Research has shown that girls who get their period earlier on are at higher risk of breast cancer, depression and teen pregnancy. There are a lot of factors that can contribute to reaching puberty earlier, including obesity, nutrition, and exposure to chemicals. Now, there's another factor that appears to trigger earlier onset of puberty: fathers -- specifically fathers who are addicted to drugs or alcohol, are abusive, or are involved in criminal activity.

It's not so much the living with an abusive or drug-using father, however, that spurred the early development as it was his leaving. The theory is that the girls are responding to a "window of opportunity" by developing faster. "In the world in which humans evolved, dangerous or unstable home environments meant a shorter lifespan, and going into puberty earlier in this context increased chances of surviving, reproducing and passing on your genes," said Professor Bruce Ellis who worked on the study.

It seems to me that the practical application of this information is not that abusive fathers should necessarily stick around, but that fathers shouldn't be such a problem in the first place. This is just one more reason to work really hard to be the best father possible.