"Yes professor, but it is a fascinating one."
"Qua-Kon Kin, our research project was specifically aimed at understanding human reproduction and you bring me here to tell me that you've discovered a parasite."
"We're still working on reproduction, our bacteriologists have discovered that, like us, Earth bacteria divide by a process of binary fission, some larger creatures also, but so far we've not managed to observe the process of division in humans. It is all very curious."
"Curious? Of course it's curious that's how we managed to secure the funding; if it wasn't curious there'd be no point in doing the research in the first place. Listen, we have only one more year of funding and I, for one, do not think that the research council will be pleased if after three years our final report says that 'its curious'. Nor will they be overly impressed if all we can stump up is another bloody tapeworm. What is it about you and tapeworms anyway?""
This isn't a tapeworm, professor, this is far bigger and its life cycle is ... well interesting."
"Oh very well Qua-Kon, tell me about your parasite then"
"Well you know the one we discovered on a previous expedition, the one that takes control of the brain of an ant, driving it up a blade of grass so that it gets eaten by a sheep?"
"The brain worm, yes I remember."
"Well we've found one that does something similar in humans."
"I wasn't aware that sheep ate humans, I thought it was the other way round."
"No I meant that it seizes control of human's brains."
"Well like many other parasites it starts of as a tiny cyst-like structure and then grows to quite some size. It uses a kind of anchor that it fixes to the abdominal cavity. And here's the clever bit, the anchor taps directly into the host’s blood supply. It steals food and oxygen straight from them."
"Clever, very clever. So it doesn't need to have any way of digesting the food itself?"
"Precisely professor, the host does all the donkey work in finding food and digesting it. The parasite just steals it. The ultimate ready meal, I suppose. Anyway it quite quickly reaches quite a size."
"Three, maybe four kilograms."
"Very. By the end the sufferer’s body is distended so much that they find it difficult to walk easily."
"And then what?"
"Well then it ... how can I put this ... leaves the hosts body. Do you remember that film our anthropology department picked up being broadcast from Earth? The one about the alien?"
"I do indeed. Another piece of offensive human propaganda, if I recall correctly, depicting anything that is from another planet as evil, crude and predatory. What of it?"
"Well professor, the parasite leaves the body in a similar way."
"Exactly, it rips itself out. A process that involves blood, gore and lots and lots of screaming. Sometimes it can take hours. Some of our scientists have had to have counselling as a result of the trauma. Compared to this, tapeworms are a walk in the park."
"But Qua-Kon we know that parasites are creatures of stealth. They operate by subverting their host's biological processes and using them to their own ends, so conspicuous a parasite would surely get killed as soon as it emerged."
"And it if were killed it would be unable to divide..."
"So if it can't reproduce how does such a parasite continue to survive? This is against every biological law. I'll never be able to publish this. I'll be a laughing stock! We'll all be a laughing stock!"
"Ah but that's the really, really clever part. It doesn't get killed."
"Well as I said earlier, it takes control of the hosts mental processes. Look you'd imagine, would you not, that if a great, blood-spattered parasite tore its way of your abdomen you'd look around for the nearest coal shovel and batter the life out it if."
"Certainly, I would."
"But they don't. They wrap it in a blanket and cuddle it.”
"Yes cuddle it professor. And they smile at it. And touch it gently. They even allow it to feed itself by apparently chewing on parts of their upper abdomen. You see what I mean when I say it subverts their mental processes?"
"This is all too much Qua-Kon."
"I've not even got my pants off yet, if you pardon the expression, professor. So great are its powers of manipulation that it continues to parasitize the host, or I should say hosts -- you know how these earthling tend to inexplicably hang around in pairs? Well it parasitizes them for years."
"Years, professor. The hosts spend many thousands of their earth pounds providing the parasite with all it needs -- food, drink, even small artifacts that the parasite seems to derive some sort of pleasure from. Although we currently have no conception of what biological purpose these artifacts play in the parasite's life cycle."
"From what you say, Qua-Kon, this sounds more like a symbiotic relationship. Mind control or not, no rational organism would surely devote so much time and effort satisfying the desires of such a parasite. There must be something that the parasite -- or symbiont as I would prefer to think of it -- gives back to the host. I simply refuse to believe that such a degree of psychological manipulation is possible."
"I know professor. The thought had occurred to us too. But our scientists report that the parasite provides nothing to the hosts. Not only that, but if the hosts aren't supplying enough food, or enough drink, or enough of these apparently functionless artifacts the parasite makes these noises."
"Noises? What kind of noises?"
"Oh horrible, blood-curdling noises. Screams the like of which you've never heard. They also throw themselves on the floor flailing their limbs so much that we initially thought it was experiencing some kind of seizure."
"And then what?"
"Oh the hosts are soon off getting food, or drink or artifacts which seems to placate the parasite temporarily. I tell you professor; some of our scientists have themselves taken to obtaining a selection of small artifacts just in case the hosts fail to stump up the goods. That's how nerve-janglingly awful the whole thing is."
"And for how many years does this last?"
"We're not exactly sure, but we get the feeling it may well last for the host's lifetime."
"A lifetime! Hell's teeth I thought that those parasitic wasps we discovered were bad, but this is immeasurably worse. How do they believe their god could permit such a thing?"
"According to our religious studies experts their god seems to actively encourage it. In some cases even banning devices that could prevent the infestation, and prohibiting surgery that could remove the parasite before it emerges."
"And humans believe that their god loves them? Tsh!"
"They are indeed a very peculiar species."