Y-chromosomal Adam
In human genetics, Y-chromosomal Adam (Y-mrca) is the male counterpart to mitochondrial Eve: the most recent common ancestor from whom all male human Y chromosomes are presumed to be descended. Unlike other genes, those of the Y chromosome are passed exclusively from father to sons, just as mitochondrial DNA is passed to all children only by their mothers.
The Y-chromosomal Adam can also be defined as the most recent common patrilineal ancestor of all humans, considering an unbroken paternal line of descent only: fathers, paternal grandfathers, etc. Note that this is different from the most recent common ancestor traced through both paternal and maternal lines, estimated at living in earlier times.
Y-chromosomal Adam is not the same individual at all points in human history. The most recent common patrilineal ancestor of humans alive today is different from the one for humans alive a thousand years in the future: as male lines die out, a more recent individual, the Y-mrca of a subtree of the preceding Y-Adam, becomes the new Y-Adam.
The Y-chromosomal Adam for living humans probably lived between 60,000 and 90,000 years ago, judging from molecular clock and genetic marker studies. While their descendants certainly became close intimates, Y-chromosomal Adam and mitochondrial Eve are separated by thousands of generations. They are named after the "Adam" and "Eve" in Genesis as a metaphor only, and are not considered to be the first humans. There would have been many others alive at the same time.
Based on DNA analysis as of 2002, both Y-chromosomal Adam and mitochondrial Eve are believed to have lived in Africa, though approximately 85,000 years apart. This is part of the Out-of-Africa theory of human evolution.
See also
- Y chromosome
- Adam's Curse (book by Bryan Sykes)
- Genetic drift
- Genetic genealogy
- Last universal ancestor
- Mitochondrial Eve
- Molecular evolution
- Most recent common ancestor
- Y-chromosomal Aaron
References
- "Modern Men Trace Ancestry to African Migrants", A Gibbons, Volume 292, Number 5519, Issue of 11 May 2001, pp. 1051-1052.
- "African Origin of Modern Humans in East Asia: A Tale of 12,000 Y Chromosomes", Yuehai Ke et al, Science 2001 292: 1151-1153
- Fazale Rana and Ross, Hugh, Who Was Adam: A Creation Model Approach to the Origin of Man, 2005, ISBN 1-576-83577-4