There are dog people and there are cat people. Just a preference, right? Wrong. There is evidence to suggest that cat lovers don’t really love their cats as much as they think they do, that in fact they’re being controlled by a horrific parasite that needs cats to survive…
Today I’m talking about monsters. In the past, I’ve talked about cryptozoological monsters, those creatures that are the stuff of legend, myth and rumour. The Loch Ness Monster, Bigfoot, Trunko, the Montauk Monster…
The funny thing is, the scariest monsters are the ones that actually exist.
Enter Toxoplasma gondii, probably the most famous and most controversial neurological parasite. When you think about it, all parasites are pretty monstrous. The fact that their entire lifecycle depends on slowly sucking the life out of other creatures—their hosts—is both nightmarish and one of evolution’s curiosities. This microscopic protozoan basically looks like a blob, but don’t let that fool you. T. gondii has some rather frightening abilities.
It starts its life in cat faeces, where its eggs lie in wait to be picked up by carriers like rats. Once the eggs are safe and warm in the guts of their temporary rodent hosts, the next stage of T. gondii’s lifecycle begins. The eggs transform into tachyzoites, which then migrate to the rats’ muscles, eyes and brains.
But T. gondii needs to reproduce. And strangely there is only one animal in which the parasite is able to undergo sexual reproduction. Cats. In order to lay more eggs, the tachyzoites need to find their way into the bodies of our unassuming pets.
The problem is, rats aren’t totally stupid. They’ll tend to shy away from areas where cats live, because they know they’ll get chased and killed and eaten. When they do come across cats, they’re generally quite good at escaping them.
So what is T. gondii to do? It’ll have to resort to some mind control, of course.
What happens next is pretty creepy. The tachyzoites inside infected rats will alter their behaviour and cause them to start hanging around cat-populated areas. Then they’ll cause the rats to become sexually aroused by the smell of cats and leap fearlessly into their claws and die, releasing the tachyzoites back into the cats for the cycle to begin anew. It’s a bit like the terrifying Cordyceps, a parasitic fungus that will cause an infected ant to climb to the top of a plant, where the temperature and humidity are at optimal levels, before bursting out of its head.
The problem with T. gondii is that rats aren’t the only animals capable of being the temporary hosts for the second stage of its lifecycle. The little parasite is also rather partial to… us. In fact, some researchers have estimated that more two billion people on Earth are carrying T. gondii tachyzoites around in their brains as we speak.
And if these parasites are causing rats to commit suicide, what might they be doing to humans?
Well, folks, it ain’t good news. Studies have shown a statistically significant correlation between T. gondii infection and schizophrenia, traffic accidents, and sex-specific changes in personality. For instance, infected men are more introverted, suspicious, inclined to disregard rules, and oblivious to people’s opinions of them. And infected women are—bizarrely—the opposite: more outgoing, trusting, rule-abiding and image-conscious. In addition, infected hosts have slower reaction times and are more likely to take risks, which is why they’re more likely to get into car accidents.
Worse, there is a significant correlation between T. gondii and suicide rates, particularly in women over the age of 60.
So, as it happens, this tiny parasite is causing us to commit suicide.
What’s also interesting is that schizophrenia hasn’t always been as prevalent as it is now. Cases of schizophrenia rose sharply in the latter half of the 18th century. Can you guess why that was? Because for the first time people started keeping cats as pets.
It really does beg the question—are cat owners really in control of their own minds? Admittedly, I’m a dog person, and I can see why people love dogs. Scientists have discovered that many people love their dogs as much as their children—and the feeling is mutual. Cats on the other hand are distant, cold, self-important creatures that aren’t known for being affectionate to their owners unless they want something. So why do millions of people love them?
Well, perhaps they don’t. Perhaps they keep their feline friends around because T. gondii is telling them to. Alright, so blaming the nation’s love of cats solely on parasitic mind control could be a stretch, but the evidence does show that T. Gondii is affecting the way we think and behave.
The fact is T. gondii is just one of an untold number of parasites capable of burrowing into human brains and tinkering with our minds. Studies have shown that the flu virus boosts our desire to socialise so that it can spread. In addition, many people at the end stages of AIDS and syphilis experience an intense craving for sex.
Joanne Webster, a parasitology researcher at Imperial College, London, says this:
“The brain is a ‘privileged site’ for many parasites. And that really challenges the concept of free will — after all, is it us or our parasites who ‘decide’ our behaviour?”
Try not to have nightmares tonight.
Next week: a review of conspiracy thriller The King’s Deception by Steve Berry