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 ...

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 ...

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 ...

Identical and fraternal twins can provide insight into the effects of nature and nurture on factors such as eye color, intelligence, and autism. The environment can sometimes "override" genetic ...

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 ...