It’s common to find a crazy cat lady in almost any neighborhood. This is the type of woman who fills her house with cats and often doesn’t care about her own appearance. People often mock and tease such crazy cat ladies, but there’s a scientific reason for why people go crazy for cats.

A protozoan that in cat feces, called Toxoplasma gondii, can actually infect a person and alter their brain. Researchers found that this parasite actually affects the brains of rodents, making the rodents less fearful of cats.

This has the added benefit (for cats) to catch rodents easier, but for humans, this likely encourages people to care more for cats to the point where they devote their whole lives to caring for a cat. Most likely, cats are using biological warfare against humans to convert the human race to their own personal servants. Don’t worry about robot overlords taking over humanity. Worry about cats instead.

To read more about how parasites can make people more likely to like cats, click here.