I came across research by J. H. Relethford, who in a paper published in Nature in 2008 cites Templeton's work about the different expansions of our ancestors out of their African homeland.
The Archaeological Evidence
The fossil evidence shows that H. georgicus and H. erectus lived in Eurasia roughly 1.7 million years ago, and that there were different hominins in that region since then. The remains of H. heidelbergensis, Neanderthals and Denisovans also show evolution and possibly other out of Africa events around 600 ky ago. Finally our own branch, H. sapiens left Africa possibly twice, an early, "failed" migration around 250-100 ky ago and the final move that established modern humans around the world ~60 ky ago. At least, that is the official account.
The Genetic Confirmation
What is interesting is that genetic analysis done by Templeton confirms these dates. Again, I wonder if this fit between the data in the genes and the bones and stones is real, or was somehow eased with the foreknowledge of what had to be confirmed...
Below Is what Relethford wrote, including his citation of Templeton:
"The most comprehensive of these analyses has been performed by Templeton (2005, 2007) who examined 25 DNA regions: mtDNA, Y chromosome DNA, 11 X-linked markers and 12 autosomal markers using a 6-Myr-old date for the human–chimpanzee divergence for calibration. Using a method known as nested-clade phylogeographic analysis, Templeton found that 15 of these markers showed evidence of geographic expansion. The estimated ages of range expansion vary significantly across these markers and do not fit a model of a single expansion, but instead cluster into three groups: (1) an expansion out of Africa 1.9 Myr ago (95% CI=0.99–3.10 Myr), (2) an expansion out of Africa 650 000 years ago (95% CI=390 000–970 000 years ago) and (3) an expansion out of Africa 130 000 years ago (95% CI=9600–169 000 years ago)."
These three events coincide with the H. georgicus and H. erectus, the Neanderthal, and the H. sapiens migrations! I find the confidence intervals rather large (0.9 to 3.1 million years for erectus, 390-970 ky for Neanderthals and 9.6 to 169 ky for us). Such large intervals reveal a high uncertainty in the statistical analysis.
Is this a Coincidence? or do genetics and hard archaeology agree with solid evidence?
Relethford warns that: "Given the large confidence intervals typical of coalescent analysis, this correspondence should be taken as suggestive and not conclusive, but the apparent congruence of the fossil and genetic records is interesting and deserves continued attention, particularly as data on more low-recombination DNA regions become available."
Note that word of caution about Templeton's findings. John Henry Relethford originally was a staunch supporter of the Multiregionalism theory (humans evolved in parallel in the Old World and intermingled) and rejected the initial Out of Africa theory which suggested a total replacement of other hominins by modern humans as they marched across Eurasia, wiping them out. He later shifted to a compromise theory (Mostly Out of Africa) where there was an interplay between African H. sapiens and the hominins in Eurasia. He was concerned with the fate of these Eurasian people.
Alan Templeton on the other hand adopted a rigid position against the replacement Out of Africa theory, criticizing it. His papers reflect this (see above), and he continued with another paper in 2013, and again in 2023, supporting his point of view.
Templeton wrote a very interesting critique about some statistical tools, and admixture trees, which will be the subject of a future post.
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2025by Austin Whittall ©
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