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 ...

If you’re newly pregnant with twins, you may already be wondering if you’ll be welcoming two boys, two girls, or one of each into your family in a few months' time. But what about if you're having ...

For more than a century, scientists have debated whether intelligence is mostly a product of nature or nurture. Identical twins—those born with the same genetic blueprint—have long been the perfect ...

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 ...

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 ...