This study investigated whether highways acted as barriers to gene flow for pronghorn in northern Arizona. DNA samples from 132 pronghorn were analyzed using eight polymorphic microsatellite loci. Samples represented animals living on opposite sides of US Route 89 (US 89) and State Route 64 (SR 64). Two different modeling approaches indicated that both US 89 and SR 64, and to a lesser extent US Route 180 (US 180), acted as barriers to gene flow. The genetic structuring caused by highways, especially across US 89, is consistent with behavioral data that demonstrated pronghorn rarely cross this highway. This study found no evidence of inbreeding or reduced genetic variation in any of the populations examined, but those effects may take longer to appear. Based on these results, the researchers recommend future genetic monitoring of these populations or assessment of genetic variation across highways with larger traffic volumes or longer histories to determine whether the barrier effects documented here lead to loss of genetic diversity.

The Arizona transportation history project was conceived in anticipation of Arizona’s centennial, which will be celebrated in 2012. Following approval of the Arizona Centennial Plan in 2007, the Arizona Department of Transportation recognized that the centennial celebration would present an opportunity to inform Arizonans of the crucial role that transportation has played in the growth and development of the state.

The report consists of a historical narrative and a series of topical essays. The seven-chapter historical narrative is a history of Arizona’s highways that extends from the pre-Columbian era to the present. The 14 topical essays extend the scope of the history beyond the state’s highway system. They include overviews of the development of other transportation modes (railroads, aviation, and urban transit), a brief history of highway pavements, a lighthearted look at the motoring experience during the 1920s and 1930s, and an exploration of how changes in transportation infrastructure affected some Arizona communities. The topical essays also provide additional historical information on bridges, urban freeways, the Interstate system, ADOT and its predecessor agencies, and famous roads such as U.S. Route 66, U.S. Route 89, the Black Canyon Highway, and the Beeline Highway.

The report also includes a timeline of transportation-related developments. This chronology not only provides an accessible overview of Arizona’s transportation history; it also places that history in a larger context by including transportation-related developments from the rest of the nation and around the world. Finally, the report contains a guide to archives in Arizona that hold significant collections of historical photographs related to the state’s transportation history, a bibliography of published historical sources related to the history of highways in Arizona, and a discussion of how the historical narrative and topical essays could be used to produce publications and media that would be made available to the public.

State trust lands are among the greatest public assets in Arizona’s portfolio. Set aside at statehood, the Arizona State Land Department manages more than 9 million acres of trust lands on behalf of 14 beneficiaries. The largest of which by far is Arizona Public Education K through 12.The mission of the Land Department is to maximize revenues from these trust lands. In FY 2005, state trust lands generated $115 million for all beneficiaries, of which $101 million was designated to support public K-12 schools.These amounts are increasing rapidly as more state trust land becomes attractive for development in Arizona’s urban areas.

The parcel discussed in this report, “Superstition Vistas,” stands out as the jewel among Arizona’s trust lands. Not only is it situated in the path of metro Phoenix growth, but it also borders thousands of acres of public land managed by the Tonto National Forest and U.S. Bureau of Land Management. Estimates of its total value run well into the billions of dollars.

"The Treasure of the Superstitions" sets the stage for a continuing dialogue about the potential for Superstition Vistas, and indeed, all of Arizona’s trust lands. We look forward to listening to and working with our beneficiaries, citizens, counties, municipalities, real estate businesses, and other interested parties to make the most of Arizona’s “treasure.”