Ancient DNA: a new frontier in Caribbean archaeology
Ancient DNA is like ice cream – it does not last well in the sun. Therefore, most ancient DNA studies to date have been conducted on samples from cold or temperate environments.
Ancient DNA vs. Temperature
Freezing temperatures slow chemical reactions and inhibit microbial activity that can eat away cells and expose the fragile DNA molecules inside. Warmer temperatures on the other hand accelerate chemical reactions and the presence of water also contributes to the breakdown of molecules. Average annual temperatures in the Caribbean rarely drop below 25°C and it is often very humid.
It is no surprise, then, that very few ancient DNA studies have been conducted in the Caribbean to date, the assumption being that DNA does simply not survive long enough in this challenging environment. However, as Lizzie Wade reports in Science this week, the situation is slowly changing as ancient DNA researchers are starting to make inroads into the Caribbean.
As part of the NEXUS1492 project, Dr. Hannes Schroeder, Dr. Christina Warinner, and PhD student Kirsten Ziesemer are using ancient DNA techniques to shed new light on the demographic and health history of the Caribbean and the impact of European colonization on indigenous communities in the region.
Three Approaches to Ancient DNA
Dr. Schroeder has conducted groundbreaking ancient DNA research in the Caribbean, studying the ancestral origins of enslaved Africans, and he is now using the same techniques to explore the earlier demographic history of the region.
Dr. Warinner is a pioneer in the emerging field of ancient microbiome research, and she has teamed up with the NEXUS1492 project to explore the oral and respiratory health of the Pre-Columbian Caribbean.
Ms. Ziesemer’s research focuses primarily on dental calculus as a new source of paleogenomic data. Much of the work so far has focused on refining existing methods and developing new ones, specifically to work with extremely degraded DNA. The results are encouraging and the work is ongoing. “Ancient DNA”, says Ms. Ziesemer, “can help us crack some of the biggest questions in Caribbean archaeology, so I am very excited to be part of this project.”
by Hannes Schroeder, Tina Warinner, and Kirsten Ziesemer