In one case, identical twin babies (Oskar and Jack) were raised in extremely different cultures. The two were born in Trinidad and separated shortly after birth. After that, their childhoods were very different.

The mother took Oskar back to Germany, where his grandmother raised him as a Catholic and a Nazi youth. Jack was raised in the Caribbean as a Jew, by his father, and spent part of his youth on an Israeli kibbutz.

But similarities started cropping up as soon as Oskar arrived at the airport. Both were wearing wire-rimmed glasses and mustaches, both sported two-pocket shirts with epaulets. They share idiosyncrasies galore: they like spicy foods and sweet liqueurs, are absentminded, have a habit of falling asleep in front of the television, think it's funny to sneeze in a crowd of strangers, flush the toilet before using it, store rubber bands on their wrists, read magazines from back to front, dip buttered toast in their coffee... Bouchard professed himself struck by the similarities in their mannerisms, the questions they asked, their "temperament, tempo, the way they do things." (Holden, 1980)

But feel free to keep assuming you're better at this than the guy who did this for a living.