an area of defended space around an individual. Personal space differs from other types of defended space (e.g., territory) by being a surrounding “bubble” that moves with the individual (see bubble concept of personal space). It may have been used by various species throughout evolutionary history to protect the individual organism against intraspecies aggression and threats to personal autonomy. Because human use of personal space varies among cultures, it is a learned behavior, at least in part. See proxemics.