860-291899 - False Clown Anemonefish (Amphiprion ocellaris) in Magnificent Sea Anemone (Heteractis magnifica), Tiga Batu dive site, Bangka Island, north Sulawesi, Indonesia, Pacific Ocean
1116-52869 - Portrait of a Cape Buffalo (Syncerus caffer) drinking from river carrying two cattle egrets (Bubulcus ibis) on its back in Chobe National Park, Chobe, Botswana
1116-52868 - Portrait of a Cape Buffalo (Syncerus caffer) drinking from river carrying two cattle egrets (Bubulcus ibis) on its back in Chobe National Park, Chobe, Botswana
832-401334 - Symbiotic behaviour Symbiosis of giant moray (Gymnothorax javanicus) with open mouth looks directly at observer lets cleaner wrasse bluestreak cleaner wrasse (Labroides dimidiatus) rid itself of parasites, Indian Ocean, Mascarene Islands, Mauritius, Africa
860-291421 - 27-year-old female researcher working on nitrogen exchange between bacteria and the roots of legumes showing an example of a nodule of bacteria attached to the roots in the rainforest of the "La Selva" research station in Puerto Viejo de Sarapiqui, Costa Rica
1116-39948 - This soft coral crab or candy crab (Hoplophrys oatesii), is wearing a decoration of soft coral polyps on top of head as camouflage, Dumaguete, Philippines
1116-39939 - An Imperial commensal shrimp (Periclimenes imperator), photographed at night on the Spanish dancer nudibranch (Hexabranchus sanguineus), that it calls home, Philippines
1116-39725 - Mouth detail of a colourful and healthy Mushroom coral, Fungia fungites, that is growing on a tropical coral reef in the Philippines. Mushroom coral is unique in the coral world, in that it does not attach itself to the bottom, Philippines
1116-39729 - Both a Crinoid Commensal Shrimp (Periclimenes cornutus) and a Crinoid Squat Lobster (Allogalathea elegans) on a crinoid. These tiny crustaceans are commensal on crinoids or feather stars and take their color from the host, Philippines
1116-39719 - A Slender Spongegoby (Phyllogobius platycephalops) and two different species of crabs. Attached to the goby are several parasites with egg cases, that will likely prove fatal over time. Many species live on the convuluted surface of this sponge, Philippin
1116-39735 - The strings hanging off the dorsal fin of this Great White Shark (Carcharodon carcharias) are parasitic copepods. Photographed just breaking the surface off Guadalupe Island, Mexico
1116-39953 - This hard coral colony in the Pacific has begun to bleach, expelling its symbiotic zooxanthellae, consequences of global climate change and climate warming, Yap, Micronesia
1116-39938 - Mouth detail of a colorful and healthy mushroom coral (Fungia fungites) that is growing on a tropical coral reef. Mushroom coral is unique in the coral world, in that it does not attach itself to the bottom, Philippines
465-3388 - Pink anenomefish (Amphoprion perideraion) dominant female, lives in symbiotic association with its host anemone, Matangi Island, Vanua Levu, Fiji, Pacific
465-3386 - Dusky anenomefish (Amphiprion melanomas) dominant female, lives in symbiotic association with its host anemone, Matangi Island, Vanua Levu, Fiji, Pacific
1067-65 - Coral polyps bleaching, Favia sp. Bleaching occurs when corals stress under high water temperatures and expel their symbiotic zooxanthellae. The coral will starve to death if it does not reacquire zooxanthellae. Buyat Bay, North Sulawesi, Indonesia, Pacific Ocean.
1067-59 - Soft leather coral, Sarcophyton sp., bleaching. This soft coral has lost its symbiotic algae, zooxanthellae, and turned white due to high water temperatures. Buyat Bay, North Sulawesi, Indonesia, Pacific Ocean.
1067-60 - Bleached soft coral, Sinularia sp. This colony has lost its symbiotic zooxanthellae and turned white due to high water temperatures. Buyat Bay, North Sulawesi, Indonesia, Pacific Ocean.
920-91 - Underwater photographer Masa Ushioda and Green sea turtle (Chelonia mydas) getting cleaned by yellow tangs (Zebrasoma flavescens) and lined bristletooth (Ctenochaetus striatus), Kailua-Kona, Hawaii, United States of America, Pacific
743-601 - Burchell's zebra foal (Equus burchelli), with redbilled oxpeckers (Buphagus erythrorhynchus), Hluhluwe Umfolozi Park, KwaZulu Natal, South Africa, Africa
743-600 - Burchell's zebra (Equus burchelli), with redbilled oxpeckers (Buphagus erythrorhynchus), Hluhluwe Umfolozi Park, KwaZulu Natal, South Africa, Africa
764-343 - Black rhinoceros or hook-lipped rhinoceros (Diceros bicornis) with yellow-billed oxpecker (Buphagus africanus), Masai Mara National Reserve, Kenya, East Africa, Africa
764-342 - Black rhinoceros or hook-lipped rhinoceros (Diceros bicornis) feeding, with yellow-billed oxpecker (Buphagus africanus), Masai Mara National Reserve, Kenya, East Africa, Africa