Why we like what we like: A scientist’s surprising findings

Your genes, your germs, and your environment all may influence your tastes in food—as well as partners and politics.

There may be nothing more self-defining than our tastes. Whether in food, wine, romantic partners, or political candidates, our tastes represent our identity. So it made sense to me that my likes and dislikes were formed through careful deliberation and rational decision-making—that is, through choices where I wielded some control.

Then I became acquainted with Toxoplasma gondii. In my research at the Indiana University School of Medicine, I observed how the single-celled T. gondii parasite can change the behavior of the host it infects. It can make rats unafraid of cats, and some studies show that it may cause personality changes (such as increased anxiety) in humans.

These studies made me wonder if there are other things happening under our radar that