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

1315-65 - Oxpecker sitting on the forehead of an African Cape Buffalo in the Maasai Mara National Reserve, Kenya, East Africa, Africa

1174-5027 - A zebra, Equus quagga, stands with red-billed oxpeckers sitting on its back, Buphagus erythrorhynchus, Londolozi Game Reserve, Sabi Sands, Greater Kruger National Park, South Africa

1174-5148 - A hippopotamus's head half emerged under water, Hippopotamus amphibius, an African Jacana, Actophilornis africanus, sits on the hippos head, Londolozi Game Reserve, Sabi Sands, Greater Kruger National Park, South Africa

1174-5145 - A red-billed oxpecker, Buphagus erythrorhynchus, perches vertically on the tail of a buffalo, Syncerus caffer, direct gaze, Londolozi Game Reserve, Sabi Sands, Greater Kruger National Park, South Africa

1174-5141 - Two buffalo, Syncerus caffer, wallow and lie in the water, eyes closed, red-billed oxpeckers sit on them, Buphagus erythrorhynchus, Londolozi Game Reserve, Sabi Sands, Greater Kruger National Park, South Africa

1116-39727 - Clark's anemonefish (Amphiprion clarkii) in Beaded Sea Anemone (Heteractis aurora), 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

1116-39735 - 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

741-5387 - Yellow-billed oxpeckers (Buphagus africanus) on the back of an African buffalo (Syncerus caffer), Tsavo, Kenya, East Africa, Africa

764-5854 - Red-billed oxpecker (Buphagus erythrorhynchus) on a Cape buffalo (Syncerus caffer), Ngorongoro Crater, Tanzania, East Africa, Africa

764-5851 - Red-billed oxpecker (Buphagus erythrorhynchus) on a Cape buffalo (Syncerus caffer), Ngorongoro Crater, Tanzania, East Africa, Africa

1131-1004 - Indian rhinoceros (Rhinoceros unicornis) with Myna birds, Kaziranga National Park, Assam, India, Asia

764-5706 - Yellow-billed oxpecker (Buphagus africanus) on a Cape buffalo (Syncerus caffer), Kruger National Park, South Africa, Africa

743-1532 - Giraffe (Giraffa camelopardalis) with redbilled oxpecker, Kruger National Park, South Africa, Africa

1249-23 - Red-billed oxpecker (Buphagus erythrorhynchus), Ngorongoro Conservation Area, Tanzania, East Africa, Africa

743-1430 - Giraffe (Giraffa camelopardalis) with redbilled oxpeckers (Buphagus erythrorhynchus), Kruger National Park, South Africa, Africa

743-1337 - Cape mountain zebra (Equus zebra zebra), with pied crow (Corvus albus), Mountain Zebra National Park, Eastern Cape, South Africa, Africa

764-5314 - Impala (Aepyceros melampus) with a red-billed oxpecker (Buphagus erythrorhynchus), Kruger National Park, South Africa, Africa

10-336 - Cow and crane, who share a simbiotic relationship, Talpe, Sri Lanka, Asia

764-4399 - Red-billed oxpecker (Buphagus erythrorhynchus) on a female impala (Aepyceros melampus), Kruger National Park, South Africa, Africa

1012-140 - Loggerhead Turtle (Caretta caretta) sub-adult. Azores, Portugal Atlantic

1012-139 - Loggerhead Turtle (Caretta caretta) and Pilot Fish (Naucrates ductor). Azores, Portugal, Atlantic

1012-175 - Scalloped Hammerhead Shark being cleaned by Barbar Fish. CoCos Island, Costa Rica.

1012-192 - Spine-Cheek Anemonefish (Premnas biaculeatus) on Bubble Anemone, Entacmaea quadricolor. Gorontalo, Sulawesi, Indonesia. (rr)

1012-138 - Loggerhead Turtle (Caretta caretta) and Pilot Fish (Naucrates ductor). Azores, Portugal, Atlantic.

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.

931-526 - Sperm whale (physeter macrocephalus) . Two remora on a sperm whale. Eastern Caribbean

931-527 - Sperm whale (physeter macrocephalus) . A close up view of remora on a sperm whale. Eastern Caribbean

1015-42 - Clown anemonefish (Amphiprion percula). Indo Pacific

1015-105 - Giant manta ray overhead (Manta biostris). Mexico.

1015-52 - Nudibranch pair & cleaner shrimp (Risbecia tryoni). Indo Pacific

970-489 - Spotted Cleaner shrimp (Periclemenes yucatanicus) on anemone, Curacao, Netherlands Antilles. Caribbean.

1015-330 - Whale Shark with diver. (rr)

970-18 - Whaleshark (Rhyncodon typus),looking to head with pilotfish and Scuba Diver, Seychelles, Indian Ocean

1015-249 - Lizardfish (Synodus variagatus). Indo Pacific

1015-43 - Moray eel with cleaner shrimp (Gymnothorax sp).

1015-199 - Cleaner shrimp on red gorgonian.Indo Pacific

1015-89 - Giant manta ray, overhead (Manta birostris). Mexico, Revillagigedo Is.

1015-104 - Giant manta ray & photographer on scuba (Manta biostris). Mexico

1015-155 - Spine-cheek anemonefish (Premnas biaculeatu). Papua New Guinea

1015-197 - Cleaner shrimp on jellyfish. Indo Pacific

1015-262 - Cleaner shrimp works on moray eel.

970-165 - Spine-cheek anemone fish (Premnas biaculeatus), nice red anemonefish with white stripes and prominant spine on cheek, Sipadan Island, Malaysia

1015-57 - Clown anemonefish (Amphiprion percula).

1015-54 - Giant manta ray (Manta birostris). Mexico, Revillagigedo Is.

1015-56 - Giant manta ray with Clarion angelfish (Manta birostris & Holocanthus clarionensis). Mexico, Revillagigedo Is.

1015-55 - Giant manta ray, ventral view (Manta birostris). Mexico, Revillagigedo Is.

1015-100 - Starry Toadfish; cleaner shrimp on mouth (Arothon stellatus). Indo Pacific

920-111 - A diver observes 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

920-102 - Green sea turtle (Chelonia mydas) getting cleaned by yellow tangs (Zebrasoma flavescens) and lined bristletooth (Ctenochaetus striatus), Kailua-Kona, Hawaii, Pacific

920-112 - Green sea turtle (Chelonia mydas) getting cleaned by yellow tangs (Zebrasoma flavescens) and lined bristletooth (Ctenochaetus striatus), Kailua-Kona, Hawaii, Pacific

920-106 - Green sea turtle (Chelonia mydas) getting cleaned by yellow tangs (Zebrasoma flavescens) and lined bristletooth (Ctenochaetus striatus), Kailua-Kona, Hawaii, Pacific

920-101 - Green sea turtle (Chelonia mydas) getting cleaned by yellow tangs (Zebrasoma flavescens) and lined bristletooth (Ctenochaetus striatus), Kailua-Kona, Hawaii, Pacific

817-213734 - Leaf-cutter ants Atta cephalotes cutting leaf fragments in Costa Rica

788-10454 - Two Spine Cheek anemone fish (Premnas biaculeatus) swimming underwater, Papua New Guinea

788-10290 - Oxpecker on the neck of a male Kudu (Tragelaphus strepsiceros), Kruger National Park, Mpumalanga Province, South Africa