An Afghan National Army (ANA) soldier assigned to the Mobile Strike Force Kandak fires a RPG-7 rocket-propelled grenade launcher during a live-fire exercise supervised by the Marines with the Mobile Strike Force Advisor Team on Camp Shorabak, Helmand province, Afghanistan, May 20, 2013. The Marines with the Mobile Strike Force Advisor Team instructed and mentored their ANA counterparts on how to properly utilize their weapons systems. (Photo by SSgt Ezekiel R. Kitandwe/RCT 7)

Belgium supporters pose before the World Cup quarterfinal soccer match between Argentina and Belgium at the Estadio Nacional in Brasilia, Brazil, Saturday, July 5, 2014. (Photo by Victor R. Caivano/AP Photo)

Common seals are reintroduced to the wild on the beach of the island Juist, Germany, 28 July 2014. It is the first reintroduction to the wild drive of the seal breading station Norddeich this year. (Photo by Carmen Jaspersen/EPA)

Participants hang from ropes as they learn how to use safety gears at an experience centre for construction safety training in Beijing, September 5, 2014. The centre which opened in June 2014 was established to educate workers about construction safety. According to the centre, about 1,000 construction workers undergo 3-hour classes which comprises of 33 modules every month. (Photo by Kim Kyung-Hoon/Reuters)

(L-R) Poppy Delevingne, Model of the Year Cara Delevingne, Joan Smalls and Karlie Kloss pose in the winners room at the British Fashion Awards at London Coliseum on December 1, 2014 in London, England. (Photo by Pascal Le Segretain/Getty Images)

A frog sits on a leaf and instead of seeing a reflection of itself in the water below, it sees a snail, attached to the bottom of the leaf, in a fish tank in Vietnam. (Photo by Duong Quoc Dinh/Solent Ne/SIPA Press)

A participant prepares for the Red Bull Air Race World Championships in Abu Dhabi, United Arab Emirates on February 6, 2017. (Photo by Red Bull Content Pool/SIPA Press/Rex Features/Shutterstock)

Five year old George holds an orange to feed the Owl butterflies at the Natural History Museum in London, Thursday, March 30, 2017. Hundreds of tropical butterflies were released to launch the Natural History Museum's Sensational Butterflies exhibition, starting for the public on March 31, 2017. (Photo by Frank Augstein/AP Photo)