What makes a wolf leader of the pack? New research says it's parasites in the brain A new study finds that wolves are much more likely to be pack leaders if they have been infected with the parasite Toxoplasma gondii.

What makes a wolf leader of the pack? New research says it's parasites in the brain

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What makes a good leader? Assertiveness? Empathy? What about - and stick with me here - parasites in the brain? A new study published in the journal Communications Biology indicates that the presence of the parasite Toxoplasma gondii in an individual wolf makes it much more likely that that wolf will become a pack leader.

CONNOR MEYER: Results in this finding were pretty significant in that Toxoplasma gondii infection was 46 times more likely to predict that a wolf becomes a pack leader and 11 times more likely to predict that a wolf would disperse from their kind of home, their natal pack.

FOLKENFLIK: That's Connor Meyer, a grad student at the University of Montana who authored this study along with Kira Cassidy, a research associate at the Yellowstone Wolf Project. You heard right - their research indicates that a wolf is 46 times more likely to lead its pack if it's been infected with this parasite. Meyer says these results indicate how influential even the tiniest organisms can be.

MEYER: A lot of research is done on wolves and elk and cougars and deer and kind of the big things that we can see. Maybe it's actually the little things that can be affecting individuals and affecting ecosystems.

FOLKENFLIK: Cassidy and Meyer decided to look into the role this tiny parasite might play in Yellowstone's ecosystem, where they already have nearly 30 years of data on the park's wolves. Studies have shown this parasite can change the behavior of a mouse so that it takes more risks. Meyer and Cassidy wondered if the changes that show up in infected mice might also show up in wolves.

KIRA CASSIDY: We tested a bunch of different things. We wanted to know if wolves were taking bigger risks, so we wanted to know are they more likely to disperse or become pack leaders? As it turns out, wolves that were testing positive for Toxo were more likely to disperse and more likely to become pack leaders than wolves that were negative.

FOLKENFLIK: I want to be clear this doesn't necessarily mean they're good leaders.

CASSIDY: Maybe they're poor leaders. We actually don't know if they're doing a good job or not. But I think the quality of the leadership, once it reaches that position, is going to be one of the most interesting things to look at next.

FOLKENFLIK: Worried that these findings could foreshadow a possible wolf-zombie apocalypse? Well, the parasite causes the temporary disease of toxoplasmosis in all mammals, including us. And while its effect on humans is difficult to track, maybe you've had a sudden craving to - I don't know - attend a leadership conference, to network, to lead a wolf pack. It may not be you. It may just be a parasite.

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