A group mind, hive mind, group ego, mind coalescence, or gestalt intelligence in science fiction is a single, collective consciousness or intelligence occupying many bodies or entities. Its use in literature goes back at least as far as Olaf Stapledon's science fiction novel Last and First Men (1930). A group mind might be formed by telepathy, by adding brain-to-brain communication to ordinary individuals, or by some unspecified means. This term may be used interchangeably with "hive mind". A hive mind is a group mind with almost complete loss (or lack) of individual identity; most fictional group minds are hives. The concept of the group or hive mind is an intelligent version of real-life superorganisms such as an ant colony or beehive, and consequently, insectoid aliens such as Zerg and Ceph often have such a mind.