30 mind-blowing facts about the microbes that live inside of you

The human microbiome is as elusive as it is important. You can't see it, but it's teeming with trillions of bacteria, viruses, fungi, and other microscopic organisms that line vital body parts such as your intestines, mouth, and skin.

These organisms have evolved with humans for hundreds of thousands of years, and as we probe deeper into their varied roles in the human body, we're gaining valuable insight into their essential roles in digestion, the immune system, cognition, and certain diseases.

There's still much we don't know about the microbiome, but the past 20 years of research have revealed some surprising facts about these tiny critters in our bodies.

Here are 30 eye-opening facts about the human microbiome, sourced from The American Museum of Natural History's new microbiome exhibit, The Secret World Inside You. The exhibit runs in NYC November 7, 2015 to August 14, 2016.