David Fleetham / Lemon shark (Negaprion brevirostris) viewed from below. West End, Grand Bahamas, Caribbean.

David Fleetham / White mouthed moray eel (Gymnothorax meleagris), Hawaii.

David Fleetham / Great white shark (Carcharodon carcharias) off Guadalupe Island, Mexico.

David Fleetham / Great white shark (Carcharodon carcharias), portrait. Guadalupe Island, Mexico.

Alex Mustard / American crocodile (Crocodylus acutus) reflected in the surface as it floats, Jardines de la Reina, Gardens of the Queen National Park, Cuba. Caribbean Sea.

Ingo Arndt / Mountain gorilla (Gorilla gorilla berengei) yawning, showing stained teeth, Parc des Volcans, Rwanda

Francois Savigny / Chinese tiger {Panthera tigris amoyensis} chewing & scratching tree bark to clean claws & teeth. Meuachan Mountains, China, captive.

Francois Savigny / Spectacled caiman {Caiman crocodilus} jaw and teeth close-up. Llanos, Venezuela, S. America

Ingo Arndt / Hamadryas baboon male threat display {Papio hamadryas} Africa

Ingo Arndt / Gelada baboon males threat display {Theropithecus gelada} Simien Mt NP, Ethiopia

Ingo Arndt / Gelada baboon male threat display {Theropithecus gelada} Simien Mt NP, Ethiopia

Claudio Contreras / American crocodile (Crocodylus acutus) split level with animal resting at surface in shallow water over seagrass bed, Banco Chinchorro Biosphere Reserve, Caribbean region, Mexico