Patrilineality

Patrilineality (a.k.a. agnatic kinship) is a system in which one belongs to one's father's lineage; it generally involves the inheritance of property, names or titles through the male line as well.

A patriline is a line of descent from a male ancestor to a descendant (of either sex) in which the individuals in all intervening generations are male. In a patrilineal descent system (= agnatic descent), an individual is considered to belong to the same descent group as his or her father. This is in contrast to the less common pattern of matrilineal descent.

The agnatic ancestry of an individual is that person's pure male ancestry. An agnate is one's genetic relative exclusively through males: a kinsman with whom one has a common ancestor by descent in unbroken male line.

Contrary to popular belief, one's agnate may be male or female, provided that the kinship is calculated patrilineally, i.e., only through male ancestors. Traditionally, this concept is applied in determining the names and membership of European dynasties. For instance, because Queen Victoria of the United Kingdom was married to a prince of Saxe-Coburg and Gotha, her son and successor, Edward VII, was a member of that dynasty, and is considered the first British king of the House of Saxe-Coburg-Gotha. But Victoria is reckoned to have belonged to her father's House of Hanover, despite her marriage and the fact that by marriage she legally became a member of the Saxon dynasty and acquired the surname of that family (Wettin). Agnatically, she was a Hanover, and is considered the last member of that dynasty to reign over Britain.

In medieval and later Europe, the Salic Law was purported to be the grounds for only males being able for hereditary succession to monarchies and fiefs, i.e in patrilieal or agnatic succession.

Genetic genealogy
The fact that the Y chromosome (Y-DNA) is paternally inherited enables patrilines, and agnatic kinships, of men to be traced through genetic analysis.

Y-chromosomal Adam (Y-mrca) is the patrilineal human most recent common ancestor, from whom all Y-DNA in living men is descended. Y-chromosomal Adam probably lived between 60,000 and 90,000 years ago, judging from molecular clock and genetic marker studies.

In the Bible
The line of descent for monarchs and main personalities is almost exclusively through the main male personalities. See Davidic line.