Conserving Evolutionary Process in the Sky Islands of Northern Mexico

The mixed pine-oak woodlands of the Sierra Madre mountain chains in Mexico are a significant focus of biodiversity for North America. Harboring about a third of the world’s pine and oak species, this highelevation region is a major center of endemism for birds, reptiles, and amphibians, including several endemic bird genera such as the thick-billed (Rhynchopsitta pachyrhncha) and maroon-fronted (R. terrisi) parrot and the Sierra Madre sparrow (Xenospiza baileyi). This area was recently selected by Conservation International as an important “hotspot” – a distinction it shares with the world’s other most “biologically rich and endangered ecoregions.” This double-edged distinction is exemplified by the imperial woodpecker (Campephilus imperialis), the world’s largest woodpecker, endemic to Madrean highlands and now likely extinct.