How was the arizona- sonoran region developed a separate identity that is is neither american nor mexican?

Shared resources.

Explanation:

The desert region covers most parts of the southwestern U.S in Arizona and California and is regarded as the hottest desert of Mexico and has an area of 260,000 km square. The western part of the Mexican border passes through this area. It's bounded by the peninsular ranges that separate it from California and the ecoregions of the pacific slope and this region forms a subpart of the colorado desert. it has maintained a separate identity due to the cross-flow of the people across the border and many people living there are bilingual and commute for work Their value system has been affected by the nearness of the different cultures. Thus it acts as a cultural buffer zone for both national and  cultivates its own identity and traditions

Italian workers migrated to northern provinces

C. naturally in the environment