Ötzi the Iceman, a famous Copper Age mummy who has offered insights into early European life since his discovery in 1991, now offers new clues about early human migration.
Researchers led by Frank Maixner and Albert Zink of the Institute for Mummies and the Iceman, at the European Research Academy in Bolzano, Italy, recovered DNA samples from the Iceman's gut of Helicobacter pylori (HP), a bacterium that is found in approximately half the world's human population and can occasionally cause ulcers.
The pathogen is transmitted through intimate contact and has been with humans for so long that it has become a marker for human dispersal around the world.
H. pylori in modern day Europeans is a hybrid between Asian and African bacteria. It was believed that these strains mixed together between 10,000 and 52,000 years ago. However, the researchers found that H. pylori from the Iceman is very similar to the strains from Northern India and Southern Asia, suggesting that the early human migration from Africa arrived in Europe only within the past few thousand years.
The researchers suggest that African components of the bacteria were brought in by Neolithic farmers during the last 5,000 years.
"So this HP strain, this ancient HP strain, has allowed us what is perhaps a unique opportunity to discover what populations of Helicobacter pylori existed in Europe during this copper age," Prof. Yoshan Moodley of South Africa's University of Venda, one of the study's senior authors, said in a press conference. "And when I say 'unique,' I -- this might never happen again that we find such a wonderfully preserved specimen where Helicobacter pylori DNA still can be extracted."
Past research on the Iceman -- who died on an icy mountain in the Alps after being shot with an arrow, making him one of the earliest known homicide victims -- found that he suffered from coronary heart disease and arthritis.
The study's authors agree that the conclusions are limited by having a sample size of only one, although this case can elucidate some things about the lives of ancient humans.
For example, the researchers concluded that Ötzi was suffering from a virulent strain of H. pylori when he died.
"The data tells us also ... there was an inflammatory response of the Iceman," to the infection, said the study's lead author Frank Maixner.
The image below shows a reconstruction of what researchers believe the Iceman may have looked like.