Jack Dykinga / Yellow-headed blackbirds (Xanthocephalus xanthocephalus) and Redwing blackbirds (Agelaius phoeniceus) roosting. Whitewater Draw Wildlife Area, Arizona, USA, December.

Jack Dykinga / Murmuration of Yellow-headed blackbirds (Xanthocephalus xanthocephalus) and Redwing blackbirds (Agelaius phoeniceus) at sunset, before roosting. Whitewater Draw Wildlife Area, Arizona, USA, December.

Suzi Eszterhas / Cotton-top tamarin (Saguinus oedipus), three climbing tree. Northern Colombia.

Suzi Eszterhas / Cotton-top tamarin (Saguinus oedipus), adult with two week old baby on back. Northern Colombia.

Claudio Contreras / Central American spider monkey (Ateles geoffroyi) juveniles hanging by tails and playing, Calakmul Biosphere Reserve, Yucatan Peninsula, Mexico, August

Jeff Foott / Yacare caiman (Caiman yacare) with butterfly on snout, Cuiaba River, Pantanal Matogrossense National Park, Pantanal, Brazil.

Jeff Foott / Wild California condor (Gymnogyps californianus) near San Pedro Martir National Park, Northern Baja California, Mexico.

Chien Lee / Waigeo Spotted Cuscus (Spilocuscus papuensis), Waigeo, West Papua, Indonesia

Andy Trowbridge / Kea (Nestor notabilis) juvenile in flight. Arthur's Pass National Park, South Island, New Zealand. Endangered Species.

Richard Robinson / False killer whales (Pseudorca crassidens) traveling with a pod of pelagic Bottlenose dolphins (Tursiops truncatus) Northern New Zealand

Richard Robinson / False killer whales (Pseudorca crassidens) travelling with a pod of pelagic Bottlenose dolphins (Tursiops truncatus) Northern New Zealand Editorial use only.

Chien Lee / Borneo Opposite-fingered Tree Frog (Chiromantis inexpectatus), new species, Maliau Basin, Sabah, Malaysia