Irish Bronze Age teeth reveal human diet evolution


Bacteria that cause gum disease and cavities have been found in teeth from 4,000 years ago.

Not surprisingly, without modern dental care, oral health in ancient times would not be up to today's standards.The latest research is published in the journal Molecular Biology and Evolutionhelping archaeologists track the development of dental health over thousands of years.

Both teeth analyzed belonged to the same ancient man. They were discovered in a limestone cave in Ireland and date back to the Bronze Age of the British Isles (4,500-2,800 years ago).

A cave in an Irish forest
Kirra Caves, County Limerick, Ireland. Image credit: Sam Moore and Marion Dowd/Molecular Biology and Evolution.

Because genetic material is so well preserved in teeth, the oral cavity is one of the most intensively studied aspects of the ancient human body. But obtaining complete genomes of bacteria that lived in the human mouth before the Middle Ages has proven challenging.

The study analyzed the microbiome – the collection of microorganisms that live in our bodies – found in ancient teeth.

DNA extracted from teeth includes first high-quality ancient genome Streptococcus mutans – Bacteria are the main cause of tooth decay.

lack Streptococcus mutans Bacteria in ancient mouths may indicate that bacteria in ancient human mouths had poorer conditions to survive. Previous research has shown that Streptococcus mutans Cavities have been present in dental remains since the beginning of grain agriculture, but around 1500 AD, at the same time as sugar consumption increased, cavities became more common.

communication

“We were very surprised to see such a large number of amoeba “This tooth is 4,000 years old,” said senior author Lara Cassidy, an assistant professor at Trinity College Dublin. “This is a very rare find and shows that this person had a lot of history before death. High risk of tooth decay.”

another reason Streptococcus mutans It may be rare in ancient records because the acid it produces can break down DNA.Because the caves at Killala, County Limerick, provided a cool, dry and alkaline environment, it may have aided in preservation Streptococcus mutans.

But other teeth found at the site did not have the same prevalence of cavity-causing bacteria. This shows that the individual's microbiome is dysbiosis – Streptococcus mutans Competes with other bacterial species, leading to a pre-disease state.

This supports the “lost microbiome” theory, which suggests that our ancestors' microbiomes were more diverse than they are today.

2 genomes have also been extracted from Irish teeth that show a high degree of diversity in bacterial strains associated with gum disease, Tanella forsythia.Over the past 750 years, a Forsythia has taken a dominant position globally.

Buy Universe Print Magazine





Source link

Leave a Reply

Your email address will not be published. Required fields are marked *