The new paper by Trombetta et al. reassigned 3 East Africans carrying E* to a novel lineage, of distant common ancestry with E-P147 (current "E1"). Here's the updated phylogeny. This also got me thinking about the origin of E and DE.
For those who aren't aware, there has been a long-standing debate on whether DE is African or Asian in origin. With the increasing prevalence of Y chromosome sequencing, since recently there has been improved dating of Y-DNA lineages, courtesy of YFull.
YFull estimates proto-Eurasian CT to have bifurcated 68 kya. The TMRCA of DE and CF are slightly younger, dated to ~66 kya. If we look at these founding fathers, there are some interesting patterns. The definitively Eurasian D/C/F lineages do not break apart until 48 kya, when all three undergo rapid diversification. To use an example, a mere <2 ky separate the TMRCA of F (~48 kya) from the formation of pre-IJ.
This would be a time when proto-Eurasians (similar to Ust'-Ishim?) were expanding in various directions. The fact that D/C/F don't seem to break apart into daughter lineages for nearly 20,000 years following the origin of DE/CF, most likely corresponds with the population bottleneck, which is also visible in the autosomal DNA of modern Eurasians.
The story of E is quite different. 54 kya, the ancestors of E1 and E2 had already begun to form, and 53 kya, the ancestors of E1a and E1b had already begun to split from one another. I would say these patterns support that both CF and DE made it out of Africa, where only DE survived (DE is very close in age to CT anyway), and E would later diversify.
Those who advocate an Asian origin of Y-DNA DE or E must explain why E exhibits a distinct evolutionary history from the clearly Eurasia-derived lineages. The only way out, as I see it, is to suggest that E originated and diversified in Asia, but this would create even more problems. Where in Eurasia could E diversify so early on, while the ancestors of C/D/F underwent a bottleneck in some other location, and how was E wiped out from later Eurasians?
I would be interested in hearing some other perspectives on this.


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