Claudio Contreras / Western Sandpiper (Calidris mauri), El Vizcaino Biosphere Reserve, Baja California Peninsula, Mexico, December.

Claudio Contreras / Brent geese (Branta bernicla), El Vizcaino Biosphere Reserve, Baja California Peninsula, Mexico, December.

Claudio Contreras / Short-Billed Dowitcher (Limnodromus griseus), El Vizcaino Biosphere Reserve, Baja California Peninsula, Mexico, December.

Tim Fitzharris / Cadlao Island near El Nido, Palawan, Philippines

Tui De Roy / Leopard (Panthera pardus), El Karama Ranch, Kenya

Tui De Roy / Gerenuk (Litocranius walleri) females browsing, El Karama Ranch, Kenya

Tui De Roy / Grant's Gazelle (Nanger granti) herd, El Karama Ranch, Kenya

Tui De Roy / Gerenuk (Litocranius walleri) male browsing, El Karama Ranch, Kenya

Tui De Roy / Gerenuk (Litocranius walleri) male browsing, El Karama Ranch, Kenya

Tui De Roy / Gerenuk (Litocranius walleri) male browsing, El Karama Ranch, Kenya

Tui De Roy / Dwarf Mongoose (Helogale parvula) group on termite mound, El Karama Ranch, Kenya

Tui De Roy / Cheetah (Acinonyx jubatus) males scent marking tree, El Karama Ranch, Kenya

Tui De Roy / Cheetah (Acinonyx jubatus), El Karama Ranch, Kenya

Daniel Heuclin / Giant Coot (Fulica gigantea) male collecting mesting material. Near El paso las viscachas (4450 m), northern Chile.

Konrad Wothe / Um el Ma oasis and sand dunes, Libyan desert, Libya, Sahara, Africa, December 2007

Konrad Wothe / Um el Ma oasis with date palms and sand dunes, Libyan desert, Libya, Sahara, North Africa, December 2007

Alex Mustard / Bluespotted stingray (Taeniura lymma) disguised as it lays buried in sand. Na'ama Bay, Sharm El Sheikh, Egypt. Gulf of Aqaba, Red Sea.

Roland Seitre / Mygalomorph Spider (Mygalomorpha sp.) San Jose del Palmar, El Cairo, Choco, Valle del Cauca, Colombia.

Roland Seitre / White-vented Plumeleteer (Chalybura buffonii) feeding from red flower. El Valle, Panama.

Merryn Thomas / Paleoliquefaction features - evidence of paleo-earthquakes - at El Medano beach, Southern Tenerife, Canary Islands, April 2011.

Merryn Thomas / Students studying Paleoliquefaction features, evidence of paleo-earthquakes, at El Medano beach, South Tenerife, Canary Islands, April 2011.

Claudio Contreras / Detail of Ocellated Turkey (Meleagris / Agriocharis ocellata) plumage. El Mirador-Rio Azul National Park, Department of Peten, Guatemala.

Claudio Contreras / Detail of Ocellated Turkey (Meleagris / Agriocharis ocellata) plumage. El Mirador-Rio Azul National Park, Department of Peten, Guatemala.

Claudio Contreras / Ocellated Turkey (Meleagris / Agriocharis ocellata). El Mirador-Rio Azul National Park, Department of Peten, Guatemala.

Claudio Contreras / Ocellated Turkey (Meleagris / Agriocharis ocellata). El Mirador-Rio Azul National Park, Department of Peten, Guatemala.

Claudio Contreras / Ocellated Turkey (Meleagris / Agriocharis ocellata). El Mirador-Rio Azul National Park, Department of Peten, Guatemala.

Claudio Contreras / Ocellated Turkey (Meleagris / Agriocharis ocellata) portrait. El Mirador-Rio Azul National Park, Department of Peten, Guatemala.

Claudio Contreras / Ocellated Turkey (Meleagris / Agriocharis ocellata) portrait. El Mirador-Rio Azul National Park, Department of Peten, Guatemala.

Claudio Contreras / Ocellated Turkey (Meleagris / Agriocharis ocellata). El Mirador-Rio Azul National Park, Department of Peten, Guatemala.

Claudio Contreras / Tamaulipan False Brook Salamander (Pseudoeurycea scandens) on cave wall. El Cielo Biosphere Reserve, northeast Mexico, November.

Claudio Contreras / Flat-tailed Horn Lizard (Phrynosoma mcallii). Sonoran desert, El Pinacate Biosphere Reserve, northwest Mexico, July.

Claudio Contreras / Flat-tailed Horn Lizard (Phrynosoma mcallii). Sonoran desert, El Pinacate Biosphere Reserve, northwest Mexico, July.

Kristel Richard / A traditionally dressed cowboy is thrown out by a bronc (unbroken) Quarter mare, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay. January 2012

Kristel Richard / A traditionally dressed cowboy tries to remain on a bronc (unbroken) Quarter mare, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay. Sequence 2/2. Januar...

Kristel Richard / A traditionally dressed cowboy tries to remain on a bronc (unbroken) Quarter mare, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay. Sequence 1/2. Januar...

Kristel Richard / A bronc (unbroken) Quarter mare bolts after having thrown out a traditionally dressed cowboy, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay. Sequence...

Kristel Richard / A traditionally dressed cowboy has fallen under a bolting bronc (unbroken) Quarter mare, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay. Sequence 6/7....

Kristel Richard / A traditionally dressed cowboy tries to remain on a fallen bronc (unbroken) Quarter mare, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay. Sequence 5/7....

Kristel Richard / A traditionally dressed cowboy tries to remain on a bronc (unbroken) Quarter mare, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay. Sequence 4/7. Januar...

Kristel Richard / Traditionally dressed cowboys try to saddle a bronc (unbroken) Quarter mare tied to a pillar, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay. Sequence...

Kristel Richard / Traditionally dressed cowboys saddle a bronc (unbroken) Quarter mare tied to a pillar, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay. Sequence 2/7. Ja...

Kristel Richard / Traditionally dressed cowboys saddle a bronc (unbroken) Quarter mare tied to a pillar, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay. Sequence 1/7. Ja...

Kristel Richard / A traditionally dressed cowboy tries to remain on a bronc (unbroken) Quarter gelding, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay, January 2012

Kristel Richard / A traditionally dressed cowboy tries to remain on a bronc (unbroken) Quarter gelding, during the rodeo of the Festival de la Doma y el Folclore, Estancia Tacuaty, Misiones, Paraguay, January 2012

Daniel Heuclin / Andean goose (Chloephaga melanoptera) landing on water, near El Paso Las Viscachas, 4450 m. Bolivian Altiplano.

Daniel Heuclin / Andean goose (Chloephaga melanoptera) two standing with mountains in background, near El Paso Las Viscachas, 4450 m. Bolivian Altiplano.

Daniel Heuclin / Andean goose (Chloephaga melanoptera) wading in shallow water, feeding, near El Paso Las Viscachas, 4450 m. Bolivian Altiplano.

Roland Seitre / Toad Mimic rainfrog (Strabomantis / Craugastor bufoniformis) El Valle Amphibian Conservation Center, Panama, Central America

Roland Seitre / Banded Horned Treefrog (Hemiphractus fasciatus / Cerathyla panamensis) El Valle Amphibian Conservation Center, Panama, Central America, near threatened species

Roland Seitre / Banded Horned Treefrog (Hemiphractus fasciatus / Cerathyla panamensis) El Valle Amphibian Conservation Center, Panama, Central America, near threatened species

Roland Seitre / Lemur leaf frog (Hylomantis / Phyllomedusa lemur) El Valle Amphibian Conservation Center, Panama, Central America, Critically Endangered species

Roland Seitre / Giant Glass Frog (Sachatamia / Centrolene ilex) El Valle Amphibian Conservation Center, Panama, Central America

Roland Seitre / Rusty robber frog (Strabomantis bufoniformis) El Valle Amphibian Conservation Center, Panama, Central America

Roland Seitre / Vicente's poison frog (Oophaga / Dendrobates vicentei) El Valle Amphibian Conservation Center, Panama, Central America

Roland Seitre / Rear detail of Marsupial treefrog (Gastrotheca cornuta) showing pouch of female, El Valle Amphibian Conservation Center, Panama, Central America

Roland Seitre / Marsupial treefrog (Gastrotheca cornuta) female, El Valle Amphibian Conservation Center, Panama, Central America

Roland Seitre / Frog breeding tanks at the El Valle Amphibian Conservation Center, Panama, Central America, March 2008

Roland Seitre / Banded horned treefrog (Hemiphractus fasciatus / Cerathyla panamensis) El Valle Amphibian Conservation Center, Panama, Central America, near threatened species

Roland Seitre / Frog breeding tanks at the El Valle Amphibian Conservation Center, Panama, Central America, March 2008

Roland Seitre / Conservation officer, Edgardo Griffith, examines a Crowned tree frog (Anotheca spinosa) for fungal parasitic skin disease at El Valle Amphibian Conservation Center, Panama, Central America, March 2008

Roland Seitre / Conservation officer, Edgardo Griffith, examines a Crowned tree frog (Anotheca spinosa) for fungal parasitic skin disease at El Valle Amphibian Conservation Center, Panama, Central America, March 2008

Roland Seitre / Conservation officers, Edgardo and Heidi Griffith, examine a Crowned tree frog (Anotheca spinosa) for fungal parasitic skin disease at El Valle Amphibian Conservation Center, Panama, Central America,...

Roland Seitre / Crowned tree frog (Anotheca spinosa) at El Valle Amphibian Conservation Center, Panama, Central America, March 2008

Roland Seitre / Conservation officer, Heidi Griffith, with Crowned tree frog (Anotheca spinosa) at El Valle Amphibian Conservation Center, Panama, Central America, March 2008

Roland Seitre / Frog tank at the El Valle Amphibian Conservation Center, Panama, Central America, March 2008,

Roland Seitre / Frog (Strabomantis bufoniformis) held in hand at the El Valle Amphibian Conservation Center, Panama, Central America, March 2008

Roland Seitre / Conservation officer carries out leg surgery on a Panamanian golden frog / Golden arrow poison frog (Atelopus zeteki) at the El Valle Amphibian Conservation Center, Panama, Central America, March 2008...

Roland Seitre / Conservation officer administers anti-parasite treatment to Panamanian golden frog / Golden arrow poison frog (Atelopus zeteki) at the El Valle Amphibian Conservation Center, Panama, Central America,...

Roland Seitre / Conservation officer administers anti-parasite treatment to Panamanian golden frog / Golden arrow poison frog (Atelopus zeteki) at the El Valle Amphibian Conservation Center, Panama, Central America,...

Roland Seitre / Conservation officer administers anti-parasite treatment to Panamanian golden frog / Golden arrow poison frog (Atelopus zeteki) at the El Valle Amphibian Conservation Center, Panama, Central America,...

Roland Seitre / Panamanian golden frog / Golden arrow poison frog (Atelopus zeteki) female with eggs, El Valle Amphibian Conservation Center, Panama, Central America, March 2008, Critically endangered species

Roland Seitre / Veterinary officer, Eric Baitchman, and Conservation officer, Heidi Griffith, examining female Panamanian golden frog / Golden arrow poison frog (Atelopus zeteki) at frog breeding station, El Valle Am...

Roland Seitre / Conservation officer demonstrates Panamanian golden frog / Golden arrow poison frog (Atelopus zeteki) female with eggs, El Valle Amphibian Conservation Center, Panama, Central America, March 2008, Cri...

Roland Seitre / Conservation officer, Heidi Griffith, holds Panamanian golden frog / Golden arrow poison frog (Atelopus zeteki) at frog breeding station, El Valle Amphibian Conservation Center, Panama, Central Americ...

Roland Seitre / Conservation officer, Heidi Griffith, holds a Crowned tree frog (Anotheca spinosa) at frog breeding station, El Valle Amphibian Conservation Center, Panama, Central America, March 2008

Oriol Alamany / El Salto Grande waterfall, Torres del Paine National Park, Patagonia, Chile

Doug Wechsler / Herrania (Sterculiaceae) in flower. Buenaventura Reserve, El Oro Province, Ecuador.

Jeff Rotman / El Molo child suffering from rickets, caused by a diet consisting primarily of fish. El Molo children suffer from vitamin D deficiency, which develops into the nutritional disease causing deformities...

Jeff Rotman / El Molo warriors and tribal people dancing during the Hippopotamus Ceremony, Lake Turkana, Kenya April 2008.

Jeff Rotman / El Molo warriors and tribal people dance during the Hippopotamus Ceremony, Lake Turkana, Kenya, April 2008.

Jeff Rotman / El Molo warriors pulling out the pole spears from a dead Hippopotamus (Hippopotamus amphibius) killed in their hunt, Lake Turkana, Kenya, April 2008.

Juergen Freund / Hook and line fishermen allowed to fish in protected municipal waters. El Nido, Palawan, Phillipines, May 2009.

Juergen Freund / Miniloc Island Resort at dusk. El Nido, Palawan, Phillipines, May 2009.

Inaki Relanzon / Ermita de Nuestra Senora de Candelaria (Nuestra Senora de Candelaria Church) in a vast mountain landscape. Frontera, east coast of El Hierro Island, Canary Islands, , February 2011.

Inaki Relanzon / Ermita de Nuestra Senora de Candelaria (Nuestra Senora de Candelaria Church) in a vast mountain landscape. Frontera, east coast of El Hierro Island, Canary Islands, , February 2011.

Inaki Relanzon / Vegetation growing from volcanic rocks sloping down to the sea. The east coast of El Hierro Island, Canary Islands, February 2011.

Inaki Relanzon / Thousand-year-old Sabina / Canary Juniper, (Juniperus turbinata canariensis) against a night sky with star trails. El Sabinar, El Hierro Island, Canary Islands, , February 2011.

Inaki Relanzon / "The Roque de Bonanza" in dusky evening light. The east coast of El Hierro Island, Canary Islands, February 2011.

Juergen Freund / Artificial reef using ceramic snowflakes help rejuvenate the dead coral reefs of El Nido. The 1998 El Nino caused a massive scale coral bleaching to this tourist town that used to have pristine coral...

Juergen Freund / Artificial reef using ceramic snowflakes help rejuvenate the dead coral reefs of El Nido. The 1998 El Nino caused a massive scale coral bleaching to this tourist town that used to have pristine coral...

Juergen Freund / Sergeant major damselfish (Abudefduf vaigiensis), Parrotfish and Wrasses in the house reef of Miniloc Island Resort, El Nido, Palawan, Philippines. These fish come together densely when bread is throw...

Juergen Freund / Giant trevally (Caranx ignobilis) chasing schooling Oxeye Scads (Selar boops) house reef of Miniloc Island Resort, El Nido Island, Palawan, Philippines.

Juergen Freund / Sargassum seaweed (Sargassum sp) floating at the surface, split level, El Nido, Palawan, Philippines, May.

Juergen Freund / Artificial reef made of ceramic snowflakes to help rejuvenate the dead reef of El Nido. The 1998 El Nino caused a massive scale coral bleaching to this tourist town that used to have pristine coral re...

Juergen Freund / Artificial reef using ceramic snowflakes help rejuvenate the dead coral reefs of El Nido. The 1998 El Nino caused a massive scale coral bleaching to this tourist town that used to have pristine coral...