article_snippet.sent: Ashley (left) and Mary-Kate Olsen (right) are two of the most famous twins in the world and despite Ashley (left) and Mary-Kate Olsen (right) very similar appearances Ashley (left) and Mary-Kate Olsen (right)
article_snippet.sent: are not actually identical twins .
article_snippet.sent: Not all monozygotic twins (i.e. twins born from a single fertilised egg) are truly identical.
article_snippet.sent: Some are ‘mirror image’ twins.
article_snippet.sent: But many identicals are truly identical in ways we are still uncovering.
article_snippet.sent: Obviously, identical twins share facial characteristics and body shape.
article_snippet.sent: But identical twins also share virtually identical DNA, meaning identical twins are more closely related to each other than to anyone else, including identical twins parents or identical twins own children.
article_snippet.sent: Joel (left) and Benji Madden (right) are identical twins, it's likely that identical twins will have grown more alike over time as identical twins identical DNA asserts it .
article_snippet.sent: Identicals also share the same blood group, the same hormones, the same serum proteins; both are alike in heart rate, blood pressure, brain waves, respiratory rate and digestive process.
article_snippet.sent: Hospitals in America in the past have advised parents to discreetly tattoo one twin — with a tiny dot, or mark on a heel — so that in future the children can be differentiated.
article_snippet.sent: Parents often refuse, believing Parents will be able to distinguish Parents twins as Parents age (not least, by dressing their twins differently).
article_snippet.sent: This, however, can be a mistake because twins can grow more identical over time (as twins identical DNA asserts This, following different levels of nourishment in the womb).
article_snippet.sent: And twins often end up being dressed in exactly the same clothes anyway, lest one become jealous of the other getting ‘better’ treatment.
article_snippet.sent: Take the classic example of twins separated at birth.
article_snippet.sent: Some parents of twins have reported Some parents of twins children having identical dreams.
article_snippet.sent: Some parents of identical twins have observed Some parents of identical twins having identical dreams or even suffering pain in the same parts of the body .