The dust had settled. The Earth was in ruins. But the alien Invaders had been defeated. What was once a population of over 5 billion people had been reduced to just over a billion. The survivors would rebuild, but it would take time. 

The surviving world leaders had gathered for a conference in an undisclosed location, and away from the press. The metropolitan centers of every major industrialized country had been decimated. A census was initiated to get an accurate count of the survivors. The population was split equally between men and women. Scientists determined that there was enough genetic separation between the remaining people to ensure humanity survived.

The women who were pregnant at the time of attack and survived were able to give birth to healthy, normal babies. And as soon as the scientific community saw that there were no mutations, they knew that their prediction for man’s survival was accurate.

It wasn't until about five years after the attack that scientists noticed something was off. The children who were conceived after the invasion showed marked differences, By the age of three, females were much taller and stronger than males of similar age. In fact, females at that age were taller and stronger than boys entering first grade. Scientists couldn't understand it. Tests were conducted, and no explanation was found.

As the girls entered first grade they were taller and stronger than their fathers. Soon, parents of the girls conceived after the attack became very wary of getting their daughters upset. 

Reports surfaced of fathers ending up in the hospital with broken bones inflicted by their children. Older siblings, especially brothers, basically became servants to their younger sisters. And schools became segregated, because boys up to and including high school seniors were bullied by first grade girls. The schools that the girls went to were out of the way, with no chance of interaction with any males.

By the time girls turned nine, they were more than a foot and a half taller than their fathers. Special houses had to be built to accommodate their sizes. Bigger vehicles were rushed into production in order for the girls to be transported.

 Discipline was no longer in the hands of the parents. In fact, parents were at the mercy of their daughters. It was not uncommon for mothers, fathers, and brothers to walk around gingerly after being disciplined by a nine year girl.

By the time the girls reached the age of 13, they stood about three feet taller than their fathers. Some girls ruled their house with an iron fist. Questioning orders, or perceived backtalk was met with swift punishment.

Some were more understanding to a point, but everyone in the family knew who was in charge. 

Scientists finally discovered the cause of the girls’ growth. Residual particles from the aliens’ weapons had mixed with the energy released from the world's nuclear weapons that were used to try and destroy the aliens had caused undetectable mutations in the genes of females conceived afterwards. This allowed for the dramatic size increase in females. As far as scientists could determine, this was now permanent. The mutations only affected the female population. And it affected all females, even those born with a male twin.

By the time girls reached the age of sixteen, they reached their final height of around fourteen feet on average. Sex with males became impossible because it became too dangerous for the boy. Broken bones, permanent paralysis, and even death befell the male. Soon it became necessary for girls to engage in sexual activity with specially made toys built just for them. If reproduction was needed, in vitro fertilization was the only way to go.

Soon, after the first girls reached eighteen, society began to change. Men were becoming aware that their place in the world was going to change and change quickly. As more and more girls became of age, they were able to intimidate men into submission. Soon, laws were changed allowing females of the age of 18 to run for political office, and with ever increasing numbers, it wasn't long for other laws to be changed. 

Soon, men lost the right to vote, and lost positions of power in business. Men became second class citizens within the blink of an eye. There were isolated communities where the old ways still existed, but they became fewer and fewer, until eventually they were gone forever. And that was the true effect of the aliens attacking Earth.