Related on TestTube
Do We Really Need Bras?
How Sleep Can Improve Your Sex Life
DNA that only females have (Science Daily)
"In many animal species, the chromosomes differ between the sexes. The male has a Y chromosome. In some animals, however, for example birds, it is the other way round. In birds, the females have their own sex chromosome, the W chromosome. For the first, researchers have mapped the genetic structure and evolution of the W chromosome."