People manoeuvre into position as they take part in a mass nude art installation entitled Sea of Hull by New York based artist Spencer Tunick in Hull, England, Saturday July 9, 2016. (Photo by Danny Lawson/PA Wire via AP Photo)

Situated 10km outside Nairobi city centre, this private giraffe sanctuary is centred around a colonial manor house named Giraffe Manor. Living within the grounds is a herd of rare Rothschild giraffe. The giraffes visit twice a day searching for food, before returning to the forest. Although still wild animals, they have become accustomed to receiving treats from residents and guests. (Photo by Klaus Thymann)

A polar bear plays with a pylon during celebrations marking its first birthday in an enclosure at Tierpark Hellabrunn zoo in Munich December 9, 2014. (Photo by Michaela Rehle/Reuters)

A panda bear sits on a logs in a zoo on January 15, 2015 in Hangzhou, China. (Photo by Feature China/Barcroft Media)

A passenger plane comes into land over a field containing horses at Heathrow Airport on August 11, 2014 in London, England. Heathrow is the busiest airport in the United Kingdom and the third busiest in the world. The airport's operator BAA wants to build a third runway to cope with increased demand. (Photo by Peter Macdiarmid/Getty Images)

A boy runs past one of the exhibits during the Dinosaurs exhibition in Belgrade, Serbia, Thursday, August 21, 2014. “Dino Park” has opened at Belgrade's Kalemegdan Fortress. (Photo by Darko Vojinovic/AP Photo)

A person tries to extinguish flames as sparks fly during a wild forest fire in Valparaiso, Chile, Sunday April 13, 2014. Authorities say the fires have destroyed hundreds of homes, forced the evacuation of thousands and claimed the lives of at least seven people. (Photo by Luis Hidalgo/AP Photo)

Participants take part in an extreme run “Bison race” near the town of Logoisk, Belarus September 17, 2016. (Photo by Vasily Fedosenko/Reuters)