University of Montana doctoral student Connor Meyer, shown here with a wolf skull in UM’s Zoological Museum, studies the effects of a parasite on wolves in Yellowstone National Park. Credit: University of Montana photo by Tommy Martino
Key Points:
- A common feline parasite might be changing the instinctual survival behavior of wolves.
- The study of wolves and a single-celled creature nicknamed the “mind-control parasite has gone viral.
- Wolves toxo-positive are 11 times more likely to disperse from their original pack and become risk takers.
New research from a University of Montana scientist and his team has uncovered that a common parasite associated with cats might be changing the instinctual survival behavior of Yellowstone National Park wolves, who once infected are more likely to disperse across the landscape and become pack leaders.
The research paper was published in Communications Biology.
Connor Meyer, a wildlife biology doctoral student in UM’s Ungulate Ecology Lab, and his team were studying a single-celled creature named Toxoplasma gondii—often called the “mind-control parasite.” T. gondii prefers to live in felines, and infected cats spread spore-packed oocysts in their feces, which can infect all warm-blooded mammals. Once the parasite settles in muscles and brains, it’s known to boost dopamine and testosterone.
Meyer and Yellowstone park biologist Kira Cassidy started a study of the prevalence of T. gondii among park wolves in spring 2021. They discovered a toxo-positive wolf becomes more of a risk taker—11 times more likely to disperse from its original pack and 46 times more likely to become a pack leader.
Meyer and his team tested the blood from 243 wolves for toxo antibodies. They also used data from long-term and ongoing Yellowstone Wolf Project research. More than 27% of the 74 wolves they tested were infected with T. gondii.
“Eventually we found the most significant predictor of infection with wolves was when their range overlapped areas with high mountain lion density,” Meyer said. “It’s more likely wolves get toxo infection by nosing around “scrape sites,” where cougars defecate and mark their territory.”
Although Meyer believes stories about T. gondii and its supposed mind-bending powers might be a bit sensationalized, he said there is a significant need to learn more about the parasite.