Fraternal or dizygotic twins develop from two different eggs fertilized by separate sperm; they generally share about 50 percent of their genes. Therefore, fraternal twins are essentially like typical ...

What's the meaning of fraternal twins? Fraternal twins come from two separate, fertilized eggs that develop in the womb at the same time, each with their own placenta and amniotic sac. Like any ...

I was on the Today Show today, May 7, 2008. The taped session focused on studies from two separate laboratories. The first study concerned research on twins’ social relationships, conducted in my lab ...