7 Theories About You That Will Make You Question Everything

6. You're A Symbiote

We all know that you've got a little ecosystem of bacteria living on your body, in your gut and even on your freaking eyelashes. We have a symbiotic relationship with these colonic colonies as we provide them with a steady supply of food and they help us to absorb nutrients and even produce nutrients of their own such as Vitamin K.

If you got rid of these, you be in pretty serious trouble, but there is another organism living much deeper within you - within your very cells.

The mitochondria are the powerhouse of the cell. They're also not human.

Mitochondria, which make multicellular life possible in the first place, have different DNA to the rest of the cell, which must mean that they started out on a different evolutionary path. At some point in the history of life on earth, a symbiotic relationship sprang up between two single celled organisms, which merged together to form a completely new entity in a process called symbiogenesis.

Mitochondrial DNA is passed down through generations just like our "human" DNA, in a sort of parallel family tree.