"But frankly, this mostly falls into the 'Get a load of this, can you believe what nature has come up with?' category."
Research from several different studies in several different fields has flagged a parasite called Toxoplasma gondii, which is excreted by cats in their feces, as a contributor to car crashes, suicides, and mental disorders such as schizophrenia, due to the way researchers hypothesize it influences the fear and anxiety centers of our brains.
Any interesting case all sorts of people are researching, including parasitologists, psychiatrists, evolutionary biologists, and neuroscientists.