South Sudanese wrestlers take part in a wrestling match for peace in Juba on April 19, 2016. The last wrestling match for peace was held in Juba the day before civil war broke out in December 2013. (Photo by Carl de Souza/AFP Photo)

Tourists take a panoramic view of Kuala Lumpur from a skybox during a media preview at Kuala Lumpur Tower in Kuala Lumpur, Malaysia, 05 May 2016. Skybox, 421 metres above ground level will be the latest tourists attraction at Kuala Lumpur Tower, the 7th tallest freestanding tower in the world. (Photo by Ahmad Yusni/EPA)

“Hippo Chase”. As we approached the camp the Selinda Reserve of northern Botswana our boat passed by a hippo resting in the water. I turned around to look back at the boat's wake and saw the hippo charging after us! The hippo must've been tired from an all-nighter because he was angry. He rose way up out of the water three times trying to chase our boat! He was coming at us with such force that he created a wake of his own. Photo location: Selinda Reserve of northern Botswana. (Photo and caption by Curtis Simmons/National Geographic Photo Contest)

The moon illuminates the snow-covered Concordia, the confluence of the Baltoro and Godwin-Austen glaciers, near the world's second highest mountain the K2 (8,000 meters) in the Karakoram mountain range in Pakistan September 6, 2014. While other parts of Pakistan and northern India were flooded, Concordia in the Karakoram mountain range was covered with a seasonally unusual amount of snow. Geographically, Pakistan is a climbers paradise. It rivals Nepal for the number of peaks over 7,000 meters and is home to the world's second tallest mountain, K2, as well as four of the world's 14 summits higher than 8,000 meters. (Photo by Wolfgang Rattay/Reuters)

Diesel is poured into a container at theArea 10 shopping centre in Abuja, Nigeria May 25, 2015. Nigerian fuel marketers agreed to resume distribution on Monday after weeks of disruption led to chronic fuel shortages, bringing phone companies, banks and airlines to a standstill days before the inauguration of the country's new president. (Photo by Afolabi Sotunde/Reuters)

An Iranian man sells colorful ropes at the Tehrans old Bazaar, the place where the main economy trades take place, in Tehran, Iran, 25 January 2016. Reports state that Iranian officials expected the Iranian economy to grow on an average of eight percent over the coming five years following the lifting of sanctions against Iran. (Photo by Abedin Taherkenareh/EPA)

In this Thursday, March 17, 2016 photo, 33-year-old Palestinian clown doctor Alaa Miqdad, left, entertains 3-year-old patient Yaqin Shawaf, who suffers from dialysis, in the department of kidney diseases at Al-Rantisi children's hospital in Gaza City. (Photo by Adel Hana/AP Photo)

Is it a leaf? Is it tree bark? No, it’s the Satanic leaf-tailed gecko. Cleverly disguised as a rotting leaf, Madagascar’s camouflage king has red eyes, pointy horns and a taste for night hunting: it’s nature’s most devilish deceiver. The twisted body and veiny skin echo the detail of a dry leaf, which ensures the gecko blends in with its forest home. The mottled tail appears to have sections missing, as though it has withered over time. This mini-monster epitomises survival of the fittest, having adapted gradually to become today’s extraordinary leaf impersonator. (Photo by Thomas Marent/ARDEA)