In almost all primitive societies as well as among the highly sophisticated Hindus of India, we find the prevalence of Clan System.
A clan may be conceived as an enlarged unilateral kinship group that rests on the fiction of common descent from a founding ancestor who lived so far in the distant past as to be mythological.
Though the actual origin of the clan is lost in the hoary past, the members of a clan believe in blood relationship among themselves and as such they maintain the rule of clan-exogamy.
This common descent, as in the case of the Hindus, is traced from some sages (religious preceptors) of the past like Sandilya, Kashyap, Varadwaj, Gautam, while the tribals trace it from their respective clan-totems which are invariably non-human in nature like tiger, tortoise, snake, birds, fish, leopard, paddy stalk, tree.
Both the advanced Hindus and the tribals show respects to their founding ancestors. The tribals do not touch, kill, or eat the flesh of their respective clan-totems.
Some people firmly believe that the indestructible soul comes out of the body of the dead person and transmigrate into the totemic objects. After enjoying free-life there, the soul again takes the human form, through a miraculous conception, as a new born baby. To them, when a child is born, this is not a new life in the strict sense of the term. A spirit existing earlier in the human form has again assumed that form. It is simply one of the forefathers re-appearing in the new born.
This enlarged social unit is known as ‘Gotra’ in Sanskrit, as ‘Gotra’ in Hindi, ‘Kul’ in Bengali; the British Anthropologists call it ‘clan’ while the American Anthropologists refer it as ‘sib’. As mentioned earlier, is in paramount form among the tribals all over the globe and the ‘great-tradition’ holders, the Hindus of India.