Editing Most recent common ancestor (section)

=== TMRCA of all living humans ===
The age of the MRCA of all living humans is unknown. It is necessarily younger than the age of either the matrilinear or the patrilinear MRCA, both of which have an estimated age of between roughly 100,000 and 200,000 years ago.<ref>{{cite journal |last1=Poznik |first1=G. David |last2=Henn |first2=Brenna M. |last3=Yee |first3=Muh-Ching |last4=Sliwerska |first4=Elzbieta |last5=Euskirchen |first5=Ghia M. |last6=Lin |first6=Alice A. |last7=Snyder |first7=Michael |last8=Quintana-Murci |first8=Lluis |last9=Kidd |first9=Jeffrey M. |last10=Underhill |first10=Peter A. |last11=Bustamante |first11=Carlos D. |title=Sequencing Y Chromosomes Resolves Discrepancy in Time to Common Ancestor of Males Versus Females |journal=Science |date=2 August 2013 |volume=341 |issue=6145 |pages=562–565 |doi=10.1126/science.1237619 |pmid=23908239 |pmc=4032117 |bibcode=2013Sci...341..562P}}</ref>

A study by mathematicians Joseph T. Chang, Douglas Rohde and Steve Olson used a theoretical model to calculate that the MRCA may have lived remarkably recently, possibly as recently as 2,000 years ago. It concludes that the MRCA of all living humans probably lived in East Asia, which would have given them key access to extremely isolated populations in Australia and the Americas. Possible locations for the MRCA include places such as the Chuckchi and Kamchatka Peninsulas that are close to Alaska, places such as Indonesia and Malaysia that are close to Australia or a place such as Taiwan or Japan that is more intermediate to Australia and the Americas. European colonization of the Americas and Australia was found by Chang to be too recent to have had a substantial impact on the age of the MRCA. In fact, if the Americas and Australia had never been discovered by Europeans, the MRCA would only be about 2.3% further back in the past than it is.<ref>{{Cite news |last=Crenson |first=Matt |date=July 2006 |title=Roots of Human Family Tree Are Shallow |url=https://www.washingtonpost.com/wp-dyn/content/article/2006/07/01/AR2006070100463.html |access-date=2024-06-30 |newspaper=The Washington Post}}</ref><ref>{{Cite web |last=Rohde |first=Douglas L. T. |date=November 11, 2003 |title=On the Common Ancestors of All Living Humans |url=https://tedlab.mit.edu/~dr/Papers/Rohde-MRCA-two.pdf |url-status=dead |archive-url=https://web.archive.org/web/20181230184319/http://tedlab.mit.edu/~dr/Papers/Rohde-MRCA-two.pdf |archive-date=2018-12-30 |access-date=2018-05-01 |website=tedlab.mit.edu}}</ref><ref>{{cite web |date=September 30, 2004 |title='Most Recent Common Ancestor' of All Living Humans Surprisingly Recent |url=https://www.sciencedaily.com/releases/2004/09/040930122428.htm |access-date=2024-06-30 |website=Science Daily}}</ref>

Note that the age of the MRCA of a population does not correspond to a [[population bottleneck]], let alone a "first couple". It rather reflects the presence of a single individual with high reproductive success in the past, whose genetic contribution has become pervasive throughout the population over time. It is also incorrect to assume that the MRCA passed all, or indeed any, genetic information to every living person. Through [[sexual reproduction]], an ancestor passes half of his or her genes to each descendant in the next generation; in the absence of [[pedigree collapse]], after just 32 generations the contribution of a single ancestor would be on the order of 2<sup>−32</sup>, a number proportional to less than a single basepair within the [[human genome]].<ref>{{cite journal |last1=Zhaxybayeva |first1=Olga |last2=Lapierre |first2=Pascal |last3=Gogarten |first3=J.Peter |title=Genome mosaicism and organismal lineages |journal=[[Trends in Genetics]] |date=May 2004 |volume=20 |issue=5 |pages=254–260 |doi=10.1016/j.tig.2004.03.009 |pmid=15109780 |quote=The Ship of Theseus paradox […] is frequently invoked to illustrate this point […]. Even moderate levels of gene transfer will make it impossible to reconstruct the genomes of early ancestors; … |citeseerx=10.1.1.530.7843}}</ref>