Father
A father is the male parent of a child. Besides the paternal bonds of a father to his children, the father may have a parental, legal, and social relationship with the child that carries with it certain rights and obligations. An adoptive father is a male who has become the child's parent through the legal process of adoption. A biological father is the male genetic contributor to the creation of the infant, through sexual intercourse or sperm donation. A biological father may have legal obligations to a child not raised by him, such as an obligation of monetary  support. A putative father is a man whose biological relationship to a child is alleged but has not been established. A stepfather is a male who is the husband of a child's mother and they may form a family unit, but who generally does not have the legal rights and responsibilities of a parent in relation to the child. The adjective "paternal" refers to a father and comparatively to "maternal" for a mother. The verb "to father" means to procreate or to sire a child from which also derives the noun "fathering". Biological fathers determine the sex of their  child through a sperm cell which either contains an X chromosome (female), or Y chromosome (male). Related terms of endearment are "dad" ("dada", "daddy"), "baba, papa", "pappa", papasita, ("pa", "pap") and "pop". A male role model that children can look up to is sometimes referred to as a "father-figure". Paternal rights. The paternity rights of a father with regard to his children differ widely from country to country often reflecting the level of involvement and roles expected by that society. Parental leave is when a father takes time off to support his newly born or adopted baby. Paid paternity  leave first began in Sweden in 1976, and is paid in more than half of European Union countries. In the case of male same-sex couples the law often makes no provision for either one or both fathers to take paternity leave. Fathers' rights movements such as Fathers 4 Justice argue that family courts are biased against fathers. Child support is an ongoing periodic payment made by one parent to the other; it is normally paid by the parent who does not have custody. An estimated 2% of British fathers experiences paternity fraud during a non-paternity event, bringing up  a child they wrongly believe to be their biological offspring. Role of the father. In almost all cultures fathers are regarded as secondary caregivers. This perception is slowly changing with more and more fathers becoming primary caregivers, while mothers go to work, or in single parenting situations and male same-sex parenting couples. Fatherhood in the Western World. In the West, the image of the married father as the primary wage-earner is changing. The social context of fatherhood plays an important part in the well-being of men and their children. In the United States 16% of single parents  were men as of 2013. Importance of father or father-figure. Involved fathers offer developmentally specific provisions to their children and are impacted themselves by doing so. Active father figures may play a role in reducing behavior and psychological problems in young adults. An increased amount of father–child involvement may help increase a child's social stability, educational achievement, and their potential to have a solid marriage as an adult. Their children may also be more curious about the world around them and develop greater problem solving skills. Children who were raised with fathers perceive themselves to be more  cognitively and physically competent than their peers without a father. Mothers raising children together with a father reported less severe disputes with their child. The father-figure is not always a child's biological father and some children will have a biological father as well as a step- or nurturing father. When a child is conceived through sperm donation, the donor will be the "biological father" of the child. Fatherhood as legitimate identity can be dependent on domestic factors and behaviors. For example, a study of the relationship between fathers, their sons, and home computers found that the construction of  fatherhood and masculinity required that fathers display computer expertise. Determination of parenthood. Roman law defined fatherhood as "Mater semper certa; pater est quem nuptiae demonstrant" ("The [identity of the] mother is always certain; the father is whom the marriage vows indicate"). The recent emergence of accurate scientific testing, particularly DNA testing, has resulted in the family law relating to fatherhood experiencing rapid changes. History of fatherhood. Many male animals do not participate in the rearing of their young. The development of human men as creatures which are involved in their offspring's upbringing took place during the stone age. In  medieval and most of modern European history, caring for children was predominantly the domain of mothers, whereas fathers in many societies provide for the family as a whole. Since the 1950s, social scientists and feminists have increasingly challenged gender roles in Western countries, including that of the male breadwinner. Policies are increasingly targeting fatherhood as a tool of changing gender relations. Research from various societies suggest that since the middle of the 20th century fathers have become increasingly involved in the care of their children. Patricide. In early human history there have been notable instances of patricide. For example: In  more contemporary history there have also been instances of father–offspring conflicts, such as: Non-human fatherhood. For some animals, it is the fathers who take care of the young. Many species, though, display little or no paternal role in caring for offspring. The male leaves the female soon after mating and long before any offspring are born. It is the females who must do all the work of caring for the young. Finally, in some species neither the father nor the mother provides any care.