Here's a fairly interesting link: Students who have been exposed to the Toxoplasma gondii parasite are 40 percent more likely to major in business than those not exposed. That’s according to a study recently published in the Proceedings of the Royal Society B.  

First things first, what is Toxoplasma gondii? It is a single-celled parasite that is thought to affect around a third of people on the planet, though this varies by region, with people in France (81 percent) far more likely to be infected than people in Japan (7 percent) or the US (20 percent). It can be caught from eating poorly cooked meat or from drinking contaminated water – and from your cat's feces.

The good news is that unless you are pregnant or have a compromised immune system, the parasite shouldn't make you sick. But it has been linked to a variety of health conditions and behaviors, including depression, dementia, schizophrenia, anger management problems, and even a propensity for bondage. 

For the latest study, researchers took saliva tests from 1,495 US students. They found that those who had been exposed to the virus were 1.4 times more likely to major in business and 1.7 times more likely to pick an emphasis in "management and entrepreneurship", in comparison to any other business-related specialties. That's a pretty significant difference.

This propensity to select business and more entrepreneurial pursuits was supported by a second batch of saliva tests, this time on 197 business professionals attending career events. Those who tested positive were 80 percent more likely to have set up their own business than those who tested negative. 

When looking at it from a national scale, the team found that countries with a higher prevalence of T. gondii also appeared to have higher levels of entrepreneurial activity. That's based on 25 years' worth of data from the  Global Entrepreneurship Monitor of entrepreneurial activity. Citizens from these countries were also much less likely to say a "fear of failure" prevented them from starting their own business.

So, why might this be? The link is correlational, not causational, so should be taken with a big pinch of salt. Plus, while there are many studies to suggest T. gondii can affect human behavior, there are several others that call baloney on this research or imply the links have been overstated.

However, there is some evidence that the virus can make its hosts more risk-tolerant, reducing their fear of failure and making them reward-seeking – both perhaps useful traits if you're considering starting your own business. Studies have also found that mice infected with the virus not only move slower and more frequently, but lose their fear of – and can even become attracted to – cat pee. 

In humans, however, it's only a link for now and more research needs to be done.