Thus, the concept of marriage is changing widely in many countries.
Historically, marriages in most societies were arranged by parents and older relatives with the goal not being love but legacy and "economic stability and political alliances", according to anthropologists.
As humans societies have evolved from hunter-gatherers into civilized societies, there have been substantial changes in relations between men and women, with perhaps one of a few remaining biological constants being that both adult women and men must have sexual intercourse for human procreation to happen.
Humans have been compared to other species in terms of sexual behavior.
However, one particularity of the human species is that pair bonds are often formed without necessarily having the intention of reproduction.
A few centuries ago, dating was sometimes described as a "courtship ritual where young women entertained gentleman callers, usually in the home, under the watchful eye of a chaperone," but increasingly, in many Western countries, it became a self-initiated activity with two young people going out as a couple in public together.Accordingly, there was little need for a temporary trial period such as dating before a permanent community-recognized union was formed between a man and a woman.While pair-bonds of varying forms were recognized by most societies as acceptable social arrangements, marriage was reserved for heterosexual pairings and had a transactional nature, where wives were in many cases a form of property being exchanged between father and husband, and who would have to serve the function of reproduction.New types of relationships formed; it was possible for people to live together without marrying and without children.Information about human sexuality grew, and with it an acceptance of all types of sexual orientations is becoming more common.