The pirate ants that keep slaves

Not far from you, ants are fighting for their freedom. They have been victimised by "slave-maker" ants, which subjugate other ant species to do their work for them. To recruit slaves, the slave-makers deploy troops that conduct raids on surrounding colonies. The system can be terrifyingly effective, in a sense akin to the horrific methods humans have used to keep slaves in line. The enslaved ants pay the ultimate price: they do not get to reproduce. But the slave-makers do not get it all their own way.
 Some of their victims are fighting back. This battle is being fought, not just from day to day, but over evolutionary time – and nobody yet knows how it will end.