A taste for danger
A parasite who's boss
Hyenas and lions
Hyenas in Kenya
Walking towards their demise
A surprise, but not so much
Cubs and adults
Humans and toxoplasma
Behavioral effects on humans
Good in business
Danger for pregnant women
Cats are perfect hosts of the parasite
Cat and mouse fight
Explanation of the 'brave' mice
The voice of experience
Real impact
This parasite controls the minds of hyenas - and humans too
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A taste for danger

Surely you know someone who feels better the closer they get to a risky situation.

This parasite controls the minds of hyenas - and humans too
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A parasite who's boss

In this gallery, we will tell you the case of a group of hyenas who suddenly began behaving differently from the usual. It wasn't because they felt like it, but because they were under the control of a parasite in their bodies.

(Photo: Chuttersnap / Unsplash)

This parasite controls the minds of hyenas - and humans too
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Hyenas and lions

A study published in the scientific journal Nature Communications suggests that the offspring of hyenas infected with Toxoplasma gondii move dangerously close to lions. The ones who are not sick, keep a safe distance.

(Photo: Zdenek Machacek / Unsplash)

This parasite controls the minds of hyenas - and humans too
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Hyenas in Kenya

The data were collected in decades-long observations of these animals in the Masai Mara National Reserve in Kenya.

This parasite controls the minds of hyenas - and humans too
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Walking towards their demise

While healthy hyenas went only within 300 feet of the lions, the sick ones dared to go up to 50 meters and, of course, their chances of dying were four times greater.

This parasite controls the minds of hyenas - and humans too
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A surprise, but not so much

Ecologist Kay Holekamp, co-author of the aforementioned survey, acknowledged to the National Geographic website that she was surprised by something that was at the same time "incredibly evident."

 

This parasite controls the minds of hyenas - and humans too
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Cubs and adults

Although hyenas are natural predators, in the first years of life they are protected from other animals by adult hyenas. They are not hunting, but without supervision, they might roam too close to more dangerous species.

This parasite controls the minds of hyenas - and humans too
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Humans and toxoplasma

And then there's this striking fact about toxoplasma and human beings. The single-celled protozoan has been found in 1/3 of the human population.

(Photo: Ryoji Iwata / Unsplash)

This parasite controls the minds of hyenas - and humans too
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Behavioral effects on humans

There are reports that this parasite has led infected people to be more reckless, even causing traffic accidents. On the other hand, this "encouraging" effect has also had good consequences for some.

(Photo: Laura Gariglio / Unsplash)

This parasite controls the minds of hyenas - and humans too
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Good in business

Proof of this is a study published in the National Center for Biotechnology Information (USA) which shows that people with toxoplasmosis have a greater probability to develop entrepreneurial activities than others who do not have the disease.

(Photo: Humphrey Muleba / Unsplash)

This parasite controls the minds of hyenas - and humans too
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Danger for pregnant women

Although most people who suffer from toxoplasmosis, an illness caused by toxoplasma, have flu-like symptoms, the illness in pregnancy can cause malformations in the foetus.

(Photo: Taylor Wright / Unsplash)

This parasite controls the minds of hyenas - and humans too
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Cats are perfect hosts of the parasite

In fact, it is recommended that pregnant women avoid contact with cat feces or urine. That's because felines are the ultimate hosts of toxoplasma. It is in their bodies that this parasite reproduces.

(Photo: Mel Elias / Unsplash)

This parasite controls the minds of hyenas - and humans too
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Cat and mouse fight

Toxoplasma also manipulates infected rodents to act risky among domestic cats.

(Photo: Alexandr Gusev / Unsplash)

This parasite controls the minds of hyenas - and humans too
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Explanation of the 'brave' mice

Infected animals lose their aversion to the smell of their predators' urine and, as a consequence, they lack any fear of approaching them.

This parasite controls the minds of hyenas - and humans too
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The voice of experience

This effect may have occurred in the hyena pups from the study we cited. In any case, the survivors seemed to have learned, over time, about the danger of provoking a lion. They've started to do it less and less.

(Photo: Bhargava Srivari / Unsplash)

This parasite controls the minds of hyenas - and humans too
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Real impact

“It is a parasite that people think is mostly benign, especially in humans, but when we look at some of these effects, Toxo can have major impacts on human behavior, including at the social level,” researcher Stefanie Johnson explains to National Geographic.

(Photo: Matthew Henry / Unsplash)

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