So everyone in Silicon Valley, basically

Toxoplasma gondii is a protozoan parasite carried by cats. It can infect people through contact with cat faeces, poorly cooked meat, or contaminated water, and as many as one-third of the world’s population may be infected. The parasite doesn’t make us feel sick, but it forms cysts in the brain where it can remain for the rest of a person’s life. Some studies have linked infection with the parasite to slower reaction times, schizophrenia, bipolar disorder, suicidal behaviour, and explosive anger.

Now an assessment of almost 1300 US students has found that those who had been exposed to the parasite were 1.7 times more likely to be majoring in business...  The team behind the study say their data suggests that the parasite may be involved in reducing a person’s fear of failure and high-risk, high-reward ventures. 

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