Curated OER
Petroglyphs
Petroglyphs and pictographs are compared in these simple slides. Some of the terms are very specific, but the basic information will be useful to accompany a lecture about this visual art form. Images and real examples would have ben a...
Palomar Community College District
Wayne's World: Desert Varnish and Lichen Crust
Lichens thrive in common and in very specialized and inhospitable climates. This clickable index site offers text and photographs of desert and mountain lichens.