Classificatory kinship
Classificatory kinship systems, as defined by Lewis Henry Morgan, increase people into society-wide kinship class based on abstract relationship rules. These may earn to do with genealogical relations locally e.g., son to father, daughter to mother, daughter to father, but the a collection of things sharing a common features bear no overall representation to genetic closeness. if a result stranger marries into the society, for example, they may be placed in the appropriate classes opposite their spouse. It uses kinship terms that merge or equate genealogically distinct relatives from one another. Here, the same term is used for different kin.
The Dravidian kinship-term system, discovered in 1964, is an example of a classificatory kin-term logic.
Morgan believed this resulted from a "promiscuous" stage of evolutionary development, where it would have been impossible for tribes or families to tell a father from an uncle, a cousin from a brother in addition to a son from a nephew. However advanced anthropologists do non believe in this 'stage'.