What Is Ancient DNA?
Over 30 years ago, scientists extracted the first aDNA (ancient DNA) molecules. Of course, this was only able to be done after high-throughput sequencing was invented. Genome-scale data has since been gathered from thousands of ancient archaeological specimens and a growing yet vast amount of ancient biological tissues. Ancient DNA fragments or molecules carry extensive amounts of chemical damage accumulated after death. Therefore, the process of extracting, manipulating, and authenticating are all done in controlled environments including both dry and wet laboratories. This is an important part in understanding the genetic patterns of past ancestors, species, and whole societies. Once interpreted, ancient DNA information helps address a myriad of questions for several science including anthropology, evolutionary biology, environmental and earth sciences, history, and archaeologicology.
The ancient DNA is genetic material that has been recovered from paleo and archaeological means and historical skeletal material. This can include mummified tissues, archival medical specimens, preserved plants, permafrost cores, water sediments, excavation digs. While you can learn about non-human ancient DNA from many sources including the Centre for Geogenetics, Natural History Museum of Denmark at the University of Copenhagen, this site is about ancient human DNA. By connecting to your own ancient DNA, you can breakfree from your inherited traumas and change the generational patterning you inherited.
Due to the morphological preservation in mummies, many studies up to the mid-2000s used mummified tissue as a source of ancient human DNA. Some of these samples had been preserved in ice in the Andes and also articifically preserved mummies. Yet, the majority of human aDNA studies have focused on extracting DNA from two sources – bone and teeth. The petrous bone is the most frequently used since its dense structure is good for preservation of DNA. However, a range of other tissue samples, including calcified pleura tissue embedded in paraffin and formalin-fixed tissue, paleofaeces and hair are used. Even though science and extraction methods have come so far, contamination remains a main concern. In fact, zncient pathogen DNA has been successfully retrieved from samples dating to more than 5,000 years old in humans and even longer for non-human species.
By sequencing African genomes from three Stone Age hunter gatherers that were 2000 years old, along with four Iron Age farmers that were between 300 and 500 years old, they found the earliest divergence between human populations to be 350,000 to 260,000 years ago. As of 2021, the oldest completely reconstructed human paleolithic genomes are ~ 45,000 years old. These findings have revealed a lot about the genetic insights of various countries and the interbreeding between archaic and modern humans which is like the admixture of early modern European humans and Neanderthals. Genetic and historical evidence provides an evidenciary basis that many populations mixed widely and moved or migrated vastly. Presented correctly alongside other disciplines, ancient-DNA research is a powerful weapon against racism and bigotry. Migration studies reveal that present-day people share genetic links with ancient people, often who lived in the same place and show that not many back in ancient times were 100% homogenous.
Thanks to many scientific tools and BiomedCentral, the field of ancient DNA is now a reliable research area.
WHY IS IT IMPORTANT?
Although we can read books and hear stories passed down in our family for generations, many of these turned out to be false or downright lies for various reasons. So with the data we are gathering from today's scientific tools and research, we are better apt to appreciate and revolutionize our understanding of major prehistoric and other historical events.
Because of ancient DNA, the once mysterious group of archaic humans has been discovered. We don't really know for certain what they looked like but we can learn a lot from epigenetics. For examples, the details are so refined that scientists were able to learn the fascinating changes in the larynx (aka voice box) in the development of language over the millenia. In other words, we can now correct many of the falasies of thousands of years gone by.
The ability to understand our own ancient DNA allows us to learn new facts about the lives of the ancients - our ancestors - that shaped us today.