Germs that made "Iceman" sick give scientists clues about ancient humans By Smithsonian.com, adapted by Newsela staff on 08.31.16 Word Count 657
TOP: Ötzi the Iceman on a sheet-covered autopsy table. MIDDLE: A portrait reconstruction of the Iceman by Thilo Parg. BOTTOM: Naturalistic reconstruction of Ötzi by Thilo Parg, Courtesy of South Tyrol Museum of Archaeology.
The legendary "Iceman" Ötzi was mummified on a glacier. He wasn't alone when he died 5,300 years ago. With him were gut bacteria known to cause some serious tummy trouble.
Learning From Bacteria These bacteria are known as H. pylori. They are providing new evidence about Ötzi's diet and poor health. They might also help scientists learn more about who his people were and how they came to live in the area. One of these scientists is Albert Zink, who studied Ötzi. He found that the bacteria in Ötzi's stomach was very strong. Today, it would give most people severe stomach diseases. Ötzi "probably had a quite severe H. pylori infection," Zink says. However, there is not enough evidence to determine how much he really suffered.
Studying The Iceman Ötzi was discovered in the 1990s in the Eastern Italian Alps. He was naturally mummified in these icy mountains after his death. The body is surprisingly well preserved. It has given scientists a huge amount of information about the Iceman's life and death. Now scientists know Ötzi's age, how he died, what he wore and what he ate. They know that he suffered from heart and gum disease, along with other illnesses. Studying the bacteria adds to knowledge about Ötzi's health problems. It also offers hints about how human populations moved into Europe. This is because H. pylori bacteria are often found in human stomachs. But not all H. pylori bacteria are the same. Over time, the bacteria grew into different strains in different parts of the world. Looking at these strains can help scientists figure out how humans first spread across the globe.
Scientist Is Surprised To study Ötzi's gut bacteria, Zink first thawed the mummy. Then he took 12 samples from it, including parts of the organs. What Zink found was a pure strain of the stomach bacteria. It's closely related to the strain found in modern Asia. However, the modern European strain of H. pylori seems to be a mix of ancient Asian and African strains. Pure African strains must have arrived in Europe only within the past few thousand years. Zink was surprised by this discovery. Scientists had thought that the pure African strain mixed with the pure Asian strain much earlier. However, Zink's study tells a different story. The results suggest that major migrations into Europe took place after Ötzi died. These movements of people brought new strains of H. pylori to Europe. Eventually, the strains mixed to become the modern European strain.
"Wild Claim" Now Appears Right More than 10 years ago, scientist Daniel Falush wrote a paper about H. pylori strains. He suggested that pure strains originally appeared in Africa, Central Asia and East Asia. Falush argued that these eventually mixed. When they did, they produced the modern strains found today. Back in 2003, scientists made this sort of "wild claim" that European H. pylori were mixed from one Asian source and one African source, Falush says. "That was thought to be quite a funny thing for bacteria at the time,” he notes. “But now they've gone back more than 5,000 years in time and found that Ötzi had bacteria that's nearly purely representative of that Central Asian strain." The prediction that later bacteria were mixed seems to be correct, he says.
"It's Far From Obvious" The question now is how the pure African strain arrived in Europe, Falush adds. “We originally guessed it was during the Neolithic migration," he says. That was around 9,000 years ago. "But it appears that was wrong." Once it arrived, the African strain must have been particularly successful. It spread right through Europe, Falush says. "But it's far from obvious why an African bacterium would spread this way. Why was it successful, and what were the patterns of contact between people?” These are exactly the kinds of mysteries scientists continue to explore. They hope future studies of the Iceman might help solve them.
Quiz 1
2
3
Based on the information in the article, which of these statements is TRUE? (A)
Modern European strains of H. pylori are usually made up of pure Asian strains.
(B)
African strains of H. pylori mixed with Asian strains about 9,000 years ago.
(C)
Özti's pure strain of H. pylori provides proof of an earlier scientist's theory.
(D)
Ötzi died from a stomach disease caused by a very strong strain H. pylori.
Which sentence from the article supports the conclusion that the recent discovery of H. pylori in Ötzi's stomach is an important scientific finding? (A)
They might also help scientists learn more about who his people were and how they came to live in the area.
(B)
They know that he suffered from heart and gum disease, along with other illnesses.
(C)
Over time, the bacteria grew into different strains in different parts of the world.
(D)
More than 10 years ago, scientist Daniel Falush wrote a paper about H. pylori strains.
Which of the following are two main ideas from the article? 1. 2. 3.
4.
Ötzi died 5,300 years ago and has since been mummified on a glacier in the Eastern Italian Alps. Scientists have discovered an unexpected strain of bacteria in Ötzi's stomach. The H. pylori from African and Asian sources are thought to be pure strains while the H. pylori from European sources have been shown to be mixed strains. The recent findings have changed scientists' understanding of human migration and raised more questions to study.
(A)
1 and 2
(B)
1 and 3
(C)
2 and 4
(D)
3 and 4
4
Which detail would be MOST important to include in a summary of the article? (A)
There is not enough evidence to know how much Ötzi suffered from the bacteria in his stomach.
(B)
There are different strains of H. pylori that come from different parts of the world.
(C)
Zink first had to thaw Ötzi's mummified body and then took 12 samples from his organs.
(D)
Ötzi's mummified body was discovered in the Eastern Italian Alps in the 1990s.
Answer Key 1
2
3
Based on the information in the article, which of these statements is TRUE? (A)
Modern European strains of H. pylori are usually made up of pure Asian strains.
(B)
African strains of H. pylori mixed with Asian strains about 9,000 years ago.
(C)
Özti's pure strain of H. pylori provides proof of an earlier scientist's theory.
(D)
Ötzi died from a stomach disease caused by a very strong strain H. pylori.
Which sentence from the article supports the conclusion that the recent discovery of H. pylori in Ötzi's stomach is an important scientific finding? (A)
They might also help scientists learn more about who his people were and how they came to live in the area.
(B)
They know that he suffered from heart and gum disease, along with other illnesses.
(C)
Over time, the bacteria grew into different strains in different parts of the world.
(D)
More than 10 years ago, scientist Daniel Falush wrote a paper about H. pylori strains.
Which of the following are two main ideas from the article? 1. 2. 3.
4.
Ötzi died 5,300 years ago and has since been mummified on a glacier in the Eastern Italian Alps. Scientists have discovered an unexpected strain of bacteria in Ötzi's stomach. The H. pylori from African and Asian sources are thought to be pure strains while the H. pylori from European sources have been shown to be mixed strains. The recent findings have changed scientists' understanding of human migration and raised more questions to study.
(A)
1 and 2
(B)
1 and 3
(C)
2 and 4
(D)
3 and 4
4
Which detail would be MOST important to include in a summary of the article? (A)
There is not enough evidence to know how much Ötzi suffered from the bacteria in his stomach.
(B)
There are different strains of H. pylori that come from different parts of the world.
(C)
Zink first had to thaw Ötzi's mummified body and then took 12 samples from his organs.
(D)
Ötzi's mummified body was discovered in the Eastern Italian Alps in the 1990s.
