In this Thursday, December 1, 2016 photo, Cat Bigney, part of the Oglala Native American tribe, waits on the shore of the Cannonball river for travelers to arrive by canoe at the Oceti Sakowin camp where people have gathered to protest the Dakota Access oil pipeline in Cannon Ball, N.D. So far, those at the camp have shrugged off the heavy snow, icy winds and frigid temperatures. But if they defy next week's government deadline to abandon the camp, demonstrators know the real deep freeze lies ahead. Life-threatening wind chills and towering snow drifts could mean the greatest challenge is simple survival. (Photo by David Goldman/AP Photo)

Second placed Kalex Moto2 Tito Rabat (rear R) of Spain and third placed Kalex Moto2 Alex Rins of Spain spray with champagne during the award ceremony for the Czech Grand Prix in Brno, Czech Republic, August 16, 2015. (Photo by David W. Cerny/Reuters)

A racegoer uses the camera on her phone to check her hair on the opening day of the Grand National Festival at Aintree Racecourse on April 3, 2014 in Aintree, England. The three days of racing attracts thousands of racegoers and fans from across the world. The meeting culminates with millions of pounds being wagered on the runners taking part in Europe's richest jump race, the Grand National. (Photo by Christopher Furlong/Getty Images)

“The Sunsetter”. An EF-4 tornado rips through the open space of farmland near Rozel, Kansas. This tornado moves slowly but powerful towards the setting sun an gets its beautiful color right before sunset. Storm Chasers are spotting on the left side. Photo location: Rozel, Kansas. (Photo and caption by Dennis Oswald/National Geographic Photo Contest)

ATTENTION! All pictures are presented in high resolution. To see Hi-Res images – just TWICE click on any picture. In other words, click small picture – opens the BIG picture. Click BIG picture – opens VERY BIG picture.

Tourists kissing front of Malaysia's landmark Petronas Twin Towers with lights on before turned off to mark Earth Hour 2016 in Kuala Lumpur, Malaysia, 19 March 2016. Earth Hour takes place worldwide at 8.30 p.m. local time and is a global call to turn off lights for 60 minutes to raise awareness of the danger of global climatic change (Photo by Fazry Ismail/EPA)

Enjoying a tickle from her keeper, an orphaned orangutan at the SOCP Quarantine Centre in Sumatra, Indonesia on March 20, 2016. The island’s orangutan population has been devastated in recent years as the forest areas are destroyed to make way for palm oil plantations. (Photo by Jami Tarris/Barcroft Media)

A member of the “Morenada Los Cocanis” group dances during the Carnival parade in Oruro February 14, 2015. Thousands of dancers and tourists attend the carnival celebrations in Oruro, south of La Paz. (Photo by David Mercado/Reuters)

A man is silhouetted in front of the Allianz-Arena as he walks his dogs at sunrise in Munich, southern Germany, Friday, April 10, 2015. (Photo by Peter Kneffel/AP Photo/DPA)