Fingerprints are one of the few parts of the human body that generally never change — in some cases, even after thousands of years. Scientists who study ancient civilizations by way of mummified remains can attest: Mummies have fingerprints. But how?
Mummification works by drying out soft tissue such as skin, halting decomposition and preserving the body, fingerprints included. Recovering the fingertip impressions isn’t easy, but it is possible; the job requires soaking or injecting mummified hands with hydrating solutions that plump the tips. From there, the fingertips are inked and copied in a fashion similar to how modern fingerprints are recorded. 
Historians don’t just recover fingerprints from mummies — some can be found on objects, too. In fact, one set has been discovered on a 3,000-year-old coffin. Researchers at the Cambridge Fitzwilliam Museum in England discovered the prints on the internal lid of a coffin for Nespawershefyt, an Egyptian priest, in 2005; they were likely left by a craftsman who touched the lid before its varnish was fully dry. While it’s impossible to ever know the person behind the prints, historians say just seeing them helps modern people connect with people of the past.
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