Polygyny is of two types: (i) Sororal Polygyny and (ii) Non-Sororal Polygyny.
(i) Sororal Polygyny is a type of marriage in which the wives are invariably the sisters. It is often called ‘sororate’. The Latin word ‘Soror’ stands for sister. When several sisters are simultaneously, or potentially the spouses of the same man, the practice is called ‘sororate’.
It is usually observed among the tribes which pay a high bride price. The death of the wife or her childlessness is compensated by supplying a new spouse who is generally the younger sister of the deceased woman.
(ii) Non-Sororal Polygyny as the term indicates is a type of marriage in which the wives are not related as sisters. For social, economic, political and other reasons, both the types are practised by some people.
Causes of Polygyny:
Sociologists and anthropologists have made several studies to find out the causes of polygyny. Some of the factors mentioned by them are as follows:
(a) More Women less Men:
Polygyny becomes a natural practice whenever there is an excess of females over males. Even though the balance of sex-ratio is normally maintained, it is likely to be upset for some reason or the other.
Such a situation makes the members to practise either polygyny or polyandry if they want to have legitimate sex life. Plains Indians and Eskimos, for example, practise polygyny due to the imbalance in the sex-ratio.
(b) Economic Advantage:
Some of the African tribes (Ex: Longos and the Thongas) practise polygyny for economic reasons. In the tribes women contribute to the family income by various means. Sometimes the first wife compels the husband to go for second marriage so that she can reduce her load of work at home.
(c) Women as Badges of Distinction:
Among some tribals, a man’s social status is often measured in terms of the number of wives that he has. Greater the number of women greater is the prestige. Early Kings used to marry more women for this reason also.
(d) Childlessness of the First Wife:
Barrenness on the part of the first wife is also the cause of polygyny. The childless wife herself may insist on the husband to go for the second marriage.
(e) Constancy of Sex Urge in Man:
Unlike the woman, man is susceptible to sex stimulation throughout the year. Polygyny provides him opportunity to enjoy sex life throughout the year.
(f) Other Factors:
In addition to the above, the following factors also favour polygyny.
(i) Taste for variety:
Men go after several women for they have a taste for variety.
(ii) Enforced Celibacy:
Sex relations with a woman during her menstrual, pregnancy and lactation periods are tabooed. This enforced celibacy is a case in favour of polygyny.
(iii) Earlier ageing of the Female:
Among some tribes men marry more women because, they believe that ageing is faster in women.
(iv) Desire for More Children:
The desire for more children on the part of men also supports polygyny. The African ‘Guni’ and ‘Hihi’ tribals practise polygyny for this reason.
(v) Captured Women in wars and fights are normally taken and enjoyed by the victorious men as their additional wives.
(vi) Men may also marry more women to establish their masculinity.