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 ...

Fascination with twins and what twin studies tell us about human nature is universal. There is no question that behavioral and medical science advances have happened largely because twins yield a ...

I never believed in love at first sight until I met my now-husband. I couldn't recognize him from his identical twin brother over the phone. We ended up having fraternal twins, and I got to experience ...

When we think of identical twins, we often imagine mirror images — same face, same smile and perhaps even the same talents. But what surprises many is that these genetic carbon copies can have ...

After identical twin sisters from Delaware married identical twin brothers from Tennessee, the children they are raising together share in a rare biological phenomenon. When identical twin sisters ...

It makes sense that identical twins would have the exact same DNA, right? Spoiler alert: Not always! Here's why. Identical twins (also called monozygotic or MZ twins) are conceived when a single sperm ...

From Romulus and Remus—the myth of the twin brothers who founded the city of Rome—to the synchronized speech of Australia's "Twinnies" Paula and Brigette Powers, identical siblings have long inspired ...