A rainbow appears over the Louisiana gulf May 26, 2010 in the Gulf of Mexico near Brush Island, Louisiana. (Photo by Win McNamee/Getty Images)

A participant runs on stairs during a vertical run event at China World Summit Wing hotel in Beijing, China, September 19, 2015. About 800 runners took part in the event on Saturday, which takes runners up 82 floors, covering a total of 2,041 steps to a height of 330 metres, the organizer said. (Photo by Kim Kyung-Hoon/Reuters)

Models get ready before hitting the catwalk at the French Ministry of Culture during the dwarf fashion show in Paris, France, Friday October 2, 2015. The show is an event organizers say is aimed at highlighting the elitism and prejudice that the model industry encourages in its depiction of bodies. It is presented during the Paris Fashion Week but is not part of it. (Photo by Jerome Delay/AP Photo)

Army soldiers prepare a military elephant for the parade during a rehearsal for Sri Lanka's 68th Independence day celebrations in Colombo, February 2, 2016. (Photo by Dinuka Liyanawatte/Reuters)

Runners wearing full solid-coloured bodysuits take part in a marathon in Tel Aviv, Israel February 26, 2016. Tens of thousands took part in the event, which saw streets closed off from Rokach Boulevard in the north to Jaffa’s Jerusalem Boulevard in the south. Other than the main 42-kilometer (26-mile) run, the day’s events also included a half-marathon route, several shorter circuits, a handcycle race for the handicapped and a mini-marathon for kids of a single kilometer (0.6 miles). (Photo by Amir Cohen/Reuters)

Children play at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, March 29, 2016. (Photo by Marko Djurica/Reuters)

This strange coral-looking specimen is actually a mushroom. The photo, “Beautiful Destroyer”, was taken in the Panamanian tropical rainforest where the mushroom produces nitrogen, an element vital to soil health. (Photo by Sarah A. Batterman)

This greedy piglet was isolated from the rest of its litter by the farmer who named it Hitler after it tried to grab all the food at feeding time. (Photo by R J Lewis/Getty Images). 1942