1.   Already, development has eaten away at the Santa Catalina sky island outside Tucson and has begun to encroach on others farther out in the country.

2.   Isolated from similar species on other sky islands as effectively as if they were in the Galapagos, they represent especially potent raw material for evolutionary change.

3.   March though May and September through November are seasons for hiking in the sky islands.

4.   Scientists call them sky islands.

5.   So we headed for the hamlet of Portal via Pinery Canyon Road, a high altitude route that bisects the sky islands at Onion Saddle.

6.   That is too close for comfort for the Malpai ranchers, whose territory includes the Peloncillo and Animas sky islands, the next two over from the Chiricahuas.

7.   The Chiricahua Apaches were deported from their sky islands and dumped in prostrate Florida.

8.   The plateau to the north side of the Grand Canyon is a sky island that is home of perhaps the most prized mule deer herd in North America.

9.   The sky islands exist as a sort of biological Nafta, where national boundaries blur.

10.   They are called sky islands, and they are home to one of the richest panoplies of living creatures on the continent.