Race is only skin-deep

Geneticists shine new light on the Tarim Mummies of Western China and demonstrate, yet again, that modern perceptions of race are only skin-deep.

The Tarim Basin in western China is part of the Silk Road and lies where Eastern and Western cultures intersect. This has long been a major crossroads of exchanges of people and their cultures across Eurasia. Hundreds of naturally mummified burials have been discovered over the past few decades, all dating from about 2000 BC to AD 200. Their well-preserved bodies wear felted and woven woollen garments. They lie in what appear to be boat coffins, which is surprising in such an arid environment many kilometres from water. These were cattle people who herded cattle, goats, and sheep, while growing wheat, barley, and millet.

But who were they? From the start, the mummies startled experts with their ‘western’ physical features. Many scholars believed that they were descendants of migrating Yamnaya herders, Bronze Age people, who originated on the Black Sea steppes of southern Russia. Others believed that they originated among Central Asian oasis societies with strong genetic ties to early farmers on the Iranian Plateau.

An international team of researchers has now studied genome-wide data from 13 of the earliest known Tarim mummies, which date to c.2,100 to 1,700 BC, also five somewhat earlier people (c.3,000 to 2,800 BC) from the neighbouring Dzungarian Basin. The results were surprising. It now transpires that the Tarim people were far from newcomers to the region. Rather, they appear to be direct descendants of a once widespread Ice Age population that apparently disappeared as the climate warmed. This ancient population, known to geneticists as Ancient North Eurasians, survive only fractionally in the genomes of present-day populations, with the highest proportions of about 40% in Siberia and the Americas. The Tarim mummies display no signs of genetic mixing, in contrast with their neighbours, yet they were culturally cosmopolitan. They belonged in a genetic isolate that underwent a prolonged genetic bottleneck before they settled in the Tarim Basin. This is, of course, only a first step in years of exciting genetic research that lie ahead.

Here at Past Worlds we observe how this is yet more evidence that the ‘ancestors’ of a given region may bear no relation to the modern inhabitants.

Image: One of the most famous Tarim mummies: ‘The Beauty of Loulan’. She dates to around 1800 BC and was about 45 years at death. The latest genetic research is published in Nature, see www.nature.com/articles/s41586-021-04052-7