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They say dead men tell no tales. If that was ever true, it is certainly not so now in our scientific era. Case in point: ¿tzi, the 5,000-year-old "Iceman" mummy discovered in 1991 by two hikers high in the Alps along the Austrian-Italian border. Affectionately nicknamed for the ¿tzal region in which he was found, ¿tzi has been subjected to waves of scientific tests in an attempt to reconstruct his life and death. Now, according to a report published today in the journal Science, researchers have amassed evidence suggesting that ¿tzi, believed to be in his mid-40s when he died, may have spent his whole life in what is now Italy, within about 60 kilometers of where he was found.
By investigating the isotope compositions of minerals found in Ozti¿s tooth enamel, bones and intestine, and comparing them to those of environmental sources like water and rocks, the researchers were able to identify particular areas near where ¿tzi died as places he probably frequented. Oxygen isotopes, for example, hint at where ¿tzi got his drinking water. Levels of these isotopes in his tooth enamel, which is fixed during childhood, suggest that ¿tzi spent his early years in lower elevations south of where his body turned up. Levels in his bones, which remineralize throughout life, indicate that the Iceman ventured into higher altitudes during later years.
Strontium isotopes in teeth and bones narrowed the geographical possibilities even further, pointing to areas of distinct rock composition. And data from argon isotopes from very small rocks in ¿tzi¿s intestine--presumably ingested with food or water--fine-tuned the picture. Geochemist Wolfgang M¿ller of the Australian National University in Canberra, the lead author on the study, says he and his colleagues were able to select one locality in the area with the closest isotopic matches between ¿tzi and the environment as a possible site of ¿tzi¿s childhood. Called Feldthurns, this site in the Eisack Valley has produced archaeological finds typical of the Copper Age, the period during which ¿tzi lived. The argon data suggest that he subsequently spent time in the Etsch Valley, before heading to the ¿tzal region where he died. But other nearby sites are geochemically consistent with data from ¿tzi, too, M¿ller points out. "I would talk of probabilities and likelihoods," he says, "you can¿t say for certain."
Part of the mystery surrounding ¿tzi¿s life comes from the fact that he seems to have been far from home when he died. Discovered high up in the snowy mountains, dressed against the cold and possibly bearing injuries related to a fight, the Iceman¿s corpse raises tantalizing questions about just what ¿tzi was doing there. But M¿ller says that the location at which ¿tzi was found is compatible with the travels of a shepherd of the time, noting that the data indicate that ¿tzi spent one or two months a year at high altitudes. --Chris Jozefowicz
