Is there a role for teeth in archeology? This question might puzzle many. However, dental analysis has been used to prove many archeological evidence.
In 2018, a team of archaeologists discovered a cave in the possible dig sites of northern Laos, where they discovered several teeth that belonged to various species, including deer, pigs, and ancient relatives of modern elephants. To their surprise, a small, underdeveloped hominin tooth was also discovered, and the tooth was identified as a molar. The researchers initially hypothesized that the tooth belonged to Homo erectus, an extinct species of archaic human who existed about 2 million years ago. But the tooth is too complex to belong to Homo erectus. However, it shared little similarity with the Neanderthal, another extinct species of archaic humans who lived 40,000 years ago in Eurasia. The molar most closely resembles teeth discovered in the Denisovan jawbone from Tibet. By radiometric dating methods, it was found that the owner of the tooth lived 1,31,000 years ago. At that time, Laos would have been a mild, forested area, a contrast from the extremely cold conditions endured by Denisovans in Tibet and Siberia. According to archeologists, if the molar found in Laos belonged to a Denisovan, then it can be confirmed that Denisovans were able to adapt to a wide variety of climatic conditions.
Denisovans were first discovered in 2008, when a group of Russian archeologists visited the Denisovan cave in the Altai mountains in Siberia, Russia. They discovered a finger bone that belonged to a female juvenile hominin. The mitochondrial DNA extracted from the Denisovan girl was determined to be distinct from that of Neanderthals and modern humans.
The structuring and advancement of human societies are highly influenced by diet and analytical tools. The dietary habits of our ancestors are known to us by analysing their teeth. The most common observable condition is heavy occlusal tooth wear. Based on the evaluation of microscopic and macroscopic wear, it can be determined whether they consumed hard food or soft food. If they ate hard food, there is a good possibility that they were hunters, and if they ate soft food, chances are they were farmers.
In 2011, a study was conducted in China to evaluate the prevalence and distribution of dental caries and tooth wear in the Neolithic population of Northern China. The samples evaluated were the dental remains of 1007 permanent teeth from 79 adult individuals, which were retrieved from three Yangshao archaeological sites in the Xi'an district and surrounding states. These results suggest that the nutrition and lifestyle activities of this Neolithic population may be associated with tooth decay as well as tooth wear.
Extraction of DNA from Ancient Tooth
DNA from ancient humans and other animals is often degraded and damaged when recovered. But DNA has been successfully extracted from a variety of prehistoric organic materials, such as tissue, bone, and teeth. The sex of an individual, evolutionary development, and the presence of disease pathogens can all be ascertained using DNA retrieved from human bones and teeth. As the DNA is fragmentary, its sequence needs to be amplified using Polymerase Chain Reaction(PCR).
The thick cementum and tough enamel provide improved protection for DNA in various conditions and under certain circumstances. So, the whole tooth or tooth root is frequently used as a sample of DNA.
References:-
https://pubmed.ncbi.nlm.nih.gov/2130134/
https://www.nature.com/articles/d41586-022-01372-0
