World's oldest ice skates was made by Finns

Ice-skating—the oldest human-powered means of transportation—was invented in Finland not for fun but for survival, according to a new study. Skates made from animal bones have been found throughout Scandinavia and Russia, including some that date back to around 3000 B.C. The wide dispersal of the ancient artifacts has made it difficult for archaeologists to pin down exactly when and where ice-skating first developed. Now scientists from Italy and the United Kingdom have calculated that people living in what is now southern Finland would have benefited the most from skating on the crude blades. The researchers showed that people traveling across the region's frozen lakes reduced their physical energy cost by 10 percent. By contrast, skaters in other northern European countries would have had only a one percent energy reduction.

"People developed this ingenious locomotion tool in order to travel more quickly and by using not as much energy as if they had walked around all the lakes," said study co-author Federico Formenti of the University of Oxford in England. The study appears in this month's issue of the Biological Journal of the Linnean Society of London.

Leather Straps

Southern Finland has more lakes within 40 square miles (about 100 square kilometers) than any other region in the world. "I think ice-skating happened in [this] area because of the several long and thin lakes that people had to cross in order to get around, hunting for food or for any daily activity," Formenti said. "Those lakes froze during the long winters, when sunlight was there only for a few hours per day."

The earliest skates were made mostly of horse bones, but other bones were also used depending on the animals available, Formenti said. Holes carved in the ends of the bones were likely strung with leather straps tied around the skaters' feet. Woodcuts from the 1500s show bone skates being used together with a stick, which was pushed between the legs to help the user pick up speed. To study the energy efficiency of this early ice-skating, Formenti's team tested replicas of bone skates at an ice rink in the Italian Alps. The researchers measured five skaters' heart rates, oxygen intake, and speed while maneuvering on the blades. The skates took some time to get used to, Formenti said, but "once you get the movement pattern, they glide really well."

"The oily external surface of the animal bones makes a natural wax which limits resistance to motion."

The team then constructed mathematical models and computer simulations of energy use for 240 6-mile (10-kilometer) skating trips across different parts of northern Europe. "This research suggests that ancient Finland would have been the most practical birthplace of the now popular winter sport," the authors write in their paper. Other studies by the same scientists have shown how fast and how far people could skate at various times in history, as bone blades gave way to iron and then to steel. The earliest skaters were probably not fast. The people testing the bone skates for the latest study reached an average speed of about 5 miles (8 kilometers) an hour. Modern speed skaters, on the other hand, can reach speeds of up to 37 miles (60 kilometers) an hour.

Skates and Skis

Steven Vogel is a biology professor at Duke University in Durham, North Carolina, who was not involved in the study. The skating research is "especially important, because just about no one else does this kind of thing—showing how biomechanical work can reveal things about history, prehistory, and anthropology," Vogel said. Like with ice skates, other modes of transportation probably developed as people searched for more efficient ways of getting around, Formenti added. "Cross-country skis … seem to have developed in Scandinavia at about the same time as bone skates," he said. "In Scandinavia there were heavy snowfalls, and skis allowed people to move around the woods without sinking in the snow with bare feet." Long, flat skis redistribute the wearer's weight, lessening the depth of each step, while heat from friction melts a thin layer of snow underneath, allowing the wearer to glide over the terrain. "The origins of skis and skates as passive tools enhancing human-powered locomotion share common roots, probably small wooden plates," Formenti said. "These became longer and wider skis on snow or shorter and thinner plates—and, for sure, animal bones—used to glide on ice."

Elite graves found in Mexico City

A structure believed to be an 800-year-old Aztec pyramid has been discovered in central Mexico City and could drastically revise the early history of the ancient empire, officials announced. The structure was found inside a larger pyramid known as the Grand Temple at the site of the Aztec city of Tlatelolco.

If the age of the edifice is confirmed, the discovery could push back the age of Tlatelolco—as well as that of its nearby "twin city" Tenochtitlán—by a century or more, said Salvador Guilliem of Mexico's National Institute of Anthropology and History. Guilliem, who is leading an archaeological effort to study Tlatelolco, said the structure's construction suggests it could have been built as early as A.D. 1100 or 1200, at least a century earlier than historical accounts suggest the city was founded. While Guilliem's team continues to work on determining the new pyramid's age, the researchers have already uncovered new insights into the Grand Temple.

"Until now we thought Tlatelolco's Grand Temple had seven phases of construction," Guilliem told National Geographic News. "Now we know that there are eight." The team also used ground-penetrating radar to locate a series of other structures near the Grand Temple containing human remains and grave offerings. "We dug 2 meters [6.5 feet] and found an offering of green stones and five skulls," Guilliem said. The remains—belonging to four adults and a child—appear to have been positioned with heads turned toward the north and bodies to the south, he added. "We will explore more next season, but we think this building corresponds to the military elite," he said. Modern interpretations of Aztec legends say Tlatelolco was built around A.D. 1358, the same year as Tenochtitlán, although archaeological evidence has cast doubt on that date in recent years, experts say.

"If true, the date of this pyramid fits with many other archaeological finds that reveal evidence of Aztec occupation earlier than the traditional dates," said Susan Gillespie, a University of Florida anthropologist. The find could also shed light on the poorly understood early relationship between Tlatelolco—a massive market province—and Tenochtitlán, the Aztec capital and one of Mesoamerica's largest cities. "The nature of Tlatelolco and Tenochtitlán's entwined origins and histories remains one of the underexplored mysteries of the Aztec era," Gillespie said. The new discovery could challenge the notion that Tenochtitlán was the dominant twin during the early, entangled development of the two Aztec provinces, said Michael Smith, an Aztec expert at Arizona State University.

"There are vague traces in the historical sources that Tlatelolco may have been more powerful than Tenochtitlán in its early decades," he said. "If there was indeed a large pyramid in Tlatelolco in the Early Aztec period, given that no such find exists in Tenochtitlán, it may suggest that Tlatelolco was indeed the dominant city in their early years. That would be significant."

What's Inside the Pyramid?

Guilliem and his colleagues believe that an offering to Tezcatlipoca Black, the Aztec god of commerce, will be found inside the newly discovered pyramid. Guilliem theorizes that workers intentionally broke into the smaller pyramid in 1368 while building a subsequent phase. "When they broke it, it is very probable that they deposited a deity that's likely to be Tezcatlipoca," he said. "They most likely deposited an offering to the deity [Tezcatlipoca Black], conducted a ceremony, [and] then closed it again." The team also wants to determine if the Grand Temple at Tenochtitlán has a similar stage of construction—a key to untangling the early power balance between the two city-states, Guilliem said Gillespie, the University of Florida anthropologist, said such a comparison could yield crucial clues to the dynamics of the ancient Aztec cities. "The great temple at Tenochtitlán similarly had many cached offerings as part of the different building phases," Gillespie said. "It will be interesting to see how the Tlatelolcan corpus of offerings compares to that of Tenochtitlán."