A preserved corpse from the Bronze Age continues to harbor living microorganisms more than five millennia after death, according to groundbreaking research published in the journal Microbiome. The mummy, known as Ötzi the Iceman, was discovered by hikers in an Alpine glacier in 1991 and has become one of the most studied prehistoric human remains in scientific history. Scientists at Eurac Research have now identified a complex ecosystem of ancient and modern bacteria and yeasts thriving within the frozen tissue, offering unprecedented insight into the microbial world of early humans.
Ötzi died around 3300 B.C., making his remains older than both Stonehenge and the Egyptian pyramids. He was between 25 and 35 years old at the time of his death and measured approximately 5 feet 2 inches in height. Initial theories suggested he perished from exposure or exhaustion while traversing the mountains, but later investigations revealed an arrowhead embedded in his left shoulder, indicating he likely died from blood loss following an attack.
Cold-adapted yeasts colonized the body after death
Research teams at the South Tyrol Museum of Archaeology in Bolzano, Italy, analyzed ice formations on the mummy’s surface, meltwater from inside the remains, and tissue samples using advanced genetic sequencing. The investigation revealed the presence of yeast species specifically adapted to frigid environments, likely originating from the glacial surroundings where Ötzi was entombed naturally. These microorganisms have persisted on the body from the time of his death through to the present day.
Scientists distinguished between microbes that existed during Ötzi’s lifetime and those that colonized his corpse post-mortem by cross-referencing tissue samples, surface swabs, and genetic markers. The team also incorporated data from previous studies examining intestinal tissue and stomach contents to build a comprehensive picture of the mummy’s microbial profile.
Gut bacteria differ significantly from modern human microbiomes
One of the most remarkable findings involves the gut bacteria preserved in Ötzi’s digestive system. Researchers identified bacterial strains not commonly found in the intestines of contemporary humans, suggesting significant shifts in human microbial communities over the past 5,000 years. This discovery provides a rare window into humanity’s microbial past, according to Eurac Research.
- Ancient gut bacteria species no longer prevalent in modern populations
- Genetic traces of microorganisms from Ötzi’s lifetime still detectable
- Glacial yeasts that survived freezing conditions for millennia
- Microbes potentially existing in dormant states within the preserved tissue
The preserved bacterial communities could help scientists understand how human diet, environment, and lifestyle changes have shaped our internal ecosystems. Some of these microbes may still exist in a dormant state more than 5,000 years after Ötzi’s death, as his body remains in carefully controlled conditions at the South Tyrol Museum.
Museum maintains strict conservation protocols for preservation
Elisabeth Vallazza, director of the South Tyrol Museum of Archaeology, emphasized that the mummy’s preservation condition remains very stable under current conservation methods. Close microbiological monitoring ensures that the remains suffer no damage from environmental factors or microbial activity, she stated. However, Vallazza acknowledged that further research and comprehensive conservation efforts are necessary to preserve the mummy for many more generations.
Conservation expert Marco Samadelli, a co-author of the study, noted that the exact conditions allowing these microorganisms to survive and interact within the frozen remains are not yet fully understood. This research expands scientific knowledge in this area, he explained, but significant questions remain about the mechanisms of long-term microbial survival in frozen human tissue.
Mummy represents dynamic biological system, not static artifact
Frank Maixner, director of the Institute for Mummy Studies at Eurac Research, described the discovery as evidence of continuous microbial presence on the mummy throughout its extensive history. The yeasts have accompanied Ötzi on his long journey through the millennia, Maixner stated. Rather than being a static relic, Ötzi functions as a dynamic biological system, he added, challenging traditional assumptions about preserved ancient remains.
The findings contribute to expanding research on mummies and ancient human remains worldwide. Earlier in 2025, officials announced that researchers from the University of Barcelona discovered a copy of Homer’s “Iliad” placed atop a mummy in Egypt. Last year, utility workers in Lima, Peru, uncovered a millennia-old mummy while performing routine maintenance work. These discoveries collectively advance scientific understanding of ancient preservation methods and the biological processes that occur in naturally mummified human remains over thousands of years.
