Laurie Clarke delves into the devilishly complex forces that shape our personalities – and the new research revealing ever ...

Growing up as identical twins in the New Jersey suburbs, Erica Hyman and Nancy Marciniak did everything together. From playing the same sports to wearing the same prom dress (Hyman found it first; ...

Identical, or monozygotic, twins develop from the same fertilized egg that splits into two. These twins are the same sex and share the same genes. Sometimes called paternal twins, identical twins ...

In 2004, Michigan police found that DNA recovered from a crime scene matched that of Jerome Cooper, a notorious criminal. But what seemed like an open-and-shut case got complicated when the cops found ...