Mind Control Parasites Are Changing Wolves More Than We Realized

A gray wolf pack leader infected with a mind-control parasite — that may sound like the plot of a sci-fi film, but according to CNN, it's not that uncommon. Also based on a 2022 study published in Communications Biology, that parasitic infection may have not only influenced the wolf to become a leader, it also might also have caused the animal to engage in other risky, sometimes life-threatening, behaviors. Most fascinating of all, the mind-control parasite in question can be found in your kitty litter box, and we as humans may also be susceptible to similar mind-altering effects. You may, in fact, already have some of this mind-control parasite living inside you.

These conclusions, published in the study "Parasitic infection increases risk-taking in a social, intermediate host carnivore," were reached by observing wolf packs at Yellowstone National Park. The species was reintroduced to Yellowstone in the mid-1990s. What researchers found is that wolves infected with a parasite called T. gondii were 11 times more likely to leave their pack to strike out on their own, and 46 times more likely to become a pack leader. These behaviors carry benefits for individual animals and for the wolf species. What was also revealed in the study was that aggressive or antisocial behaviors in wolves were also linked to infection, and the wolves may not have left on their own — they may have been expelled.

According to Live Science, T. gondii, the parasite linked to behavior changes observed in Yellowstone wolf populations through a type of infection called toxoplasmosis, lives in all sorts of mammals, but most commonly cats, where due to a fluke of nature, the parasite can complete its life cycle inside a single host. Cat owners may recognize toxoplasmosis and T. gondii, often transmitted through cat feces, as a risk of cat ownership, particularly for pregnant women. According to the Mayo Clinic, T. gondii can be transferred from mother to fetus during pregnancy, and infection can also come as a result of undercooked meat consumption. Some estimate T. gondii lives in nearly a third of all humans, and as much as 10% of the U.S. population.

As mentioned, a fascinating evolutionary byproduct of the cat-T. gondii relationship is that the parasite can live its whole life inside a cat. So much so, that when inside other mammals, evidence suggests T. gondii will change that creature's behavior to find its way back inside sweet little Mittens. For example, for reasons not well understood, certain infected rodents seem less afraid of feline predators, which contributes to them getting eaten. As a result, T. gondii returns to its favored, forever home, as CNN reports. Signs point to T. gondii increasing risk-taking behaviors, anger management issues, and even possibly certain types of mental health challenges in humans. For Yellowstone wolves, toxoplasmosis caused by T. gondii could cause similar behavior changes.

Crucially, though, as the "Parasitic infection" study published on Communications Biology goes on to point out, so-called "toxo" infection may influence certain wolves to claim their own territory, form their own pack, and establish a new breeding population, which benefits the gray wolf species in Yellowstone and elsewhere. But infection may also cause certain animals to behave more aggressively — remember the signs of anger management issues linked with toxo infection in humans. In other words, some wolves may not leave on their own, they might get kicked out because of antisocial behavior.

What's more, living all alone for a wolf carries risk. In a best-case scenario, the individual animal successfully builds a new pack, but life as a lone wolf may get the creature killed. Also of note, Yellowstone wolves live in close proximity with cougars, which are the likely cause of infection. The prevalence of toxoplasmosis infection in Yellowstone gray wolf populations was established through blood tests, according to CNN. More research is needed to firmly establish a link between toxoplasmosis and behavior in mammals, but what's for certain, the results of the study will cause some to think twice when they see "leadership qualities" listed on a job candidate's resume.