čtvrtek 1. ledna 2004

Discover Magazine - Science Story #100


Časopis Discover každý rok zveřejňuje 100 Top Science Stories, tedy Sto nejlepších vědeckých příběhů předchozího roku. Lednové číslo roku 2004 časopisu Discover zveřejnilo tyto příběhy za rok 2003. Ten rok se mimo jiné upřesnilo stáří vesmíru na 13,7 miliard let a k tomu se vztahuje i titulní strana.
A na straně 77 zveřejnilo příběh Ötzi’s Boots Were Made for Walking.


Ötzi’s Boots Were Made for Walking

So you spend five millennia shopping for comfortable shoes, and you still can’t find a pair that fit. Then this chap from the Czech Republic hikes up a mountain in a pair of bark-net, straw-stuffed, bearskin-soled boots modeled on the footwear of a 5,300-year-old frozen mummy—and he doesn’t develop a single blister. In fact, he makes the extraordinary claim that the makeshift shoes are better insulated and better cushioned than modern-day hiking boots and provide superior traction. Petr Hlavácek, a professor of shoe technology at Tomas Bata University in the Czech city of Zlín, created five pairs of shoes replicating those worn by the celebrated Stone Age ice man Ötzi on his prehistoric trek in the Ötztal Alps in northern Italy. Then he and three bold friends put the shoes on—sans socks—and retraced the ice man’s final footsteps to the glacier where his body was found in 1991, a distance of some 12 miles. Even when they stepped into icy streams, they felt no discomfort. “The shoes were full of water, but after three seconds it was a very comfortable, warm feeling,” says Hlavácek, who displayed the shoes in Offenbach, Germany, in July. “This is because the layer of hay is full of airholes, and air is the best warm insulator.” Furthermore, the linden-bark-net uppers were loose enough to even out the overall pressure of the boots, so that blisters did not form. And the bearskin soles of Ötzi’s shoes—tanned with bear brains and liver—provided an excellent grip upon the rocky mountain paths.
Ötzi may have been well shod, but that apparently did not enable him to outrun his enemies. The latest findings, announced in August, show that he stood his ground and may have fought off several foes before dying of an arrow shot to his left shoulder. Molecular archaeologist Tom Loy of the University of Queensland in Brisbane, Australia, analyzed blood from Ötzi’s arrows, knife, and coat and found DNA from four separate people—not including the ice man himself. Although their identities can never be known, the absence of an arrow shaft in his shoulder—only the arrowhead remains—suggests that one was a companion who pulled out the shaft. As for the others, they were probably rival hunters. According to Loy, Ötzi’s long, lightweight arrows indicate that he was a specialist hunter of ibex, long-horned goats that live high above the tree line; such arrows would not have worked well in the forest, where they would readily have become tangled in the branches of trees. Loy speculates that the ice man’s trade may have taken him into mountain passes whose boundaries were disputed: “He could easily have run across someone from another valley who took umbrage at finding Ötzi hunting in territory he considered his own.”
Josie Glausiusz