The New York City subway is a germ-filled place.

Thanks to a new study, we now know that we share our commutes with around 600 different species of bacteria — including some that have been linked with everything from food poisoning to meningitis.

Other, far less harmful subway residents include the microbes found in mozzarella cheese and bacteria found in garbanzo beans (the main ingredient in falafel), which reveal a striking pattern of commuting-while-snacking.

While there are questions about whether this kind of DNA fingerprinting yields accurate results, the new study, led by Weill Cornell Medical College geneticist Chris Mason, includes a host of irresistibly fascinating information about the microbes that are sharing your subway ride. Here are three of the most interesting things we learned:

1. South Ferry still looks — on a microbial level, at least — like it's under water.

If you've ever stopped at or passed South Ferry, the southern Manhattan station that was flooded during Hurricane Sandy, you might be interested to find out that most of your fellow bacterial commuters are from under the sea.

Yes, two full years after Hurricane Sandy, the majority of the microbes lining the walls of the South Ferry Station still resemble the bacteria we typically associate with fish species and marine environments. Ten of the bacterial species the researchers found in South Ferry didn't exist in any other station in the city.

While the bacterial environment at South Ferry reveals how hardy certain microbes can be, the bacteria at Penn Station reveal how rapidly that environment can transform based solely on who travels there and how often.

2. The bacterial diversity of Penn Station changes by the hour.

Cell Systems/"Geospatial Resolution of Human and Bacterial Diversity with City-Scale Metagenomics" "The dynamics of Penn Station suggest that, even on an hourly basis, there is a vast bacterial ecology that is constantly shifting around commuters," the researchers write in their paper.

While one type of bacteria — Pseudomadaceae, a class of bacteria typically found in the soil — is found most often between 11AM and 1PM, for example, another class of bacteria, Moraxellaceae, was more prominent by the end of the day, around 5PM.

3. A large portion of the bacteria in the subway is from a mysterious source.

Another important finding from the new research is that we still know astoundingly little about the types of bacteria that populate the subway, where they come from, and why they thrive there. Of all the microbes the researchers discovered during the course of their 3-year-study, nearly half don't match any known type of species.

Before you freak out, you should know this: Exposing yourself to all these mystery vermin isn't nearly as bad for you as it sounds.

In fact, several recent studies suggest that people who grow up in bacteria-rich environments — like those that include different animals and insects — are better protected from allergies and respiratory infections than people who spend their early lives in "clean," highly urban ones.

You can check out the full interactive map the researchers created to accompany their study here.