and she must*..predate the emergence of L0.

The variation of mitochondrial DNA between different people can be used to estimate the time back to a common ancestor, such as Mitochondrial Eve...

n pig heart mitochondria, phosphatidylethanolamine makes up the majority of the inner mitochondrial membrane
http://en.wikipedia.org/wiki/Inner_mitochondrial_membrane

However, acyltransferase activities involved in the reacylation of MLCL had not been identified or characterized in any mammalian tissue until 1999, by the Hatch lab at the University of Manitoba, in rat heart mitochondria.[2] In 2003, the same lab purified and characterized an MLCL acyltransferase in pig liver mitochondria,[3] and by comparing this protein against a human protein database, they identified a sequenced but uncharacterized human protein as the enzyme responsible in 2009

http://dx.doi.org/10.1074%2Fjbc.M210329200
http://en.wikipedia.org/wiki/Monolysocardiolipin_acyltransferase

This works because,..along any particular line of descent, mitochondrial DNA accumulates mutations at the rate of approximately one every 3,500 years per nucleotide.[30][31][32] A certain number of these new variants will survive into modern times and be identifiable as distinct lineages. At the same time some branches, including even very old ones, come to an end, when the last family in a distinct branch has no daughters

n a different analysis, Durbin and Li compared an X chromosome from an African with one from a non-African to determine when their ancestors stopped interbreeding after the first humans left Africa and colonized other parts of the world. Human remains and artefacts unearthed in Europe, Asia and Australia seem to suggest humans rapidly colonized these places by about 40,000 years ago, diminishing the opportunities to interbreed with Africans.

However, Durbin and Li suggest that these groups continued to interbreed until as recently as 20,000 years ago. One possible explanation, Durbin says, is that after the first humans left Africa some 60,000 years ago, successive waves of Africans followed suit, interbreeding with the ancestors of the earlier migrants.
Mix and match

Chris Stringer, a palaeoanthropologist at the Natural History Museum in London, says that human populations outside Africa were probably small and widely dispersed 20,000–50,000 years ago, so regular interbreeding with Africans seems unlikely. "There could have been surges of gene flow at particular times, driven by innovations or environmental change, but it would be surprising if these continued right through that period," he says.


Mining individual genomes can't reveal every chapter of human history, notes Reich, who now works with Li at the Broad Institute of Harvard and MIT in Cambridge, Massachusetts. The approach reveals little about upheavals of the last 20,000 years, such as the peopling of the Americas, because few chunks of the genome are young enough. Similarly, Durbin and Li's method can't deduce the history of human ancestors who existed before about 2 million years ago because few regions of the genome are much older.

http://www.nature.com/news/2011/110713/full/news.2011.413.html