-microbes generate at least half the oxygen that we breath
-microbes first appeared on earth, 3.5 million years ago
-our mouth is inhabited by over 600 species of microorganisms
-less than 5% of the estimated 2 to 3 billion microbial species have been discovered
-there are more microorganisms on your hand than the population of planet earth
- Microbes can't be seen by the naked eye
- there are approximately 100 trillion microbes in and on our bodies
