As for why so many different animals contributed to the materials, O'Sullivan explained, "He used what was available to him at the time."
The sheep, goat and cattle DNA reveal that these animals were related or belonged to domesticated stock.
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O'Sullivan says that "domestication began in Europe 5,000 years earlier. The haplogroups (genetic groupings) are the same as those animals associated with the origin of domestics."
This finding adds to the growing body of evidence that Ötzi, who was about 45 when he died, came from a community that included agro-pastoralists -- people who farmed and raised animals. The Iceman's last meal, which he ate one-half to two hours before his death, consisted of alpine ibex, a European wild goat. Based on fecal material extracted from his bowels, the Iceman had eaten cereal and red deer meat sometime before the ibex feast.
"His last meal was therefore not (from) the same source as his clothing," O'Sullivan said. "We did not observe red deer or ibex leather."
The goatskin leggings provide an important clue about prehistoric clothing construction, he added.
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Angela Schlumbaum of the University of Basel and colleagues previously discovered a Neolithic leather legging from the Schnidejoch mountain pass in the Swiss Alps. Analysis determined that the legging was made from the skin of a domestic goat that lived about 4,500 years ago.
Given the similarities, O'Sullivan and his colleagues suspect that early populations, at least in the Alpine region, selected particular animal species for specific attributes when making clothing.
An exception perhaps was Ötzi's coat, which was made from a combination of at least four goat and sheep hides.
"This result may indicate a haphazard stitching together of clothing based upon materials that were available to the Iceman, as ancient rudimentary leather is posited to rapidly deteriorate after manufacture," the authors wrote.
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It's clear that Ötzi was the ultimate self-made man, dressed and equipped for wilderness survival with items that he likely made himself. His gear included a stone dagger, bows and the leather quiver.
What's less certain is if his clothing held any symbolic meaning beyond its primary purpose. Prior research may again provide clues.
Maria Anna Pabst, formerly of the Medical University of Graz, has also extensively studied Ötzi, focusing more on his body. She and her team analyzed tattoos on his skin that they believe had little if anything to do with decoration or symbolism.
"We think that the Tyrolean Iceman was tattooed for therapeutic purposes," she told Discovery News, explaining that the technique was likely similar to acupuncture.
Whatever pains the possible treatment might have been trying to soothe, it did not save the Iceman from what appears to have been a painful death. Protein analysis of Ötzi's brain tissue found that he probably suffered a head injury before his demise in the Alps. He was also found to have had joint problems, heart disease, bad teeth and maybe even Lyme disease.
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