Inaki Relanzon / Baroque altar piece in Nativity of Durro Church, romanesque church from XII century, and UNESCO world heritage, in the Boí Valley, Pyrenees, Lleida, Catalonia, Spain.July 2009

Jack Dykinga / Teddy bear cholla cactus {Opuntia bigelovii} growing on volcanic lava flow, Pinacate and Gran Desierto Altar Biosphere Reserve, Sonoran desert, Mexico

Jack Dykinga / Cerro Colorado volcano crater at sunset with Sierra de los Tanques in background, Biosphere Reserve of Pinacate and Gran Desierto Altar, Sonora, Mexico

Jack Dykinga / Sand dune patterns, Biosphere Reserve of Pinacate and Gran Desierto Altar, Sonoran desert, Mexico

Jack Dykinga / Mexico Teddy bear cholla cactus {Opuntia biegelovii} growing on volcanic lava flow, Pinacate and Gran Desierto Altar Biosphere Reserve, Sonoran desert, Mexico

Patricio Robles Gil / Gambel's Quail (Callipepla gambelii) adult perched atop a blooming cactus, El Pinacate/Gran Desierto de Altar Biosphere Reserve, Sonora, Mexico

Tom Vezo / Ferruginous Pygmy Owl (Glaucidium brasilianum) adult peering out from nest hole in Saguaro (Cereus gigantea) cactus, Altar Valley, Arizona

Claudio Contreras / Mojave desertstar (Monoptilon bellioides) flowers. Sierra El Rosario, El Pinacate Biosphere Reserve, Sonoran Desert.

Claudio Contreras / Evening primrose (Oenothera deltoides), Sand verbena (Abronia villosa) and Snowy sunflower (Helianthus niveus) in sand dune at dawn. Sierra El Rosario mountain range in background. El Pinacate Biosphe...

Claudio Contreras / Ocotillo (Fouquieria splendens) and Saguaro (Carnegiea gigantea) at sunset in Sonoran Desert. El Pinacate Biosphere Reserve, northwest Mexico.

Claudio Contreras / Brittlebush (Encelia farinosa) and Emory's rock daisy (Perytile emoryi). El Pinacate Biosphere Reserve, Sonoran Desert, northwest Mexico.

Claudio Contreras / Sonoran Desert with Teddy-bear cholla (Cylindropuntia bigelovii), Saguaro (Carnegiea gigantea) and Brittlebush (Encelia farinosa). El Colorado volcano in background. El Pinacate Biosphere Reserve, nor...