Christophe Courteau / Blue footed booby displaying {Sula nebouxii} Galapagos.

JIM CLARE / Galapagos hawk (Buteo galapagoensis) perched, Galapagos

Andy Rouse / Galapagos green turtle (Chelonia mydas agassisi) underwater portrait, being inquisitive, note algae growing on head and shell

Andy Rouse / Galapagos giant tortoise (Geochelone elephantopus / nigra) adult feeding, Santa Cruz, Galapagos

Kevin Schafer / Galapagos Marine Iguana (Amblyrhynchus cristatus) with Lava Lizard (Trpoidurus) on head. Fernandina island, Galapagos.

Andrew Cooper / Marine Iguana (Amblyrhynchus cristatus) on rocks with wave splash. Galapagos, Ecuador.

Kevin Schafer / Galapagos Sea Lion (Zalophus wollebaeki) pups playing, Espanola Island, Galapagos Islands, Ecuador

Tui De Roy / Marine iguana (Amblyrhynchus cristatus) males migrating to breeding areas at the onset of warm season. Galapagos Islands, Ecuador, December.

Tui De Roy / Marine iguanas (Amblyrhynchus cristatus) sky-pointing position to keep cool in sun. Punta Espinosa, Fernandina Island, Galapagos Islands, Ecuador, June.

Tui De Roy / Hood island giant tortoise (Chelonoidis nigra hoodensis) used for breeding program since 1960s, Tortoise Breeding Centre, Puerto Ayora, Santa Cruz Island, Galapagos Islands, Ecuador, Critically endang...

Tui De Roy / Great frigatebird (Fregata minor) male guarding single chick. Punta Cevallos, Espanola Island, Galapagos, Ecuador, May.

Tui De Roy / Volcan Alcedo giant tortoises (Chelonoidis nigra vandenburghi) wallowing in rain pools on caldera floor, possibly for thermoregulation or detering parasites, with sulphur fumaroles in background, Alce...

Tui De Roy / Wolf Volcano giant tortoise (Chelonoidis nigra becki) portrait, Isabela Island, Galapagos

Tui De Roy / Wolf-Volcano giant tortoise (Chelonoidis nigra becki) portrait with ground finch (Geospiza sp. ) sitting on foot, Isabela Island, Galapagos. Did you know? Galapagos tortoises have a mutualistic relati...

Tui De Roy / Short-eared owl (Asio flameus galapagoensis) looking between branches, portrait, Galapagos islands

Tui De Roy / Red-billed tropicbird (Phaethon aethereus) in flight over water. Galapagos Islands, Ecuador, May.

Tui De Roy / Red-billed tropicbird (Phaethon aethereus) in flight. Galapagos Islands, Ecuador.

Tui De Roy / Nazca boobies (Sula granti) against dawn sky. Espanola Island, Galapagos, Ecuador, May.

Tui De Roy / Yellow-crowned night heron (Nyctanassa / Nyctanassa violacea) portrait. Galapagos Islands, Ecuador, June.

Tui De Roy / Marine iguana (Amblyrhynchus cristatus) in profile against dark background. Galapagos Islands, Ecuador, December.

Tui De Roy / Marine iguana (Amblyrhynchus cristatus) in cloud of flies. Galapagos Islands, Ecuador, June.

Tui De Roy / Marine iguana (Amblyrhynchus cristatus) emerging from sea onto beach, with Sally lightfoot crabs (Grasopus graspus) and Galapagos Fur Seal in background. Galapagos Islands, Ecuador, June.

Tui De Roy / Great frigatebird (Fregata minor) male taking flight at dusk. Espanola Island, Galapagos, Ecuador, May.

Tui De Roy / Magnificent frigatebirds (Fregata magnificens) in low flight ovehead. Espanola Island, Galapagos, Ecuador, December.

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) portrait, covered in sand. Endangered. Seymour Island, Galapagos, Ecuador, June.

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) looking out to sea on sandy beach. Endangered. Espanola Island, Galapagos, Ecuador, June.

Tui De Roy / Galapagos penguins (Spheniscus mandiculus) standing on coastal volcanic rock. Endangered. Isabela Island, Galapagos, Ecuador, June.

Tui De Roy / Flightless Cormorant (Nannopterum / Phalacrocorax harrisi) with nesting material. Banks Bay, Isabela Island, Galapagos Islands, Ecuador, December.

Tui De Roy / Galapagos fur seal (Arctocephalus galapagoensis) large territorial bull on volcanic rocks. South Coast Cerro Azul (Cinco Cerros), Isabela, Galapagos Islands, Ecuador, June.

Tui De Roy / Flightless Cormorant (Nannopterum / Phalacrocorax harrisi) with chick at nest, made from dead starfish. Banks Bay, Isabela Island, Galapagos Islands, Ecuador, December.

Tui De Roy / Cactus finch (Geospiza scandens) feeding on cactus flower nectar and pollen. Espanola, Galapagos Islands, November.

Tui De Roy / Brown pelican (Pelecanus occidentalis) in flight above wave. San Cristobal Island, Galapagos, Ecuador, June.

Tui De Roy / American flamingo (Phoenicopterus ruber) feeding from water surface. Floreana Island, Galapagos, Ecuador, June.

Kevin Schafer / Galapagos land iguana (Conolophus subcristatus) Santa Cruz Is, Galapagos. Vulnerable species

Mark Carwardine / Marine Iguanas (Amblyrhynchus cristatus), the only marine lizard, basking on volcanic rocks. Galapagos Islands, Ecuador, South America. Book plate from Mark Carwardine's Ultimate Wildlife Experiences.

Todd Mintz / Galapagos sealion underwater (Zalophus californianus wollebaeki) Galapagos Islands, Pacific Ocean, November

Tui De Roy / Blue-footed Booby (Sula nebouxii) sky pointing during courtship dance, Galapagos Islands, Ecuador. Sequence 1 of 3

Tui De Roy / Greater Flamingo (Phoenicopterus ruber) pair in territorial display while two other feed, Galapagos Islands, Ecuador

John Abbott / Tourists watching large colony of Marine Iguanas (Amblyrhynchus cristatus) Punta Espinosa on Fernandina Island, Galapagos, August 2010

John Abbott / Giant prickly pear cactus (Opuntia echios var. gigantea) amongst carpetweed, Plazas Island, Galapagos

Ole Jorgen Liodden / Blue-footed Booby (Sula nebouxii) performing courtship display. Galapagos

Ole Jorgen Liodden / Magnificent Frigatebird (Fregata magnificens) male displaying, red throat pouch inflated. Galapagos

Ole Jorgen Liodden / Blue-footed Booby (Sula nebouxii) performing courtship display. Galapagos

Ole Jorgen Liodden / Galapagos Sea Lion (Zalophus wolllebaeki) under the surface. Galapagos

Ole Jorgen Liodden / Galapagos Ghost Crab (Ocypode gaudichaudii) fighting on the beach. Galapagos

Ole Jorgen Liodden / Galapagos Land Iguana (Conolophus subcristatus) silhouetted against dawn light. Galapagos

Ole Jorgen Liodden / Magnificent Frigatebird (Fregata magnificens)displaying in flight, red pouch inflated. Galapagos

Pete Oxford / Saddleback form of Galapagos Giant Tortoise (Chelonoidis nigra) walking, Wolf Volcano, Isabela Island, Galapagos

Pete Oxford / Galapagos penguin (Spheniscus mendiculus) diving underwater, Bartolome Island, Galapagos, endemic

Pete Oxford / Galapagos penguin (Spheniscus mendiculus) diving underwater, Bartolome Island, Galapagos, endemic.

Pete Oxford / Galapagos sealion (Zalophus wollebaeki) resting on rocks, Floreana Island, Galapagos

Bryan and Cherry Alexander / Tabular iceberg showing the portion underwater that is sculpted by the sea. Polar regions. Digitally created image composite

Andy Rouse / Marine Iguana (Amblyrhynchus cristatus) walking along beach. Cerro Dragon, Galapagos, September.

Andy Rouse / Marine Iguana (Amblyrhynchus cristatus) head profile. Punta Espinoza, Galapagos, October.

Andy Rouse / Two Marine Iguana (Amblyrhynchus cristatus) basking on a volcanic rock. Puerto Egas, Galapagos, September.

Andy Rouse / Marine Iguana (Amblyrhynchus cristatus) with friendly Lava Lizard (Tropidurus) perched on its head. Puerto Egas, Galapagos, September.

Andy Rouse / Marine Iguana (Amblyrhynchus cristatus) in water. Punta Espinoza, Galapagos, October.

Tim Laman / Marine Iguanas (Amblyrhynchus cristatus) on the south coast of Espanola Island, Galapagos, Vulnerable species

Tim Laman / Waved albatross (Phoebastria irrorata) head portrait, Galapagos, Critically endangered

Tim Laman / Waved Albatross (Phoebastria irrorata) in flight, soaring, Galapagos, Critically endangered

Tim Laman / Galapagos penguin (Spheniscus mendiculus) swimming off the coast of Bartolomew Island, Galapagos, Endangered species

Tim Laman / Galapagos penguin (Spheniscus mendiculus) swimming off the coast of Bartolomew Island, Galapagos, Endangered species

Pete Oxford / Galapagos Giant Tortoise (Geochelone elephantophus / Chelonoidis nigra) head portrait, Charles Darwin Research Station. Puerto Ayora,Santa Cruz Island, Galapagos, endemic

Pete Oxford / Small Ground Finch (Geospiza fuliginosa) being ringed for Avian pox research, Puerto Ayora, Santa Cruz Island, Galapagos, endemic

Pete Oxford / Great blue heron (Ardea herodias) portrait, Puerto Ayora, Santa Cruz Island, Galapagos Islands

Pete Oxford / Galapagos garden eels (Heteroconger / Taenioconger klausewitzi) on seabed, Galapagos Islands

Pete Oxford / Finch specimens at the Charles Darwin Research Station, Puerto Ayora, Santa Cruz Island, Galapagos Islands, L to R Top: Large Ground Finch (Geospiza magnirostris), Woodpecker Finch (Cactospiza pallidu...

Pete Oxford / Finch specimens (Emberizidae) at the Charles Darwin Research Station, Puerto Ayora, Santa Cruz Island, Galapagos Islands

Jeff Rotman / Bat rays (Myliobatis californica) schooling, Redondo Rock, Galapagos Is

Pete Oxford / Shoal of Yellowtail Grunts (Anisotremus interruptus) Floreana Island, Galapagos, Equador, Pacific ocean

Pete Oxford / Waved albatross (Phoebastria irrorata) in flight with storm clouds, Punto Cevallos, Española (Hood) Island, Galapagos islands, Equador, South America

Tui De Roy / Galapagos Sea Lion (Zalophus wollebaeki) female and pup nuzzling, Galapagos Islands, Ecuador

Tui De Roy / Great Frigatebird (Fregata minor) female guarding chick, Galapagos Islands, Ecuador

Juan Carlos Munoz / Galapagos giant tortoise {Geochelone elephantopus} cooling in water, Santa Cruz Island, Galapagos, January

Juan Carlos Munoz / Greater flamingo {Phoenicopterus ruber} feeding in coastal lagoon, Isabela Island, Galapagos, January

Juan Carlos Munoz / Blue footed booby {Sula nebouxii} diving, Galapagos, January

Juan Carlos Munoz / View from the caldera rim of the Chico Volcano, Sierra Negra, Isabela Island, Galapagos, January 2009

Juan Carlos Munoz / Galapagos giant tortoise {Geochelone elephantopus} head portrait, Santa Cruz Island, Galpagos, January

Juan Carlos Munoz / Close up of foot of a hiker on the caldera rim of Los Gemelos, Santa Cruz Island, Galapagos, January 2009. Model released.

Juan Carlos Munoz / Crab walking over beach leaving tracks in the wet sand, Floreana Island, Galapagos, January

Juan Carlos Munoz / Marine iguana {Amblyrhynchus cristatus} Plaza Island, Galapagos, January

Pete Oxford / Creolefish / Gringo (Paranthias colonus) Central Isles, Galapagos Islands

Pete Oxford / Rainbow runner (Elegatis bipinnulata) off Wolf Island, Galapagos Islands

Pete Oxford / Yellow-tailed mullet (Mugil rammelsbergii) feeding on plankton just below the surface, off Wolf Island Galapagos Islands

Pete Oxford / Finescale triggerfish (Balistes polylepis) off Wolf Island, Galapagos Islands

Pete Oxford / Diver follows shoal of Steel pompano (Trachinotus stilbe) off Wolf Island, Galapagos Islands, Model released

Pete Oxford / Measuring bill size of Waved albatross (Phoebastria irrorata) Punta Suarez, Española / Hood Island, Galapagos Islands

Pete Oxford / Waved albatross (Phoebastria irrorata) pair at nest after change over for incubation, Punta Suarez, Española Island, Galapagos Islands

Pete Oxford / Waved albatross (Phoebastria irrorata) portrait, Punta Cevallos, Espaola Island, Galapagos Islands

Pete Oxford / Waved albatross (Phoebastria irrorata) portrait, Punta Cevallos, Española Island, Galapagos Islands

Pete Oxford / Galapagos green turtle (Chelonia mydas agassizi) swimming underwater, off Wolf Island, Galapagos, Ecuador, South America

Pete Oxford / Yellow-tailed sawfish / surgeonfish (Prionurus laticlavius) shoal off Wolf Island, Galapagos Islands

Pete Oxford / Steel pompano fish (Trachinotus stilbe) cleaning Galapagos green turtle (Chelonia mydas agassizi) off Wolf Island, Galapagos Islands

Pete Oxford / Yellowtail sawtail / surgeonfish (Prionurus laticlavius) shoal off Wolf Island, Galapagos Islands

Pete Oxford / Waved albatross (Phoebastria irrorata) with water droplet falling from beak, Punta Cevallos, Española Island, Galapagos Islands

Pete Oxford / Waved albatross (Phoebastria irrorata) rear view, Punta Cevallos, Espaola Island, Galapagos Islands