At least three of the Five Families might be glad to see Earth humans burst into space on their own.

Lunarians are not that different from Earth humans.

"Earth humans have an expression that covers such an eventuality," the first officer said archly.

They follow a forgotten path under the city out of Eden and into the green Earth humans have been cut off from for so long.

Also, it would seem Galadorians have a longer lifespan than Earth humans.

On Earth early humans built extremely complex mounds, some in the shape of serpents.

"Earth humans cannot survive long on the surface without drugs or shielded environments," the admiral said.

All told, some four billion Earth humans were killed.

The humans are actually not the same species as Earth humans but a species that is remarkably similar.

The Invaders in this case are humanoid, very similar to Earth humans.