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WonderBiomolecular archaeology fact

Dental calculus, the hard tartar that builds up on teeth, can trap DNA, proteins, microbes and tiny food remains for thousands of years, giving archaeologists evidence of ancient diets and health.

Calculus (dental)

ArchaeologyHealthBiology

The story behind the card

Plaque hardens into calculus while a person is alive, sealing in traces of whatever passes through the mouth, and it survives in the ground far better than most soft remains. In 2017 a team studying DNA in the calculus of Neanderthals from El Sidrón cave in Spain found, in a young individual with a painful dental abscess, traces of poplar, a natural source of salicylic acid, the painkiller related to aspirin, and of Penicillium mould. The researchers suggested he may have been treating himself, though that remains a hypothesis. In 2014 a team led by Christina Warinner identified a milk protein preserved in calculus from ancient teeth, direct evidence of who drank milk as dairying spread through prehistoric populations.

Türkçe oku
Dişlerde biriken sert tabaka, yani diş taşı, DNA'yı, proteinleri, mikropları ve minik yiyecek kalıntılarını binlerce yıl saklayabilir. Arkeologlar böylece eski insanların ne yediğini ve sağlık durumunu öğrenebilir.

Diş plağı, insan hayattayken sertleşip diş taşına dönüşür ve ağızdan geçen her şeyin izlerini içine hapseder; toprakta da yumuşak kalıntıların çoğundan çok daha iyi korunur. 2017'de İspanya'daki El Sidrón Mağarası'nda bulunan Neandertallerin diş taşındaki DNA'yı inceleyen bir ekip, ağrılı bir diş apsesi olan genç bir bireyde kavak izlerine rastladı. Kavak, aspirinin akrabası olan ağrı kesici salisilik asidin doğal bir kaynağıdır; aynı dişlerde Penicillium küfünün izleri de vardı. Araştırmacılar, bu kişinin kendini tedavi etmiş olabileceğini öne sürdü, ama bu bir varsayım olarak kalıyor. 2014'te Christina Warinner'in yönettiği bir ekip ise eski dişlerin diş taşında korunmuş bir süt proteini buldu. Bu, hayvancılık tarih öncesi topluluklara yayılırken kimlerin süt içtiğinin doğrudan kanıtıdır.

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Background reading: Calculus (dental)
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