Jussi Murtosaari / Common goldeneye (Bucephala clangula) male in flight. Tervatehdas, Finland. April.

Jussi Murtosaari / Common goldeneye (Bucephala clangula) male on water amongst ice. Tervatehdas, Finland. April.

Charlie Summers / Common goldeneye (Bucephala clangula) drake flies low over the South Platte River, Littleton, Colorado, USA. January.

Fabrice Cahez / Common goldeneye (Bucephala clangula) Bay of Somme, France, February.

Marie Read / Buffleheads (Bucephala albeola), courtship flight in which several males chase a female (fourth from left) at high speed through the air, early spring, Aurora, New York, USA. Digitally manipulated rig...

Bryan and Cherry Alexander / Nadia Takui, a Chukchi girl, dressed in a traditional reindeer skin Kerker, (knee length coverall) sitting at the edge of the polog (sleeping area) in a Yaranga (tent) at a reindeer herders' summer ca...

Bryan and Cherry Alexander / Vera Rakhtuvia, a Chukchi woman, relaxes by candlelight with her granddaughter, Susha, in the polog (sleeping area) inside the family's Yaranga (tent) at their summer camp. Iultinsky District, Chukotk...

Bryan and Cherry Alexander / After waking up in the morning, Yaroslava Votgyrgina, a Chukchi girl, sticks her head out of the polog (sleeping area) in a Yaranga (tent) at a reindeer herders' summer camp. Iultinsky District, Chuko...

Bryan and Cherry Alexander / Nadia Takui, a Chukchi girl, dressed in a traditional reindeer skin Kamleika (parka) reads a magazine at the front of the polog (sleeping area) in a Yaranga (tent) at a reindeer herders' summer camp....

Bryan and Cherry Alexander / Nadia Takui, a Chukchi girl, dressed in a traditional reindeer skin Kamleika (parka) sits by the by the front of the polog (sleeping area) in a Yaranga (tent) at a reindeer herders' summer camp. Iulti...

Bryan and Cherry Alexander / Chukchi reindeer herder dressing in traditional reindeer skin clothing inside the polog (inner tent) of his Yaranga (traditional tent). Chukotskiy Peninsula, Chukotka, Siberia, Russia, 2010