Hunter-gathers suffered from nearly no cases of malocclusion – crooked teeth – or dental crowding, and these conditions only became common among the world’s earliest farmers nearly 12,000 years ago in Southwest Asia, states the findings of a study published in the journal PLOS ONE.
By analyzing the lower jaws and dimensions of teeth crowns of 292 archeological skeletons from Europe, Anatolia and the Levant between 28,000 and 6,000 years ago, a team of international researchers discovered a distinct separation between European hunter-gathers, European farmers and Near Eastern/Anatolian semi-sedentary hunter-gathers, based on the structure and form of their jawbones.
“Our analysis shows that the lower jaws of the world’s earliest farmers in the Levant, are not simply smaller versions of those of the predecessor hunter-gathers, but that the lower jaw underwent a complex series of shape changes commensurate with the transition to agriculture,” states Professor Ron Pinhasi from the School of Archeology and Earth Institute, University College Dublin, and lead author on the study.
“Our findings show that the hunter-gatherer populations have an almost ‘perfect harmony’ between their lower jaws and teeth,” explained Professor Pinhasi. “But this harmony begins to fade when you examine the lower jaws and the teeth of the earliest farmers.”
Link May Be Due to Diet
In relation to hunter-gathers, researchers from the State University of New York, Buffalo, University College Dublin, and Israel Antiquity Authority found a correlation between dental distances and inter-individuals jawbones, which suggests to researchers a near “perfect” state of equilibrium between the two. While in instances of farming groups and semi-sedentary hunger-gathers, researchers found no such correlation, which suggests that the harmony between the jawbone and teeth was disrupted with the shift toward sedentism and agricultural practices in the region. This, researchers claim, may also link to the dietary changes that occurred to the different population groups in the region.
Hard Foods and Small Spaces
Hunter-gather diets were based primarily on “hard” foods like uncooked meats and vegetables, while the primary diet of sedentary farmers was focused around “soft” cooked or processed foods like legumes and cereals. With soft cooked foods there is less need to chew which in turn decreases the size of the jaws but without a corresponding reduction in the dimension of the teeth, resulting in a lack of adequate space in the jaw which in turn leads to the development of dental crowding and malocclusion.
The link between diet, chewing and related dental wear patterns has been well established in scientific study. Today, malocclusion and dental crowding impacts nearly one out of five individuals living in modern-world populations. The condition is often referred to as the “malady of civilization.”