Bison along the Bitterroot Valley's Eastside Highway north of Stevensville, Montana, are covered in snow following a blizzard on November 23, 2010. (Photo by Perry Backus/The Missoulian)

Cheng Chen (R), a 27-year-old worker at a state-owned enterprise, poses for a photograph with his nephew who is wearing his home-made Iron Man armour, in Xuzhou, Jiangsu province April 13, 2015. It cost Cheng about 500 yuan ($81 USD) to make the armour, which weighs about 4 kilograms, with plastic boards and LED lights, local media reported. (Photo by Reuters/Stringer)

A prototype battery-powered plane, called Greased Lightning or GL-10 is pictured flying at NASA's Langley Research Center in this undated handout photo obtained by Reuters May 1, 2015. The plane, which has 10 engines and can take off like a helicopter and fly efficiently like an aircraft, is currently in the design and testing phase. (Photo by Reuters/NASA)

A commuter gestures to Boris Johnson as he rides across Vauxhall Bridge in London, England on November 19, 2015. The London mayor was opening a cycle superhighway. (Photo by John Stillwell/PA Wire)

A member of a local swimming club holds a Russian national flag as he dives in at the start of a 24-hour swimming marathon near the western Siberian city of Barnaul March 29, 2014. Thirty members of the club will swim in turn during the event, held to mark Crimea becoming part of Russia, local media reported. (Photo by Andrei Kasprishin/Reuters)

“Attacking Howler Monkey”. Due to a major tropical rainstorm my wife and I were forced to stay overnight in a Howler Monkey Rescue center in Panama. I used the time to explore the area and to take photos of the monkeys. Just after the rain finally stopped, I ran into this monkey that tried to mock attack me. I quickly took a couple of photos before retreating to a (more) safe distance. (Photo and caption by Christian Mueller-Planitz/National Geographic Traveler 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.

A woman spits red paint as if it is blood protesting against bullfights in Madrid, Spain on March 27, 2016. Anti-bullfighting protesters have turn the iconic square of “Puerta del Sol” into a bullring. Protesters, almost naked covered with red paint as if it was blood, have demanded the abolition of bullfights under the slogan “The bull suffers!”. (Photo by Marcos del Mazo/Pacific Press)

Party-goers partake in a festival better known as Holi One, during International Workers Day in Johannesburg, South Africa, 01 May 2015. The colour festival promotes togetherness as well as colourness in everday life. May Day is observed worldwide every year on 01 May. (Photo by Kevin Sutherland/EPA)