I have not applied the scientific method to Zodiac signs. Has anyone yet?
Not exactly but there is a paper that links birth month to personality factors, possibly due to the effects of exposure to seasonal flu or some other such factor (sunlight exposure and vitamin d would be one guess of mine, I think not demonstrated at all in the paper iirc) during early development.
I can dig it up if you are interested and can't find it.
Now back to your regularly scheduled troll circus.
Correct, all these environmental factors influence our epigenome (software) while the DNA (hardware) is not affected.