30 November 2023
Ancient DNA reveals migrations around Fertile Crescent heartland
Published online 26 August 2022
Analysis of Neolithic human DNA suggests there were two separate migrations from the Fertile Crescent heartland into Anatolia.
Genome-wide DNA data collected from people who lived in the Fertile Crescent and surrounding areas during the Neolithic period is enabling scientists to piece together the likely population movements and genetic influences on early farmers in the region.
“We were curious to learn more about the early farmers of North Mesopotamia – the area between the Tigris and Euphrates rivers – and their connections with other population groups in the region,” says Iosif Lazaridis at Harvard University in Massachusetts, in the United States. “The DNA traces of the past are finite and will one day be obliterated by time. It is our responsibility to learn as much as possible and bequeath this knowledge to future generations.”
Lazaridis was part of a multidisciplinary study that included archaeologists, anthropologists, and bioinformatics specialists, and is the first to analyse DNA data collected from Neolithic individuals across Mesopotamia (South-eastern Turkey and Northern Iraq), Cyprus, the Zagros mountains and Armenia. The team analysed around 1.2 million single nucleotide polymorphisms and used a computer model to build up a picture of likely population movements over time.
The researchers found that, in the Pre-Pottery era, the early Mesopotamian farmers contributed much ancestry to the first farmers of Anatolia, located to the west of Mesopotamia. By the time pottery became widely used in the late Neolithic (around 7,000 years BC), the Anatolian farmers also had ancestry from the Levant.
“This suggests there were at least two distinct dispersals of farmers into Anatolia: one before pottery was invented, involving people with only Mesopotamian ancestry, and one after, which included those with both Mesopotamian and Levantine ancestry,” says Lazaridis.
The study captured a time before different populations began to mix in what is now Armenia, around 6,000 to 5,000 BC. Data from two individuals exhibited contrasting ancestries: one found at Aknashen was dominated by local ancestry, while another at Masis Blur had Mesopotamian ancestry. “We caught the diversity of the early farmers in the region just before admixture homogenized it, which is fascinating,” says Lazaridis.
Their results also suggest that early farmers in Cyprus may have originated from Anatolia, rather than the Levant.
It is important to note that these findings are not indicative of unidirectional population movements into Anatolia – they could be the result of intermixing across and between the Levant and Anatolia regions. Further research is needed to clarify this, and the team is planning to delve deeper.
Lazaridis, I. et al. Ancient DNA from Mesopotamia suggests distinct Pre-Pottery and Pottery Neolithic migrations into Anatolia. Science 377, 6609 (2022).