An ancestor, also known as a forefather, fore-elder or a forebear, is a
parent or (
recursively) the parent of an antecedent (i.e., a
grandparent
Grandparents, individually known as grandmother and grandfather, are the parents of a person's father or mother – paternal or maternal. Every sexually-reproducing living organism who is not a genetic chimera has a maximum of four geneti ...
,
great-grandparent, great-great-grandparent and so forth). ''Ancestor'' is "any person from whom one is descended. In law, the person from whom an estate has been inherited."
Two individuals have a
genetic relationship if one is the ancestor of the other or if they share a common ancestor. In
evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
ary theory, species which share an evolutionary ancestor are said to be of
common descent
Common descent is a concept in evolutionary biology applicable when one species is the ancestor of two or more species later in time. All living beings are in fact descendants of a unique ancestor commonly referred to as the last universal com ...
. However, this concept of ancestry does not apply to some
bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...
and other organisms capable of
horizontal gene transfer
Horizontal gene transfer (HGT) or lateral gene transfer (LGT) is the movement of genetic material between unicellular and/or multicellular organisms other than by the ("vertical") transmission of DNA from parent to offspring (reproduction). H ...
. Some research suggests that the average person has twice as many female ancestors as male ancestors. This might have been due to the past prevalence of polygynous relations and female
hypergamy
Hypergamy (colloquially referred to as "marrying up") is a term used in social science for the act or practice of a person marrying a spouse of higher caste or social status than themselves.
The antonym "hypogamy" refers to the inverse: marryin ...
.
Assuming that all of an individual's ancestors are otherwise unrelated to each other, that individual has 2
''n'' ancestors in the ''n''th generation before her/him and a total of 2
''g''+1 − 2 ancestors in the ''g'' generations before him/her. In practice, however, it is clear that most ancestors of humans (and any other species) are multiply related (see
pedigree collapse
In genealogy, pedigree collapse describes how reproduction between two individuals who share an ancestor causes the number of distinct ancestors in the family tree of their offspring to be smaller than it could otherwise be. Robert C. Gunderson ...
). Consider ''n'' = 40: the human species is more than 40 generations old, yet the number 2
40, approximately 10
12 or one trillion, dwarfs the
number of humans who have ever lived
This article lists current estimates of the world population in history. In summary, estimates for the progression of world population since the Late Middle Ages are in the following ranges:
Estimates for pre-modern times are necessarily fraug ...
.
Some cultures confer reverence to ancestors, both living and dead; in contrast, some more youth-oriented cultural contexts display less veneration of elders. In other cultural contexts, some people seek
providence
Providence often refers to:
* Providentia, the divine personification of foresight in ancient Roman religion
* Divine providence, divinely ordained events and outcomes in Christianity
* Providence, Rhode Island, the capital of Rhode Island in the ...
from their deceased ancestors; this practice is sometimes known as ''
ancestor worship
The veneration of the dead, including one's ancestors, is based on love and respect for the deceased. In some cultures, it is related to beliefs that the dead have a continued existence, and may possess the ability to influence the fortune of t ...
'' or, more accurately, ''
ancestor veneration
The veneration of the dead, including one's ancestors, is based on love and respect for the deceased. In some cultures, it is related to beliefs that the dead have a continued existence, and may possess the ability to influence the fortune of t ...
''.
See also
*
Archaic humans
A number of varieties of '' Homo'' are grouped into the broad category of archaic humans in the period that precedes and is contemporary to the emergence of the earliest early modern humans (''Homo sapiens'') around 300 ka. Omo-Kibish I (Omo I) f ...
*
Collateral descendant
A lineal descendant, in legal usage, is a blood relative in the direct line of descent – the children, grandchildren, great-grandchildren, etc. of a person. In a legal procedure sense, lineal descent refers to the acquisition of estate by i ...
*
Consanguinity
Consanguinity ("blood relation", from Latin '' consanguinitas'') is the characteristic of having a kinship with another person (being descended from a common ancestor).
Many jurisdictions have laws prohibiting people who are related by blood fr ...
*
DNA
**
Lysosomal DNA
A lysosome () is a membrane-bound organelle found in many animal cells. They are spherical vesicles that contain hydrolytic enzymes that can break down many kinds of biomolecules. A lysosome has a specific composition, of both its membrane pro ...
**
Mitochondrial DNA
Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial D ...
*
Ethnic group
An ethnic group or an ethnicity is a grouping of people who identify with each other on the basis of shared attributes that distinguish them from other groups. Those attributes can include common sets of traditions, ancestry, language, history, ...
*
Family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
*
Genealogy
Genealogy () is the study of families, family history, and the tracing of their lineages. Genealogists use oral interviews, historical records, genetic analysis, and other records to obtain information about a family and to demonstrate kin ...
*
Genetic genealogy
Genetic genealogy is the use of genealogical DNA tests, i.e., DNA profiling and DNA testing, in combination with traditional genealogical methods, to infer genetic relationships between individuals. This application of genetics came to be used ...
*
Kinship
In anthropology, kinship is the web of social relationships that form an important part of the lives of all humans in all societies, although its exact meanings even within this discipline are often debated. Anthropologist Robin Fox says that ...
*
Lineage (anthropology)
A lineage is a unilineal descent group that can demonstrate their common descent from a known apical ancestor. Unilineal lineages can be matrilineal or patrilineal, depending on whether they are traced through mothers or fathers, respectively. ...
*
Lineal descendant
A lineal descendant, in legal usage, is a blood relative in the direct line of descent – the children, grandchildren, great-grandchildren, etc. of a person. In a legal procedure sense, lineal descent refers to the acquisition of estate by in ...
*
Most recent common ancestor
In biology and genetic genealogy, the most recent common ancestor (MRCA), also known as the last common ancestor (LCA) or concestor, of a set of organisms is the most recent individual from which all the organisms of the set are descended. The ...
*
Progenitor
In genealogy, the progenitor (rarer: primogenitor; german: Stammvater or ''Ahnherr'') is the – sometimes legendary – founder of a family, line of descent, clan or tribe, noble house, or ethnic group..
Ebenda''Ahnherr:''"Stammvater eines ...
Citations
External links
United States Census Bureau
{{Authority control
Kinship and descent