For a long time, scientists considered Ötzi the Iceman a messenger from the Copper Age. But new research shows this frozen mummy wasn’t alone. He hosts small companions — dormant, cold-adapted yeasts. In other words, his remains might not be as frozen in time as researchers once thought.

Since Ötzi’s discovery in the Italian Alps in 1991, his body has been housed in a specialized facility in Bolzano, Italy. Scientists there held his remains at –6° Celsius (21.2° Fahrenheit). This has been to keep his body from degrading. It’s a temp close to that of the glacier in which he’d been found.

Four ancient species of yeast have now been found in his remains. And they’re still able to grow in the lab, reports Albert Zink. His team isolated “ancient DNA from these species,” he notes. An anthropologist, until recently, he worked at the Eurac research center in Bolzano, Italy. (He’s now at Ludwig Maximilian University of Munich, in Germany.)

Those DNA show the yeast “accompanied [Ötzi] over thousands of years while he was preserved in the ice,” Zink says.

Scientists suspect Ötzi thawed and refroze several times — especially in the first 1,500 years after his death. That could help explain why his remains still host microbes.

Zink’s team shared its results on June 3 in Microbiome.

Frozen in time?

Researchers thawed Ötzi’s body to 4 °C (39.2 °F) for five hours. Then, they collected the liquid that melted off his remains. They also swabbed parts of Ötzi’s body and took samples of his skin and other tissues.

Four colonies of yeast grew from these samples. Scientists compared these yeasts to those in soil near the glacier where Ötzi was found. They also checked air and the water that the museum had used to keep the mummy’s chamber humid.

These tests showed those four yeast species really came from the mummy. They were effectively time capsules of Ötzi’s time in the ice after his death. Bacteria were also extracted from internal tissues. None of these grew in the lab.

The new findings suggest the iceman’s remains seem to still be interacting with the environment.

Risks to the mummy

Those microbes could pose a problem. If they don’t stay dormant, they could end up decomposing the mummy.

This conclusion is “right on the mark,” says Patrick Hunt. He’s an alpine archaeologist at Stanford University in California who did not take part in the new study.

Ötzi is “the most important archaeological-science finding of the 20th century,” Hunt says.

Ötzi’s mummy has offered an incredible window into the man’s former life. From many studies, scientists know he wore leather clothes, had multiple tattoos and would have likely gone bald. Past work even shows he ate a high-fat meal before he died and carried an ax made of copper derived from far away.

More such discoveries may emerge only if Ötzi’s body remains preserved. That requires getting to know the cold-loving and potentially damaging microbes on his body. It also makes the new findings essential, Hunt says. They’ll help scientists preserve this iceman for the ages. 

Analysis of six mummies from ancient Egypt challenges the idea that the bows and daggers buried with some royal women were merely ceremonial.

A Maya calendar formula bears the name Sak Tahn Waax, the first known Classic Maya mathematician-astronomer directly credited for such work.

Archaeologists have discovered the remains of at least 37 people, some likely dating from more than 1,000 years ago. A large stone “jar” in northern Laos became their last resting place. Part of the mysterious “Plain of Jars,” it’s one of thousands of similar ancient stone vessels. A local legend says giants used the jars to make rice wine. Researchers now think the newfound jar was a multigenerational burial site for ancestor worship.

That would make the Plain of Jars a vast ancient burial complex. Researchers describe this in the August issue of Antiquity.

The newfound stone jar spans more than two meters (6.6 feet) across. It sits in a forest about 70 kilometers (40 miles) northeast of Phonsavan, Laos, in Southeast Asia. Part of the Xieng Khouang Plateau, this region is dotted with thousands of the stone jars.

The most well-studied groups are around Phonsavan itself. However, the entire plateau is now considered the Plain of Jars.

People had noticed a few of the jars contained bones or some ashes. But it seemed unlikely that so many large stone vessels would have been carved for burial ceremonies. So the jars’ original purpose had been a mystery.

“The big jar we’ve found is unique, and I’ve seen a lot of jars,” says Nicholas Skopal. He’s an archaeologist at James Cook University in the Queensland city of Townsville. This vessel finally confirms that the jars were part of ancient burial ceremonies, he says. But their precise use at different places may have varied.

Many sets of bones inside the newfound jar are separate. They are not part of a full skeleton. That suggests this jar is a “secondary burial” — a spot chosen for bodies that had partially decomposed elsewhere (such as in smaller jars). There are several smaller jars a short distance away.

“Maybe they used those [smaller] stone jars to ‘distill’ the bodies,” Skopal suggests. Remains might have been put in those smaller jars until “all the flesh comes off,” he says. “Then they take the bones and they put them … in this big jar. So it’s like a big crypt, almost.”

The long-standing mystery of the Plain of Jars

French archaeologist Madeleine Colani investigated the stone jars near Phonsavan in the 1930s. Most are just over a meter high (a bit more than 3 feet). Some weigh several tons. Some are lying on their side. A few had stone lids.

Early French explorers had assumed these jars once stored food and water. Colani rejected that. She instead suggested the jars had a burial role.

Scientists largely overlooked this remote region after Colani’s survey. Newer expeditions were hampered by the large number of explosives from the Vietnam War left in this area. Lao officials have been working to clear out the explosives.

Archaeological studies since the mid-1990s found burial pits filled with ancient human remains next to the jars. The remains might have been left there to decompose while awaiting later placement in the jars.

Colani had estimated that the oldest jars could have been made in the 5th century B.C. That would be up to 2,500 years ago. More recent radiocarbon dating indicates the remains are less than half that old — about 1,000 years old. Some jars contained ashes and burned bone fragments, a sign of cremations. This practice is a later, Buddhist tradition. Perhaps the jars were reused for burials after Buddhism took hold in this region, Skopal suggests.

“This is a collective mortuary assemblage,” says Miriam Stark, who did not take part in the new work. “I find that very interesting.” An anthropologist and archaeologist, Stark works at the University of Hawaii at Manoa. She says she had been hoping a jar like the newly studied one would be found.

No sign yet exists of which people might have used the jars for burials, she notes. “I do wonder, where did these people live?”

Two studies of Neandertal remains suggest their newborns were about the same size as those of modern humans but developed faster through infancy.

Plague DNA in ancient graves near Siberia's Lake Baikal suggests the disease threatened people long before farming and crowded settlements.

The cold-loving yeasts from Ötzi’s remains suggest the Iceman’s microbiome may not be completely frozen in time.