Wakhi nomad women milk yaks in Wakhan, Afghanistan. About 12,000 villagers live at an altitude of 4,500 metres in the harsh, desolate terrain. The Wakhi people live a simple, relaxed life with their livestock. (Photo by Eric Lafforgue/Barcroft Images)

People watch a crocodile with a used motorcycle tyre around its neck on a river in Palu, Central Sulawesi province, Indonesia September 20, 2016 in this picture taken by Antara Foto. Residents suspect the tyre was garbage thrown into the river before it became trapped around the crocodile's neck, reported Antara. (Photo by Mohamad Hamzah/Reuters/Antara Foto)

Storm erupts over Pacific Ocean as plane zooms past at 37,000 ft. The amazing picture shows a massive cloud erupting against a starry night sky as the off-duty airman Santiago Borja flew over the Pacific near Panama City. He had just moments to take the breathtaking snap as the Boeing 767 zoomed by at 37,000 ft on its way from North America to Ecuador. He also had take the picture perfectly in time with the flash of lightning to capture the storm in all its glory. (Photo by Santiago Borja/Solent News)

The moon rises behind the skyline and financial district in Toronto, November 25, 2015. (Photo by Mark Blinch/Reuters)

A woman walks past a caricature of Britain's Foreign Secretary Boris Johnson in east London, Britain November 18, 2016. (Photo by Andrew Winning/Reuters)

In this September 10, 1977, file photo, from left, Hua Guofeng, Chinese Communist Party (CCP) chairman and Mao Zedong's immediate successor; Ye Jianying, CCP vice chairman and future ceremonial head of state; Deng Xiaoping, no formal titles at the time but soon to emerge as paramount leader during the reform era; Li Xiannian, CCP vice chairman and future president; Wang Dongxing, head of the leadership bodyguard unit who helped topple the Gang of Four, view the body of later Chinese leader Mao Zedong in Beijing. (Photo via AP Photo)

A man talks on his mobile phone in the village of Devmali in the desert state of Rajasthan, India June 14, 2016. (Photo by Himanshu Sharma/Reuters)

A hippopotamus performs during a show at the circus in Krasnoyarsk, Siberia, Russia, July 7, 2016. (Photo by Ilya Naymushin/Reuters)