Add Yahoo as a preferred source to see more of our stories on Google. A century’s worth of twin data reveals that when schooling differs, identical twins’ IQs can diverge as much as unrelated people’s ...

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 ...

The similarities may be uncanny, but identical twins aren't exact copies of one another ...

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 ...