Researchers found that gray wolves in Yellowstone National Park infected with a parasite known as Toxoplasma gondii were more likely to leave the group of wolves they were born into or become a pack leader.The study team found something startling: “A wolf that is positive for toxo is 11 times more likely to disperse than a wolf that’s negative,” said wildlife biologist Kira Cassidy, a research associate at the Yellowstone Wolf Project and co-lead author of the study.“And then becoming a pack leader was even more of an impact: A wolf that was positive was 46 times more likely to become a pack leader than a wolf that was negative.” Wolf-pack distribution and conservation Given the behavioral patterns associated with T. gondii in other animals, the researchers suspect that toxo is responsible for these trends.“We assume that there might be some sort of link between boldness caused from toxo and being more willing to leave your home range and go to another wolf’s territory and possibly be killed,” Meyer said.Christina Hansen Wheat, a behavioral ecologist at Stockholm University, said she’s excited to see further explorations from the research team."