"There is a species of slave-making ant that lives in the Sagehen basin. Slave-making has evolved in ants nine separate times, so it apparently works.
Polyergus breviceps are obligate social parasites, meaning that they simply can't live without their slaves: they have lost the ability to dig tunnels, gather food, care for their babies. All they do is hang around, being taken care of until it's time to go out on another raid.
The video shows Polyergus breviceps [red ants] stealing brood [eggs & pupae] from nests of the host species, Formica argentea [black ants].
Many stages of a raid are shown: the nest before a raid with no red ants apparent [they don't work except to raid]; the initial red scout heading out, the red column advancing; winged red reproducers accompanying the column & mating along the way; black ants trying to block the entrances to their home; red ants unblocking the entrance, then taking brood from the target nest; racing back to the home nest where the black ants take over care & sometimes carry or drag the exhausted red ants.
The new black brood will hatch out & acquire the scent of the new home nest, then go right to work taking care of the red queen's eggs.
Meanwhile, the mated reproducers will lose their wings & attempt to find a black ant nest then kill its black queen, taking over egg laying duties & converting the nest to a red ant nest with black slaves. There will be no more black ant eggs produced in these attacked nests. "