- News Home
27 November 2013 12:59 pm ,
Vol. 342 ,
The new head of the National Center for Science Education promises to "fight the good fight" against attacks on...
Analyses of the H7N9 strains isolated from four new cases show that the virus is evolving rapidly, heightening anxiety...
In 2009, Jack Szostak shared a Nobel Prize for his part in discovering the role of telomeres, the end bits of...
Science has exposed a thriving academic black market in China involving shady agencies, corrupt scientists, and...
Paper-selling agencies flourish in the aura of reputable businesses. For some scientists, it may be difficult to tell...
Featuring the first lunar rover in 40 years, Chang'e-3 is seen as an important milestone on China's quest to send a...
Data collected by satellites and floating probes have chronicled a 2-decade rise in the temperature and thickness of a...
Cholesterol, the artery-clogging molecule that contributes to cardiovascular disease, has another nasty trick up its...
- 27 November 2013 12:59 pm , Vol. 342 , #6162
- About Us
Building an Ancient City
24 September 2001 7:00 pm
A thousand years ago a Native American people, the Anasazi, hauled more than 200,000 pieces of timber from distant mountains to build a city deep in the New Mexico desert. Now, archaeologists are finding that the choice of wood used in the Anasazi dwellings could provide valuable clues about the society. The timber came from two surrounding mountain ranges and not a third equidistant range, suggesting that economic and cultural ties probably dictated the choice of timber sources.
The Anasazi culture dominated what is now New Mexico beginning around 550 A.D. Then, about 850 years ago, the civilization abruptly disappeared, probably because the people dispersed during a prolonged drought. Today the Chaco Canyon remains include 12 wood and sandstone houses, or pueblos. But with three mountain ranges equidistant from the site, the provenance of this lumber has long puzzled archeologists. Some suggest that the Anasazi logged different ranges after exhausting suitable trees from each area, while others argue that their choice of logging site indicates cultural and economic ties with neighboring peoples.
To examine this issue, geochemist Nathan English and his colleagues at the University of Arizona in Tucson compared the chemistry of 52 logs in Chaco's walls with that of 200 log, rock, and water samples in the three ranges. In particular, they measured levels of a rare metal called strontium that has two forms, or isotopes, present in different ratios at different locations. In the 25 September online edition of the Proceedings of the National Academy of Sciences, English's group reports that the lumber came from two ranges--San Mateo and Chuska--that were logged simultaneously. The third mountain range was never touched. These preferences suggest to the researchers that ties to nearby communities determined where the Anasazi logged.
The study not only sheds new light on the wider economic system to which Chaco belonged, but is also a "pioneering" effort to use strontium isotopes to track the origin of botanical remains, says archaeologist Jeremy Sabloff at the University of Pennsylvania Museum in Philadelphia. The researchers are hoping that the new technique will clarify the origin of corn husks and turkey bones at the Chaco canyon.