>>Environment?
Heredity isn’t everything.<<
It apparently starts in the pre-birth environment - the finger prints are apparently extremely similar but slightly different. Apparently difference in nutrition, womb position and blood pressure have slight effects on fingertip growth rate and thus cause tiny fingerprint differences.
Later in life environmental differences are even bigger - and things like lines in the face and body weight can diverge even more.
Fascinating topic though.
You might be onto something there. My brother and I shared the same womb. I weighed one pound more at birth and through life I've always been 10+ pounds heavier.
Another thing, while in the womb, we decided to be just adorable... some things never change. :)