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.Communities exerted pressure on people to form pair-bonds in places such as Europe; in China, society "demanded people get married before having a sexual relationship" and many societies found that some formally recognized bond between a man and a woman was the best way of rearing and educating children as well as helping to avoid conflicts and misunderstandings regarding competition for mates.
This disability rights timeline lists events relating to advances in the civil rights of people with disabilities in the United States of America, including court decisions, the passage of legislation, activists' actions, and the founding of various organizations.
Although the disability rights movement itself began in the 1960s, advocacy for the rights of people with disabilities started much earlier and continues to the present.
Neurobiologist Robert Sapolsky constructed a reproductive spectrum with opposite poles being tournament species, in which males compete fiercely for reproductive privileges with females, and pair bond arrangements, in which a male and female will bond for life.
These species-particular behavior patterns provide a context for aspects of human reproduction, including dating.
As humans have evolved from hunter-gatherers into civilized societies and more recently into modern societies, there have been substantial changes in the relationship 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.