According to Charles Berg, the depictions of aliens in science fiction which became more popular during the 1980s represented American fears of immigrants (the "other"). In "Aliens", this can be seen in the Caucasian single mother (Ripley) confronting the dark-skinned alien queen with an endless brood. Tammy Ostrander and Susan Younis also note fears of overcrowding, dwindling resources and pollution, suggesting the alien queen demonizes motherhood and make it less attractive. She represents mindless, unchecked maternal instinct spawning armies of children, regardless of the lives which must be sacrificed to ensure their survival. Despite imminent destruction by the colony exploding, the queen continues to reproduce. The aliens' life cycle taints the reproductive cycle. Creation involves rape, and birth involves a violent death. In destroying the aliens and their queen, Ripley rejects the unchecked proliferation of their species and sets an example for her own.