-“Sky Islands” are isolated mountain ranges in southeastern Arizona and northern Mexico
-Some of the mountains rise more than 6,000 feet above the surrounding desert floor making the lowlands and high peaks drastically different
-Plants and animals living in the mountains could never survive in the surrounding deserts ... thus by analogy, the mountains are “islands” surrounded by deserts that are “seas”
-One of the most readily accessible is at the end of the Mount Lemmon Scenic Byway at the top of the Santa Catalina Mountains