Participants climb over a wall at the “Tough Mudder” endurance event series in Arnsberg September 6, 2014. Competitors who took part in the endurance event saw themselves having to overcome various military style obstacles. (Photo by Ina Fassbender/Reuters)

Syrian refugees sit behind barbed wire as they wait to cross into Macedonia at the Greek-Macedonian border, near the village of Idomeni, August 21, 2015. (Photo by Yannis Behrakis/Reuters)

“Thunderstruck”. Summer stom. A super cell formed off the coast of New Zealand, intensified and swept across Christchurch and North Canterbury, February 23, 2014. Photo location: Christchurch, New Zealand. (Photo and caption by David Hardy/National Geographic Photo Contest)

A P-51 Mustang named “Charlotte's Chariot” from the Southern Heritage Air Foundation flies past a cloud of smoke and fire from a nearby battle reenactment during the Wings Over Houston Airshow in Houston, on Saturday, November 1, 2014. Battle reenactments are part of the yearly show held at Ellington Airport. (Photo by Kar Hlava/AP Photo/Bay Area Citizen)

“On Friday, after something of a show trial, three young women in a Russian punk band were found guilty and sentenced to two years in prison for an anti-Vladimir Putin protest in a Moscow cathedral earlier this year”. – Daniel Schwartz via CBC News

Photo: A woman wears on her chest the text “free p*ssy riot” as a demonstration by supporters of the jailed feminist punk band p*ssy Riot takes place outside the Russian Embassy on August 17, 2012 in London, England. The three women who staged an anti-Kremlin protest in a church in February, were found guilty today of hooliganism motivated by religious hatred, and could face a three-year jail sentence. Supporters are gathering in several cities around the world today as a mark of solidarity. (Photo by Dan Kitwood)

Tanzania, 1964. A touching moment between primatologist and National Geographic grantee Jane Goodall and young chimpanzee Flint at Tanzania's Gombe Stream Reserve. (Photo by Hugo van Lawick via National Geographic)

The sun bear (Ursus malayanus), also known as the honey bear, is a bear found primarily in the tropical rainforest (the dense lowland forests) in Southeast Asia; North-East India, Bangladesh, Myanmar, Thailand, Laos, Cambodia, Vietnam, Southern China, Peninsular Malaysia, and the islands of Sumatra and Borneo.

Iraqi teenagers swim in waste water from the nearby Tuweitha nuclear facility near Baghdad, Iraq on May 28, 2003. Iraqis are consuming contaminated water unaware of the dangerous pollutants that can cause severe ill health. (Photo by Damir Sagolj/Reuters)