A wounded—and possibly wanted—man, Ötzi the Iceman spent his final days on the move high up in the Alps until he was felled with an arrow to the back. About 5,300 years later, archaeologists are still unraveling the mystery of his death. Now, a new analysis of mossy plant remains from the Iceman’s murder site may reveal details of his frantic, final climb.
Since 1991, when hikers in the Ötztal Alps discovered his frozen, naturally mummified body near the border between Italy and Austria, researchers have counted more than 60 tattoos on Ötzi's skin and shown that he was wearing a leather coat stitched together from the hides of several sheep and goats. They recently found his lost stomach, and from its contents, learned that Ötzi was murdered just an hour after eating a final meal of dried ibex and deer meat with einkorn wheat. They've shown that the 40-something man was likely suffering from stomach pains when he died, and was nursing a seriously injured right hand, cut nearly to the bone between his thumb and index finger.
To date, scientists have also documented at least 75 types of bryophytes, a plant family that contains mosses and liverworts, in and around the mummified remains of Ötzi. Now, these humble plants are revealing the Iceman’s final moments in greater detail, while reaffirming the idea that his last days were hectic and violent.
In a new analysis published today in the journal PLOS ONE, researchers show how about 70 percent of the bryophytes found at the high-altitude Iceman site were non-local, with many of them originating at lower altitudes south of the Ötzal Alps. By working out how those botanical remains came to be deposited around Ötzi’s murder scene at the Tisen Pass—at an altitude of 10,530 feet—researchers have partially reconstructed the story of his final journey: a chaotic back-and-forth climb covering thousands of feet in altitude in a span of two days.
A mossy mystery
James Dickson, a retired professor of archaeobotany at University of Glasgow and the lead author of the new research, has been studying Ötzi since 1994 when he received samples of organic remains excavated from the site where the mummy was discovered. Dickson says he was immediately intrigued when he saw flat neckera (Neckera complanata), a moss species that historically has been used for caulking boats and log cabins.
Flat neckera was found in relatively large quantities at the site, often stuck to Ötzi's clothing. The moss may have been part of Ötzi's toolkit, though its purpose is still unclear. Was it used for insulation? Or perhaps toilet paper? In any case, the species only grows at lower altitudes; its presence helped researchers start mapping Ötzi's final journey.
"It was quite an unusual situation to find this person murdered in the Alps, at quite a high altitude," says anthropologist Albert Zink, who leads research on Ötzi at the Institute for Mummy Studies at Eurac Research in Bolzano, Italy, but was not involved in the new study. "Nobody could really explain why he was up there."
Ötzi's preserved digestive tract contained not just food but also traces of background pollen from the environment in which he ate his last meals, which provided a vague map for his final journey in previous research led by Klaus Oeggl, an archaeobotanist of Innsbruck University in Austria, who is also a co-author of the new study.
Samples from Ötzi's rectum and the lower part of his colon, representing the oldest digested food in his system, had traces of pine and spruce pollen. This put Ötzi in a high-altitude forest, close to the top of the tree line around 8,200 feet, about 33 hours before his death. But the middle tract of the Iceman’s colon contained pollen from hop hornbeams and other trees that only grow in forests at lower altitudes, meaning Ötzi must have descended to 4,000 feet or lower—perhaps reaching the bottom of a valley—9 to 12 hours before his death. According to the pollen evidence, Ötzi then ascended again and ate his last meal in a subalpine coniferous forest before climbing even higher to Tisen Pass, where he was killed.
However, it was not totally clear if Ötzi made his final descent down slopes to the south, in what is today Italy, or the north, in what is today Austria. There are only a few possible paths to Ötzi's death site in the rugged landscape.
"We really didn't know quite precisely where he went," says Oeggl.
Low-altitude plants, high-altitude places
In the new study, Dickson’s international team of scientists drew from his extensive botanical surveys of the region and mapped the distribution of all the species of mosses and liverworts that had been identified in Ötzi's digestive tract and in the sediment around the body. (The distribution of these plants in the Alps 5,000 years ago was quite similar to the distribution today.)
Around 70 percent of the bryophyte species found in and around Ötzi's high-altitude remains do not grow in the nival zone, the highest region of alpine vegetation which starts around 9,850 feet in this part of the Alps. Some of the botanical interlopers may have been transported to Ötzi's death site by the wind or by animals such as sheep and birds. But researchers claim that there were several low altitude mosses—not just flat neckera— which could only have been brought to the site by the Iceman himself. "The distance is so far that there is no other explanation," Oeggl says.
Some of the mosses found at Ötzi's death site—including flat neckera—thrive in the Schalstal, a gorge to the south in Italy, but not in any of the nearby valleys to the north. Dickson’s map therefore points to the idea that Ötzi, in his last journey, climbed down into the Schalstal before his final ascent. The Iceman may have brushed up against mosses in the gorge, stocked up on some for his supply kit, or used them to wrap his food or dress his wounds. During his descent, Ötzi might have made it as far down as the Vinschgau valley bottom, around 2,600 feet in altitude, where he may have collected a species of bogmoss, Sphagnum affine. Dickson speculates that Ötzi may have known about the bogmoss's antiseptic properties and used it to dress his deep hand wound.
The findings fit with the general picture that most of Ötzi's connections were to the south. Isotopic evidence, for example, suggests Ötzi grew up in the southern part of the Alps and lived the last few months of his life in that area, Zink says.
Similarly, Ursula Wierer, an archaeologist from the provincial department of archaeology in Florence, Italy, says that "there is lots of evidence that the Iceman lived on the southern side of the Alps and that he ascended from that side of the Alps, to the site where he died." Wierer's recent analysis of Ötzi's toolkit suggests he was caught off guard with weapons in need of repair. She says this new study, which she did not participate in, is further confirmation of the hectic nature of Ötzi's end and "shows once again the importance of the archaeobotanical studies for the reconstruction of the last days of the Iceman."
Bryophytes such as mosses and liverworts can only be studied in exceptional scenarios of preservation, such as an anaerobic bog or, in Ötzi's case, a frozen mountain pass. As such, they're "really uncommon in archeobotany," says Logan Kistler, curator of archaeobotany and archaeogenomics at the Smithsonian National Museum of Natural History. "They don't make seeds or pollen that tend to be preserved on archaeological sites. They're pretty ephemeral in the environment." The new study, Kistler adds, is "a good example of how remarkable the Ötzi site is."
"It's one of these extraordinary cases that makes life in the past real."