Bacteria are among the most numerous organisms on earth, explains Microbe World. Bacteria exists virtually everywhere on earth. Bacteria can be found in the air, soil, water, on plants, on animals and even on the skin of human beings.
Part of what makes bacteria so plentiful is their ability to inhabit a variety of different types of environments. Some bacteria thrive in extremely hot environments, such as those found in boiling-hot sulfur springs and geysers. Other types of bacteria are capable of surviving sub thermal freezing temperatures buried under many sheets of ice, such as those conditions found in the super-cold Antarctic lakes. Microbes that live in these extreme conditions are called extremophiles.
One single teaspoon of top soil contains as many as one billion bacteria cells. The human mouth alone harbors more than 500 different species of bacteria. Each square centimeter of skin on the human body contains around 100,000 bacteria. Bacteria can survive not only in extreme conditions, they can also survive on surfaces for long periods of time. While removing bacteria from day-to-day life is not feasible, washing hands regularly and disinfecting surfaces you come in contact with on a regular basis helps reduce the amount of bacteria that enters your body.