Two scientists’ trek shows how Chaco Canyon people may have carried logs

As the morning sun peeked through the trees, Roger Cram braced himself for the marathon to come. But not the way he used to run.

Kram, a physiologist at the University of Colorado Boulder, stood next to undergraduate James Wilson at the end of a rural dirt road. Each wore a nylon webbing strap over his head. Attached to the bottom of their straps—called a tumpaline—a log rests horizontally across the lower backs of both.

The pair was about to embark on a 25 km journey to repeat how ancient people of chaco canyon Timber may have been transported about 1,000 years ago (Sn: 5/17/17, By the end of the day, that’s what his successful journey suggested It would have taken only a few days for two men, who had tymplines, to carry a log to Chaco.Krem, Wilson and their colleagues report on February 22 Journal of Archaeological Science: Reports,

Located in the northwest corner of New Mexico, Chaco Canyon is home to grand structures built between 850 and 1200 AD. The multi-storied stone buildings called great houses are roofed by wooden beams about 5 meters long and 22 centimeters in diameter. The site contained at least 200,000 timbers of this size.

but wood came from forests more than 75 kilometers away ,Sn: 9/26/01, Load-pulling animals and wheels were not there at that time, and timbers were not hauled. Scientists are puzzled by how ancient people, the ancestors of modern-day Diné and Pueblo people, moved large logs.

A 1986 study suggested that The mass of each log used as a beam was 275 kg., But Cram suspected that the number might not be accurate.

In 2016, he cut down a section of a tree outside his house—ponderosa pine, the same species used in Chaco—and weighed it on his bathroom scale. He then extrapolated that a 5 meter long piece of wood would be closer to 90 kg. This revelation led to a 2022 study Recalculating the mass of Chaco Canyon wood between 85 and 140 kg,

“As soon as we knew the weight was appropriate, I wanted to move them,” says Crum.

He and Wilson proposed that the stormline could be used to transport timber. These headdresses have been found on every inhabited continent and are thought to have been in use at least as far back as 2,000 years ago. They are still widely used for carrying heavy loads, such as by professional porters in Nepal. A tourmaline is placed on the crown of the head – to be in line with the cervical spine – with the attached cargo resting on the small of the back.

While there is no evidence that the Chaco people used tumlines to haul wood, there is evidence that they used them to transport other items such as water vessels.

To see if transporting Tumpline lumber was humanly possible, Krem and Wilson trained for three months during the summer of 2020, gradually increasing their load weights and running duration. Strangers passing by could not hide their confusion.

On the final day, the pair walked 25 kilometers and carried a ponderosa pine that had been air-dried, the way the Chaco people would have prepared timber. The 60 kg log was 2.5 m long and 24 cm in diameter. The entire trek took about 10 hours, and the weight of the entire wood slowed the pace of the two a bit.

“I was glad in the end it proved feasible, and that the 132-pound log we shared was off our necks,” says Wilson, a medical student at the University of Colorado School of Medicine in Aurora. But “I never really doubted that we could do it.”