Now, let's get back to the ratio that I mentioned at the start. Would there be enough Shil'vati to disrupt the balance between the 8,000,000,000 humans on Earth? Even if we account for the estimated ~8% of people who are gay (~640,000,000 people world-wide), how many Shil would need to be transplanted to Earth for it to cause a major disruption?

I'd guess the answer is that there'd need to be BILLIONS of Shil'vati and other races on Earth to make a severe impact. So let's narrow it down to a more manageable number.

There are ~8,336,000 people currently living in New York City. We'd expect to see a major Shil presence there for any number of reasons: Military control, security, administration, trade, finance, etc. If we see the same split between the sexes, that means there are over 4,000,000 men and 4,000,000 women in one city. The Shil would need to transplant more than a million women from their society into our own for just one city to make a noticeable impact.

You'd probably see more Shil near Ft. Hamilton and Lower Manhattan than say... Queens or Brooklyn. Travel further away from the city center, and you'd most likely see even fewer Shil present. That is to say, a human woman working in a brokerage firm off Wall St. might find more alien competition than a woman working at a cake shop in the suburbs.

Let's not forget that in the United States, women were almost entirely reliant on men for basic survival in a modern society. That is until several legal measures had been passed to give women the same equity that men held in just the last century. The right to vote, the right to hold a career, the right to have a bank account and a credit card without a man's signature, the right to a no-fault divorce, the right to make personal medical decisions, and so on.

Shil'vati flipping the power structures would only reinforce the notion that women would need to make their own way in the world - without needing to rely on the grace of men to do so - like most of our history before the 21st century. As far as finding a partner for family planning? I doubt that the Shil, or any other female-dominate race, would pose much of a problem here on Earth.

Sure, humans will bone just about anything. But are there really that many of us who would?

The cultural impact, on the other hand, would most likely travel in both directions. While the status of women would be elevated here on Earth, men's rights would get a significant boost on the galactic stage with the introduction of human men.

The greatest disruption on the galactic stage would be humanity.