An employee collects eggs from inside a dead female sturgeon at the caviar fish farming company “Sturgeon”, the leading French producer, in Saint-Genis-de-Saintonge, France, November 8, 2016. (Photo by Regis Duvignau/Reuters)

Purev and Buyantogtokh enjoy the warmth of the fire in the snow in Altai Mountains, Mongolia, September 2016. Navigate the snowy wilds of Mongolia with this nomadic reindeer herding family. Photographer Joel Santos dived 1000km into the depths of Northern Mongolia to visit the Ganbaa family near Khovsgol Lake. (Photo by Joel Santos/Barcroft Images)

Mom dressed as Santa and a boy dressed as Santa's helper posing under the water in the pool on December 15, 2016 in Odessa, Ukraine. (Photo by Andrey Nekrasov/Barcroft Images)

A woman takes part in a four-minute flash mob pillow fight at the Old Town Square in Prague, Czech Republic, December 22, 2016. (Photo by David W. Cerny/Reuters)

A Palestinian protester, dressed as Santa Claus, reacts after inhaling tear gas fired by Israeli troops during clashes in the West Bank city of Bethlehem December 23, 2016. (Photo by Mussa Qawasma/Reuters)

In this photo taken Friday, December 9, 2016, young ballerinas practice under the instruction of Kenyan ballet dancer Joel Kioko, 16, in a room at a school in the Kibera slum of Nairobi, Kenya. (Photo by Ben Curtis/AP Photo)

Santi Diaz Mosquera, 41, a “percebeiro” (barnacle fisherman), collects barnacles on rocks on the coast of Ferrol, in the northwestern Spanish region of Galicia, December 15, 2016. (Photo by Nacho Doce/Reuters)