First I would like to call your attention to a new and emerging science. It is basically the study of how viruses can affect our behavior. It
postulates that in times gone by the human race was hit with viruses that programmed us to be, well human. I don’t know the name of this field of
study, and Google provides limited results.
Anyhow this is how I remember it being explained. Once we get a virus it creates changes that are retained for our entire lives and also passed to all
future generations. Based on the below studies it has been shown that certain viruses can change just about anything about us.
What’s worrisome is that they have been creating custom viruses that create distinct changes in rats and voles.