MZ twins are generally assumed to be genetically identical, although some genetic and epigenetic differences have now been described. A newly published finding that phenotypically concordant as ...

At the core of many people’s fascination with twins is the belief that, at least in the case of identicals, their minds are as similar as are their bodies ... Many identical twins do show ...

Conjoined twins occur when identical twins have fused bodies before they are born. This condition has also been known as "Siamese twins," now considered an inappropriate, outdated term.

Obviously, genes are not the only factors that determine phenotype - after all, even identical twins are not exactly alike. But what can armadillos teach us about being an individual? One way to ...