Spatial linguistic variation
Spatial genetic variation
Temporal linguistic variation
Temporal genetic variation
Paleolithic
Very high
High
Moderate-to-high
Moderate-to-low
Neolithic
Moderate
Moderate-to-low
Moderate
High
Bronze Age
Moderate-to-low
Low
Moderate
Moderate-to-high
Iron Age
Low
Low
Moderate-to-low
Moderate
Modern Age
Very low
Low
Low
Moderate-to-low
In the comments below I posited a scenario to explain a strange inference from a paper from a few years back, Sequencing of 50 Human Exomes Reveals Adaptation to High Altitude:
Population historical models were estimated (8) from the two-dimensional frequency spectrum of synonymous sites in the two populations. The best-fitting model suggested that the Tibetan and Han populations diverged 2750 years ago, with the Han population growing from a small initial size and the Tibetan population contracting from a large initial size (fig. S2). Migration was inferred from the Tibetan to the Han sample, with recent admixture in the opposite direction.
2,750 years would place the divergence of modern Tibetans and Chinese a few hundred years before Confucius. In fact, it would technically post-date the first historically attested Chinese writing, from the Shang dynasty. This result was pretty incredible, though one of the main authors believes it is a reasonable estimate. There are many ways you can explain this sort of divergence time, but one way which I elucidated below is rather simple. Imagine, if you will, a large set of populations which are …