Are you ever really alone?
Even when you think you are sitting at home alone, you are still in the company of a great number of living things. Bacteria live on you and in your body, and constantly protect you and also, occasionally, cause you to become ill. Mites that are spread everywhere, from the chair you sit in to your carpet, to the air you breathe. Moulds and fungi begin reproducing on foods left out in the open in your kitchen for even a few hours—all of these constitute a different world with its own unique lifestyles, nutritional systems and structural features.
