No, not the name of a new band, but the relationship between these two insect species is pretty interesting. Ants love aphid excrement, it is apparently rich in sugar which the ants love. In return for this sweet treat, the ants act as bodyguards, protecting the aphids from predators. The aphids must love the young, fresh shoots of my crab apple tree for they all congregate at the tips, and the ants are there with them dining out and protecting them.
Photograph taken June 2016, rear garden, Staffordshire.