It’a an accepted statement that men, as a species, are more aggressive than women. As individuals, it’s anybody’s guess. When I was in Army ROTC, our best cadet commander was a woman. But generally speaking, I’d say that roughly 80%-90% of the starting reaver pop was male. Reaver women caught alone or outnumbered were most likely overpowered and raped to death. There would be no pregnancies. No pregnant woman would be able to escape a mob, and no intact womb would survive the constant assault that would follow capture. In the horribly unlikely event of an actual birth, the baby would probably end up as lunch for the mother. So, despite the quick shot on Lilac of a reaver woman attacking a villager, there would be no reaver women by the time of Firefly or Serenity. Out of 30,000 starting pop, we’re down 24K-27K after the women are killed.

Obviously, reavers can work together to some degree. Any spaceship needs a minimum crew, even if they aren’t keeping the ship in good shape. And the reavers attacking on Lilac, and in Mr. Universe’s base were cooperating. But these guys are hyper-aggressive. It’s a good bet that most disagreements or arguments would end up as fights to the death, with the loser ending up as the victory meal. And there would be LOTS of arguments. Remember the arguments between different orc tribes in LOTR? Forget Marquis of Queensbury rules. And forget medical care. Remember the gray miner/minor creatures in Galaxyquest and their treatment of the injured? I think it’s VERY generous to say that by the time of Firefly and Serenity, the total reaver population is down to half, or roughly 15K, all male. Realistically, probably a lot less.

Which brings us to Mal’s misbevaving stunt of luring the reavers at Miranda in a chase. Going by the Complete and Official Map of the Verse, the reavers are probably clustered at the Burnham-Miranda lagrangian points, and in orbit around Miranda and Caliban. Some of those ships were huge, and had to have corresponding populations. The highest concentrations were probably at the B-M L1 and L2, with smaller pops being at the L4 and L5, and the smallest being at L3 since it’s on the opposite side of Burnham. Reaver pops were probably also at all the lagrangian points that correspond to Miranda and Caliban. So, Mal pulls away most, if not all, of the reavers around Miranda. Since reavers don’t surrender or take prisoners, any who chased Mal ended up dead since we know that the Operative’s troops and ships won that battle. The reavers that did not chase Mal were probably the at the B-M L4, L5, L3; and at the Miranda-Caliban L4 and L5 positions. Mal took the biggest chunk of the population, maybe 9K-10K, leaving roughly 5K alive.

They’re going to be spread out. Less chance of interaction means longer lives. But remember that the Pax was 12 years ago. The average age of a reaver will be early to mid thirties. There won’t be any old reavers. This will not be a culture that values wisdom. Anyone who can’t make and swing his own axe will end up as jerky. Reaver encounters will taper off to near zero over the next two decades. And that will end the reaver threat unless the Alliance starts running Pax experiments again.