These scientists lugged logs on their heads to resolve Chaco Canyon mystery

The so-called “great house” in Chaco Canyon, New Mexico, may have taken decades or more to build. Most of the large complexes had four or five floors and averaged over 200 rooms, and in the largest he boasted 700 rooms. The complex also had a large circular ceremonial area called the Kiva. To build these great homes, archaeologists estimate that the Chacos required timber from about 200,000 trees, and their 16-foot-long wooden beams stretched over 70 miles. It must have been transported from mountains as far away as (110 km).

Many scientists hypothesize how the Chacoes accomplished this feat. The latest theory, according to a new paper published in the Journal of Archaeological Science: Reports, is that the Chacoans may have used simple devices called tumplines, which are still favored by Sherpas in Nepal. That’s what it means. To test that hypothesis, co-authors Roger Crumb and James Wilson spent the summer of 2020 training a tumpline to haul about 15 miles of heavy logs. “Some people even baked sourdough bread during COVID. Instead, they used their heads to carry sand and heavy logs,” said Crumb, emeritus professor of integrative physiology at the University of Colorado Boulder.

According to Crumb and his co-authors, there were no scrapes of wood preserved near the site, and the people of Chaco Canyon had no animals or even wheels to carry them. Logs must have been carried by people, probably along the wide roads that connect this world. A 1925 publication featured a photograph depicting eight of his youths from Zuni Pueblo carrying logs. On each side he has four thin cross poles at waist height with a log on top. That picture inspired many of the mechanisms proposed for transporting logs.but the crumb and others. He noted that there was no clear evidence that the residents of Zuni Pueblo shared cultural ties with those who once lived in Chaco Canyon. I feel doubtful to infer from the image,” they wrote.

Others suggest that the timber was rolled rather than transported to a construction site, perhaps bundled into small pieces for protection or carried on shoulders. Some Puebloan and Dineo oral traditions and ethnographies also do not shed much light on this issue. Pueblo His bonita timber is carried in small wagons made of small trees, with the cross-sections at each end serving as basic wheels, one account of him. However, the description does not match any known sources of timber, such as the Chusca Mountains, Zuni Mountains, San Mateo Mountains, La Plata Mountains, and Sajuan Mountains, indicating that such wagons existed, according to the authors. There is also no archaeological evidence.

Crumb has developed his own theory of how the Chacos managed the feat, starting with his recognition a few years ago that assumptions made since 1980 about the mass of typical roof beams (error) was used in one large house and at just over 275 kilograms and 600 pounds it was potentially too expensive. “We cut a foot-long piece of pine wood and weighed it on a bathroom scale,” says Crumb. “I realized he multiplied by 16 feet and ‘doesn’t add up to 275 kilograms.'”

He and Wilson, then undergraduates in biochemistry at the University of Colorado Boulder, investigated the properties of dry wood and published their conclusions last year. We estimated it to be close to a kilogram, or just over 185 pounds. This drastically changed the calculations in determining the number of people he needed to carry the timber 60 to 70 miles. They then decided to test themselves to see if the trip was possible.