We've heard for years that before humans developed agriculture and started living off grains and other carbohydrates, they had great teeth. That theory was formulated because of the relative lack of cavities and lost teeth in ancient fossilized skulls. That may be true, but newer DNA studies reveal that hunter-gatherers living 10,000 years ago carried around their share of oral bacteria and gum disease. These findings come from pieces of birch pitch that were used as chewing gum. These Neolithic artifacts from Scandinavia are molds of the last teeth to chew them, and they yielded DNA evidence of several kinds of bacteria that are associated with gum disease. It is estimated that 70-80% of the group studied suffered from gum disease. The pitch also gave DNA clues as to the daily diets of those people, which is quite varied. Read more about this study at Cosmos magazine, and then go brush your teeth. -via Damn Interesting
(Image credit: Verner Alexandersen)