Ancient people who lived on the mesas and in the canyons of what is now called Bears Ears, Utah, are still influencing the plant life in the area today — evidence that Indigenous ecological knowledge is essential to the future, the authors of a new study argue.

In a new paper, published Monday in the Proceedings of the National Academy of Sciences, an interdisciplinary team of researchers found that ancient sites with more architectural features still tend to have more species of plants that are important to Indigenous descendants in the area. In the researchers' multivariate model, environmental and archaeological features explained 88% of "ethnographic species richness," meaning that, where ancient people spent more time building their home, they seemed to cultivate more plants that they ate and used for medicine and ceremony.

"We knew that the flora of Bears Ears was barely known to Western science, and that management of this region, rich in cultural prehistory, would require detailed documentation," said Bruce M. Pavlik, the lead author of the study and the director of conservation at the University of Utah's Red Butte Garden. "The plant resources of Bears Ears are part of an ancient cultural heritage that has long been restricted or ignored by land management agencies."

Over a period of three years, independent teams of botanists and archaeologists looked at the frequency with which certain species appeared in places where ancient people lived, Pavlik told The Academic Times. The 25 sites the researchers surveyed spanned the agricultural formative period, dating back 1,800 to 700 years. They ranged from apparently simple hunting camps to "elaborate, multistoried cliff dwellings," Pavlik said.

The survey uncovered 31 plant species important to the Navajo, Hopi, Zuni, Ute Mountain Ute and Apache peoples that are uncommon in the landscape but concentrated around former settlements. The species they found included the Four Corners potato (Solanum jamesii), goosefoot (Chenopodium sp.), wolfberry (Lycium pallidum) and sumac (Rhus trilobata).

Native species had been overlooked by many previous researchers, while exogenous domesticates such as corn, beans and squash received much more attention. 

"There has been a particular bias towards exogenous domesticates and the rise of agriculture," Pavlik said. "We think the native plants give us insight into pre-agricultural practices, as well as uses beyond food."

Pavlik, who is white, emphasized the "essential" role that Indigenous co-authors played in shaping the study. Co-author Arnold Clifford, a Diné botanist at the Carrizo Mountain Environmental & Herbarium Inc., "brought an encyclopedic knowledge of the plants, both Western- and Navajo-based, to our attention, and the core idea of 'lifeway medicines' became a basis for developing a co-management concept for Bears Ears," Pavlik said. Diné nutritionist Cynthia Wilson of the Utah Diné Bikéyah Traditional Foods Program "helped [Clifford] transcribe Navajo names of plants onto our voucher specimens and has been involved in the issue of Bears Ears for quite some time."  

The study has implications for land management, Pavlik and his co-authors wrote: More land stewardship needs to be led by Indigenous people. 

"We are proposing a new, highly interactive form of management that allows Indigenous people to reclaim their heritage while committing to restoring the resource base," Pavlik said. "The rest of us can learn."

The study, "Plant species richness at archaeological sites suggests ecological legacy of Indigenous subsistence on the Colorado Plateau," published May 17 in PNAS, was authored by Bruce M. Pavlik, Lisbeth A. Louderback, Kenneth B. Vernon, Peter M. Yaworsky and Brian F. Codding, University of Utah; Cynthia Wilson, Utah Diné Bikéyah; and Arnold Clifford, Carrizo Mountain Environmental & Herbarium Inc.