so how does this thing work? A: Spores. That’s the key item here. Once the host has been infected by spores, the fungus will enter the body through the endoskeleton via enzymatic activity. As the fungus spreads, it begins eating non-vital soft tissues (can’t kill the creature yet) and producing compounds which change the behavior and brain patterns of the creature. In addition, the fungus also begins fortifying the exoskeleton to protect the host from dangers, more for the sake of the fungus than the victim. At this point convulsions begin, knocking the creature from whatever it may be on to the ground. As the fungus exerts it’s control over the ant who’s now in a zombie like state being controlled against its will, the fungus goes about looking for the perfect place to fully grow. The reason for this is that the Cordyceps need a specific temperature and humidity to “bloom”, so they take control and use these unwilling insects to accomplish that goal. Once in bloom, the fungus repeats this process by releasing spores into the wind. What’s interesting is that over time, ants have developed the ability to sense the infected and will carry them to a remote place away from the colony to prevent any sort of event which would take down the entire colony. It’s a primitive but every effective form of quarantine. Very smart if you ask me. Q: Are there really different stages (runners, clickers, bloaters, etc)? A: Not on such an extreme level as the game but to a lesser degree, yes, there does seem to be various phases that the infected host goes through. Like runners, infected insects will begin to convulse and start to lose control as the fungus spreads to the brain. This will also cause them to change their behavior and how they act eventually losing control of their body to the fungus completely. As the ant climbs up the stem of it’s plant, effectively a death march at this point, and it clamps onto the underside of a leaf, the fungus kills the ant and begins growing outside of it’s head. This would mirror more of the clicker/bloater stage with the only difference being that the ant is dead by this point. Q: So is the situation presented in The Last of Us possible? Can humans be affected? A: While it’s certainly a terrifying prospect, it does not appear to be the case as this fungus targets insects. Oddly enough, certain strains of the fungus (Ophiocordyceps sinensis) are even used in traditional Asian medicine in locations like Tibet and China. After playing The Last of Us, that seems like a horrible idea, right? According to them, it’s great as an aphrodisiac and is also used to treat ailments from fatigue to cancer. Far as I know, no runners or clickers have been reported out there so I’d say we’re safe from harm. Want to see more History/Science behind the game articles? Let me know in the comments! What would you like seeing?