Artist Kong Ning wears a wedding dress made from respirators to highlight concerns about air quality and pollution in Beijing, China on December 1, 2015. (Photo by Luo Xiaoguang/Xinhua Press/Corbis)

A Chinese man wears a mask to protect against pollution as he waits at a red light while commuting to work in heavy smog on December 8, 2015 in Beijing, China. The Beijing government issued a 'red alert' for the first time since new standards were introduced earlier this year as the city and many parts of northern China were shrouded in heavy pollution. Levels of PM 2.5, considered the most hazardous, crossed 400 units in Beijing, lower than last week, but still nearly 20 times the acceptable standard set by the World Health Organization. The governments of more than 190 countries are meeting in Paris to set targets on reducing carbon emissions in an attempt to forge a new global agreement on climate change. (Photo by Kevin Frayer/Getty Images)

A woman carries a piglet as she runs on ice during a running challenge in Changsha, Hunan province February 8, 2015. A total of 20 people participated in the challenge requiring them to choose a pig ranging between 15 kg and 115 kg in weight, and carrying it while running on a 20.15-metre-long ice track. The participants that complete the challenge will be rewarded with the pig they carried, local media reported. (Photo by Darwin Zhou/Reuters)

People take pictures with their mobile phone of a scale model of a dinosaur displayed in front of La Sapienza University headquarters in Rome April 10, 2015. The realistic reproductions of dinosaurs are part of the “Dinosaurs in the flesh, science and art bring to life the rulers of a lost world” exhibition. (Photo by Alessandro Bianchi/Reuters)

A donkey savors warming temperatures after a long winter at the zoo in Warsaw, Poland, on Wednesday, April 8, 2015. (Photo by Czarek Sokolowski/AP Photo)

Mercedes Formula One driver Lewis Hamilton of Britain sprays champagne at a grid girl as he celebrates his victory on the podium after the Chinese F1 Grand Prix at the Shanghai International Circuit, April 12, 2015. (Photo by Carlos Barria/Reuters)

Undated handout photo of Buckbeak, a Hippogriff that lived with Rubeus Hagrid in the Harry Potter series, has his feathers preened and replenished by featherologist Val Jones, as he will feature in the the Feathers and Flight event at Warner Bros. Studio Tour London. This is the first make-over Buckbeak has received since the hugely popular Harry Potter film series was made. His intricate coat is created from thousands of individually airbrushed chicken and goose feathers that Val will carefully clean and replenish in time for the start of Feathers and Flight. Val will lead an expert team to demonstrate the techniques that made winged wonders such as Buckbeak and Fawkes the Phoenix a reality on screen. (Photo by Tim Anderson/PA Wire)

A Snowboarder participates in a waterslide contest, which consists of gliding over a water pool embedded in snow, during the closing event of the ski resort of Nendaz, southwestern Switzerland, Monday, April 21, 2014. (Photo by Maxime Schmid/AP Photo/Keystone)