Daniel J. Cox / Gray Wolf (Canis lupus) attacking female Elk (Cervus elaphus) crossing river, Alum Creek, Yellowstone National Park, Wyoming, sequence 2 of 4

Daniel J. Cox / Gray Wolf (Canis lupus) pair predating female Elk (Cervus elaphus) crossing river, Alum Creek, Yellowstone National Park, Wyoming, sequence 1 of 4

David Fleetham / Goby (Eviota sp) and juvenile porcelain crab (Pteroeides sp), on a Seapen. Komodo National Park, Indonesia.

Chien Lee / Harlequin Poison Dart Frog (Dendrobates histrionicus), Utria National Park, Colombia

Chien Lee / Red-headed Krait (Bungarus flaviceps) in rainforest, Santubong National Park, Sarawak, Borneo, Malaysia

Chien Lee / Golden Mantella (Mantella aurantiaca) in forest, Andasibe, Madagascar

Chien Lee / Golden Mantella (Mantella aurantiaca), Andasibe, Madagascar

Mark Raycroft / Elk (Cervus elaphus) bull in river in mist, North America

Mark Raycroft / Elk (Cervus elaphus) bulls fighting, North America

Alan Murphy/ BIA / Red-winged Blackbird (Agelaius phoeniceus) male, Texas

Alan Murphy/ BIA / Red-tailed Hawk (Buteo jamaicensis) flying, Texas

Donald M. Jones / Red-lored Parrot (Amazona autumnalis), Costa Rica