Joel Sartore / Photo Ark / Baltimore oriole (Icterus galbula) male, portrait, from the wild, Hudson, Wisconsin, USA.

Joel Sartore / Photo Ark / Large fig parrot (Psittaculirostris desmarestii desmarestii) portrait, Prague Zoo. Captive, occurs in Indonesia and Papua New Guinea.

Joel Sartore / Photo Ark / Canada warbler (Cardellina canadensis) portrait, from the wild. Hudson, Wisconsin, USA. May.

Joel Sartore / Photo Ark / Wilson's warbler (Cardellina pusilla pusilla) portrait, Wildlife Rehab Center of Minnesota, USA. Captive.

Joel Sartore / Photo Ark / New Zealand kaka (Nestor meridionalis septentrionalis) portrait, Wellington Zoo, New Zealand. Captive.

Joel Sartore / Photo Ark / Red-winged blackbird (Agelaius phoeniceus) male, portrait, Tracy Aviary and Botanical Gardens, Utah, USA. Captive.

Joel Sartore / Photo Ark / Common grackle (Quiscalus quiscula versicolor) with mouth open, portrait, from the wild, Fort Hood, Texas, USA.

Joel Sartore / Photo Ark / Mountain cottontail rabbit (Sylvilagus nuttallii pinetis) juvenile, portrait, New Mexico Wildlife Center, New Mexico, USA. Captive.

Joel Sartore / Photo Ark / Eastern chipmunk (Tamias striatus) portrait, Zoo New York, USA. Captive.

Joel Sartore / Photo Ark / Eastern chipmunk (Tamias striatus) portrait, Zoo New York, USA. Captive.

David Hall / RF - Threadfin hawkfish (Cirrhitichthys aprinus) resting on soft coral (Nephtheidae),Triton Bay, West Papua, Pacific Ocean. (This image may be licensed either as rights managed or royalty free.)

David Hall / RF - Bluestreak fusiliers (Pterocaesio tile) school feeding on plankton above purple and magenta Soft corals (Dendronephthya sp.) with Solitary tunicates (Polycarpa aurata), Compound ascidians (Ascidi...

David Hall / RF - Banded sea krait (Laticauda sp.) swimming close to surface, Raja Ampat, Indonesia, Pacific Ocean. (This image may be licensed either as rights managed or royalty free.)

David Hall / RF - Gorgonian coral sea fans (Melithaea sp.) with Yellowtail fusiliers (Caesio cuning) and Banana fusiliers (Pterocaesio pisang) feeding on zooplankton in midwater. Also seen among the sea fans are D...

David Hall / RF - Coral reef scene with Sea fans (Melithaea sp.) and (Echinogorgia sp.), soft corals (Dendronephthya sp.) and (Umbellulifera sp.) and Threadfin anthias (Pseudanthias huchti), Raja Ampat, Indonesia...

David Hall / RF - Group of Red lionfish (Pterois volitans) engaging in cooperative hunting over coral reef, displaying aggression with venomous spines erect, possible defensive behaviour, Raja Ampat, Indonesia, Pa...

David Hall / RF - False clown anemonefish (Amphiprion ocellaris) pair and juvenile, living among their Magnificent sea anemone (Heteractis magnifica) home, Raja Ampat, Indonesia, Pacific Ocean. (This image may be...

David Hall / RF - Yellowtail fusiliers (Caesio cuning) school swimming over a reef with many healthy soft and hard corals, with an Eyestripe surgeonfish (Acanthurus dussumieri) among them, Raja Ampat, Indonesia, P...

David Hall / RF - Red lionfish (Pterois volitans) swimming over reef with soft corals (Dichotella sp. and Sinularia sp.) and reef fish, Raja Ampat, Indonesia, Pacific Ocean. (This image may be licensed either as r...

David Hall / RF - Large orange Sea fan (Melithaea sp.) with Feather stars (Crinoidea) and Soft corals (Nephtheidae) on reef wall, Raja Ampat, Indonesia, Pacific Ocean. (This image may be licensed either as right...

David Hall / RF - Coral reef scene with Gorgonian sea fan (Melithaea sp.), Feather stars (Crinoidea), Saddle grouper (Cephalopholis sexmaculata) and Blacklip butterflyfish (Chaetodon kleinii). Also present are se...

David Hall / RF - Coral reef scene with Gorgonian coral sea fans (Melithaea sp.), Soft corals (Nephtheidae) and Featherstars (Crinoidea), Raja Ampat, Indonesia, Pacific Ocean. (This image may be licensed either as...

David Hall / RF - Reef overhang with Sea fans (Melithaea), orange Cup corals (Dendrophylliidae), Soft corals (Dendronephthya sp.), red Encrusting sponges (Porifera), Solitary tunicates (Polycarpa sp.) and Anthias...

David Hall / RF - Group of Feather stars (Crinoidea) resting on an unidentified coral sea fan, Raja Ampat, Indonesia, Pacific Ocean. (This image may be licensed either as rights managed or royalty free.)

David Hall / RF - Banded archerfish (Toxotes jaculatrix) school swimming among mangroves, Raja Ampat, Indonesia, Pacific Ocean. (This image may be licensed either as rights managed or royalty free.)

David Hall / Vermiculate rabbitfish (Siganus vermiculatus) school swimming among mangrove roots, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Underwater cave with Dusky sweepers (Pempheris adusta) and Soldierfish (Myripristis sp.). The walls of the cave are covered with sessile invertebrates, including Soft corals (Nephtheidae), Cup corals...

David Hall / Underwater cave with Soft corals (Nephtheidae), Cup corals (Dendrophylliidae), Black corals (Antipatharia), Dusky sweepers (Pempheris adusta), Soldierfish (Myripristis sp.) and Eyestripe surgeonfish (...

David Hall / Tassled wobbegong (Eucrossorhinus dasypogon) resting on seabed under a ledge inside a small cave, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Tassled wobbegong (Eucrossorhinus dasypogon) resting on seabed under a ledge inside a small cave with Red soldierfish (Myripristis sp.) behind, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Ribbon sweetlips (Plectorhinchus polytaenia) top, Oriental sweetlips (Plectorhinchus vittatus) and Diagonal-banded sweetlips (Plectorhinchus lineatus) sheltering together in a small cave, Raja Ampat,...

David Hall / Two Signal gobies (Signigobius biocellatus) side by side, portrait, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / School of Slender fusiliers (Gymnocaesio gymnoptera) swimming over reef in shallow water, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / School of Sleek unicornfish (Naso hexacanthus) swimming over a coral reef, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / School of Slender fusiliers (Gymnocaesio gymnoptera) swimming over coral reef with Sea fan (Melithaea sp.) and Soft corals (Sarcophyton sp.), Raja Ampat, Indonesia, Pacific Ocean.

David Hall / A coral reef scene with red Sea fans (Melithaea sp.) and Threadfin anthias (Pseudanthias huchti). Also present are hard plate corals, Wire coral (Cirrhipathes sp.), red Encrusting sponge (Porifera), B...

David Hall / Map puffer (Arothron mappa) swimming over coral reef with Soft corals (Dendronephthya sp.), Threadfin anthias (Pseudanthias huchti) and Damselfish (Pomacentridae), Raja Ampat, Indonesia, Pacific Ocean...

David Hall / False clown anemonefish (Amphiprion ocellaris) pair swimming around a Magnificent sea anemone (Heteractis magnifica) with Soft coral (Sinularia sp.), Branching hard coral (Acropora sp.) and blue Encru...

David Hall / Red lionfish (Pterois volitans) swimming over coral reef with Soft corals, from left to right (Dichotella sp.), (Sinularia sp.), (Nephthea sp.) and Hard coral (Acropora sp.), Raja Ampat, Indonesia, Pa...

David Hall / A large, mixed aggregation of fish swimming through a reef cut, including (from top to bottom) Eyestripe surgeonfish (Acanthurus dussumieri), Yellowtail fusiliers (Caesio cuning), Sergeant damselfish...

David Hall / Picturesque dragonet (Synchiropus picturatus) resting on seabed, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Polyclad flatworms (Pseudobiceros sp.) pair, on seabed preparing to mate, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Polyclad flatworms (Pseudobiceros sp.) pair, mating on seabed, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Mangrove roots with Soft corals (Dendronephthya sp.) and decaying mangrove leaves, Misool, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Mangrove roots with colorful Soft corals (Dendronephthya sp.) on seabed and Banded archerfish (Toxotes jaculatrix) swimming above near the surface, Misool, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Mangrove red snapper (Lutjanus argentimaculatus) swimming among mangrove roots with Soft corals (Dendronephthya sp.) and green algae (Halimeda sp.), Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Schooling Banded archerfish (Toxotes jaculatrix) swimming among mangrove roots, Misool, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Mangrove ecosystem with algae (Halimeda), Sponges (Porifera), Solitary tunicates (Polycarpa sp.), Colonial ascidians (Atriolum sp.), a mound-like Hard coral colony (Faviidae), and feather-like Colonia...

David Hall / Humpback grouper (Cromileptes altivelis) juvenile, portrait, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Indian mackerel (Rastrelliger kanagurta) school, swimming with open mouths while feeding on zooplankton, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Headshield slug (Chelidonura amoena) portrait, Triton Bay, West Papua, Indonesia, Pacific Ocean.

David Hall / Threadfin hawkfish (Cirrhitichthys aprinus) camouflaged amongst orange Soft coral (Dendronephthya sp.), Triton Bay, West Papua, Indonesia, Pacific Ocean.

David Hall / Black corals (Antipatharia), Orange sea fan (Alcyonacea) and several dark Feather stars (Comatulida) on coral reef, Triton Bay, West Papua, Indonesia, Pacific Ocean.

David Hall / Clown triggerfish (Balistoides conspicillum) female, guarding a large cluster of yellow eggs, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Majid decorator crab (Cyclocoeloma tuberculata) covering itself with stinging Cnidarians (Corallimorpharia) for camouflage and defence, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Sleek unicornfish (Naso hexacanthus) aggregation feeding on zooplankton above coral reef with Branching hard corals (Acropora sp.), Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Gorgonian coral sea fans (Melithaeidae) with Black featherstars (Comatulida) and Banana fusiliers (Pterocaesio pisang) on coral reef, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Gorgonian coral sea fans (Subergorgiidae) and Black featherstars (Crinoidea) on coral reef, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Five Red lionfish (Pterois volitans) hunting cooperatively over coral reef with Red sea whip colony (Ellisella sp.) in foreground and reef fish, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Moorish idol (Zanclus cornutus) swimming past a reef covered with Coral sea fans including (Melithaea sp.) and (Pseudopterogorgia sp.), Soft corals (Dendronephthya sp), (Chironephthya sp.) and (Sclero...

David Hall / Red sea whips (Ellisella sp.), Yellow sea fan (Annella sp.), Soft corals (Dendronephthya sp.) and (Sarcophyton sp.) and Featherstars (Crinoidea) on coral reef, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Gorgonian sea fans (Melithaea sp.), Hard corals (Scleractinia), Grey tube sponges (Porifera), Feather stars (Crinoidea), Damselfish (Pomacentridae), Anthias (Anthias sp.), and other coral reef fish, R...

David Hall / Coral reef scene with Yellow boxfish (Ostracion cubicus), orange Cup corals (Dendrophyllia sp.), Branching hard corals (Acropora sp.), Sea fans (Melithaea sp.), red Soft coral (Dendronephthya sp.), Or...

David Hall / Two Coral groupers (Cephalopholis miniata) swimming over coral reef with several kinds of Soft corals including (Nephtheida) and (Plexauridae). Additional invertebrates include Hydrozoans (Stylaster s...

David Hall / Black coral (Antipatharia) forest with Surgeonfish (Acanthuridae), Cardinalfish (Apogonidae) and schooling Sweepers (Pempheridae), Triton Bay, West Papua, Indonesia, Pacific Ocean.

David Hall / Group of Bigfin reef squid (Sepioteuthis lessoniana) swimming over a coral reef, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Banded archerfish (Toxotes jaculatrix) school swimming among mangrove roots, Misool, Raja Ampat, Indonesia, Pacific Ocean.

David Hall / Banded archerfish (Toxotes jaculatrix) school swimming among mangrove roots, Misool, Raja Ampat, Indonesia, Pacific Ocean.

Nick Garbutt / RF - Mantled howler monkey (Alouatta palliata) resting on branch in rainforest canopy, Osa Peninsula, Costa Rica. (This image may be licensed either as rights managed or royalty free.)

Nick Garbutt / Central American spider monkey (Ateles geoffroyi) female with infant feeding on palm fruits, Osa Peninsula, Costa Rica. Endangered.

Nick Garbutt / Mantled howler monkey (Alouatta palliata) resting on branch, calling, in rainforest canopy, Osa Peninsula, Costa Rica.

Nick Garbutt / Mantled howler monkey (Alouatta palliata) resting on branch in rainforest canopy, Osa Peninsula, Costa Rica.

Nick Garbutt / Two Mantled howler monkeys (Alouatta palliata) sitting on branch in rainforest canopy, one calling, Osa Peninsula, Costa Rica.

Nick Garbutt / Two Mantled howler monkeys (Alouatta palliata) sitting on branch in rainforest canopy, Osa Peninsula, Costa Rica.

Nick Garbutt / Group of Andean condors (Vultur gryphus) basking on snow-covered ground after feeding on a nearby Guanaco carcass, near Torres del Paine National Park, Patagonia, Chile.

Nick Garbutt / Group of Black-and-gold howler monkeys (Alouatta caraya) juvenile males and females with an infant, sitting on tree branch, Cuiaba River, Pantanal, Brazil.

Nick Garbutt / Group of Black-and-gold howler monkeys (Alouatta caraya) juvenile males and females with an infant, sitting on tree branch, Cuiaba River, Pantanal, Brazil.

Joel Sartore / Photo Ark / Kanawha darter (Etheostoma kanawhae) male, portrait, from the New River drainage, Virginia. Photographed at the Aquatic Wildlife Conservation Center, Virginia, USA. Captive.

Joel Sartore / Photo Ark / Kanawha darters (Etheostoma kanawhae) pair, portrait, from the New River drainage, Virginia. Male top. Photographed at the Aquatic Wildlife Conservation Center, Virginia, USA. Captive.

Joel Sartore / Photo Ark / Sharpnose darter (Percina oxyrhynchus) male, portrait, from the New River drainage, Virginia. Photographed at the Aquatic Wildlife Conservation Center, Virginia, USA. Captive.

Joel Sartore / Photo Ark / Appalachia darter (Percina gymnocephala) male, portrait, from the New River drainage, Virginia. Photographed at the Aquatic Wildlife Conservation Center, Virginia, USA. Captive.

Joel Sartore / Photo Ark / Bibron's giant softshell turtle (Pelochelys bibroni) head portrait, Turtle Island, Austria. Captive, occurs in New Guinea.

Joel Sartore / Photo Ark / Bibron's giant softshell turtle (Pelochelys bibroni) portrait, Turtle Island in Graz, Austria. Captive, occurs in New Guinea.

Marie Read / Snow buntings (Plectrophenax nivalis) large flock in flight with American beech (Fagus grandifolia) saplings behind, Vermont, USA. January.

Marie Read / Pine grosbeak (Pinicola enucleator) male, perched on branch feeding on Ash (Fraxinus sp.) seeds in winter, Burlington, Vermont, USA. February.

Marie Read / Pine grosbeak (Pinicola enucleator) male, feeding on Spruce (Picea sp.) buds in late winter, Burlington, Vermont, USA. February.

Marie Read / Northern parula (Parula americana) male in breeding plumage, singing while perched on flowering Eastern redbud (Cercis canadensis) in spring, Ohio, USA. April.

Marie Read / Northern parula (Parula americana) male in breeding plumage, perched on branch singing in spring, Ohio, USA. April.

Marie Read / Northern parula (Parula americana) male in breeding plumage, perched on flowering Eastern redbud (Cercis canadensis) in spring, Ohio, USA. April.

Marie Read / Hooded warbler (Wilsonia citrina) male, perched on branch singing in spring, Ohio, USA. April.

Marie Read / Bobolink (Dolichonyx oryzivorus) male, in flight over Dandelion (Taraxacum sp.) flowers in a meadow, New York, USA. May.

Pal Hermansen / Topi (Damaliscus lunatus) female nuzzling newborn calf, Masai Mara, Kenya.

Pal Hermansen / Montezuma oropendulas (Psarocolius montezuma) pair, male feeding female during courtship, Costa Rica.

Tom Vierus / Tracking shot of coastline showing houses and yacht, surrounded by dense forest, near Kavieng, New Ireland, Papua New Guinea.

Tom Vierus / Aerial shot of a coastal community and adjacent ocean with visible coral reef pinnacles, Papua New Guinea.

Tom Vierus / Aerial shot of a coastal community on a thin strip of land, surrounded by sea and coral reef pinnacles. New Hanover, Papua New Guinea.