Editing Most recent common ancestor (section)

==Patrilineal and matrilineal MRCA==
{{Main|Mitochondrial Eve|Y-chromosomal Adam}}
[[File:MtDNA-MRCA-generations-Evolution.svg|thumb|left|200px|Through [[Genetic drift|random drift]] or selection, lineage will trace back to a single person. In this example over 5 generations, the colors represent extinct matrilineal lines and black the matrilineal line descended from the mt-MRCA.]]

[[Mitochondrial DNA]] (mtDNA) is nearly immune to sexual mixing, unlike the [[nuclear DNA]] whose chromosomes are shuffled and recombined in [[Mendelian inheritance]]. Mitochondrial DNA, therefore, can be used to trace [[matrilineal|matrilineal inheritance]] and to find the [[Mitochondrial Eve]] (also known as the ''African Eve''), the most recent common ancestor of all humans via the mitochondrial DNA pathway.

Likewise, [[Y chromosome]] is present as a single sex chromosome in the male individual and is passed on to male descendants without recombination. It can be used to trace [[Patrilineality|patrilineal]] inheritance and to find the [[Y-chromosomal Adam]], the most recent common ancestor of all humans via the Y-DNA pathway.

Approximate dates for Mitochondrial Eve and Y-chromosomal Adam have been established by researchers using [[genealogical DNA test]]s. Mitochondrial Eve is estimated to have lived about 200,000 years ago. A paper published in March 2013 determined that, with [[95% confidence interval|95% confidence]] and that provided there are no [[systematic error]]s in the study's data, Y-chromosomal Adam lived between 237,000 and 581,000 years ago.<ref>{{Cite journal |last1=Mendez |first1=Fernando |last2=Krahn |first2=Thomas |last3=Schrack |first3=Bonnie |last4=Krahn |first4=Astrid-Maria |last5=Veeramah |first5=Krishna |last6=Woerner |first6=August |last7=Fomine |first7=Forka Leypey Mathew |last8=Bradman |first8=Neil |last9=Thomas |first9=Mark |last10=Karafet |first10=Tatiana M. |last11=Hammer |first11=Michael F. |title=An African American paternal lineage adds an extremely ancient root to the human Y chromosome phylogenetic tree |journal=[[American Journal of Human Genetics]] |date=7 March 2013 |doi=10.1016/j.ajhg.2013.02.002 |url=http://haplogroup-a.com/Ancient-Root-AJHG2013.pdf |volume=92 |issue=3 |pages=454–59 |pmid=23453668 |pmc=3591855 |access-date=13 March 2013 |archive-date=24 September 2019 |archive-url=https://web.archive.org/web/20190924160717/http://haplogroup-a.com/Ancient-Root-AJHG2013.pdf |url-status=dead }} (primary source)</ref><ref>{{cite web|url= https://www.newscientist.com/article/dn23240-the-father-of-all-men-is-340000-years-old.html |title=The father of all men is 340,000 years old |publisher=New Scientist |date=6 March 2013 |access-date=13 March 2013 |last=Barrass |first=Colin}}</ref>

The MRCA of all humans alive today would, therefore, need to have lived more recently than either.<ref name="Ancestors_Tale">{{cite book |first=Richard |last=Dawkins |author-link=Richard Dawkins |title=The Ancestor's Tale, A Pilgrimage to the Dawn of Life |publisher=Houghton Mifflin Company |location=Boston |year=2004 |isbn=978-0-618-00583-3 |title-link=The Ancestor's Tale}}</ref>{{efn|group=note|Notions such as [[Mitochondrial Eve]] and [[Y-chromosomal Adam]] yield common ancestors that are more ancient than for all living humans.{{sfn|Hartwell|2004|p=539}}}}

It is more complicated to infer human ancestry via [[autosomal chromosome]]s. Although an autosomal chromosome contains genes that are passed down from parents to children via [[independent assortment]] from only one of the two parents, [[genetic recombination]] ([[chromosomal crossover]]) mixes genes from non-sister [[chromatids]] from both parents during [[meiosis]], thus changing the genetic composition of the chromosome.