A walruses at Hagenbeck Zoo in Hamburg, Germany on July, 7, 2015. (Photo by Werner Struss/Startraks action)

A man makes a mud oven to be used for baking bread at a workshop in Najaf, south of Baghdad, July 23, 2015. (Photo by Alaa Al-Marjani/Reuters)

Girls ride on a donkey cart with grass for animals on the outside of Nangarhar province, Afghanistan May 19, 2015. (Photo by Reuters/Parwiz)

Competitors release their hens during the World Championship Hen Racing Championships in Bonsall, Britain August 1, 2015. (Photo by Darren Staples/Reuters)

An incredible clear-air lightning display from storms to the east of Noonamah, just outside Darwin on April 6, 2015. (Photo by Jacci Ingham/The Guardian)

Children play in front of a brick factory on the outskirts of the northern Myanmar city of Mandalay on December 14, 2015. (Photo by Phyo Hein Kyaw/AFP Photo)

Singer Karima Charni walks the runway during the Chocolate fashion show as a part of the Salon Du Chocolat 2015 – Chocolate Fair at Parc des Expositions Porte de Versailles on October 27, 2015 in Paris, France. (Photo by Kay-Paris Fernandes/WireImage)

A model presents a creation by designers Humberto Leon and Carol Lim as part of their Autumn/Winter 2015/2016 women's ready-to-wear collection for Japanese fashion house Kenzo during Paris Fashion Week March 8, 2015. (Photo by Gonzalo Fuentes/Reuters)