Afghan dogs fight during the weekly dog fight in Kabul, Afghanistan, 17 February 2017. Under the Taliban dog fighting was forbidden, but since their fall it has become a major source of entertainment for hundreds of Afghans, where bets can amount to thousands of dollars and the dogs, which must be over one year old, are well-cared for by their owners and fed milk, butter and meat. (Photo by Hedayatullah Amid/EPA)

Actors dressed as a “Yeti” attend a promotional event for Travel Channel's “Expedition Unknown: Hunt for the Yeti” in Manhattan, New York City, U.S., October 4, 2016. (Photo by Brendan McDermid/Reuters)

An Indian woman dressed as Hindu Goddess Kali participates in a “Shivratri” procession in Allahabad, India, Thursday, Feb. 27, 2014. “Shivaratri”, or the night of Shiva, is dedicated to the worship of Lord Shiva, the Hindu god of death and destruction. (Photo by Rajesh Kumar SinghAP Photo)

Actress Frederique Bel attends the Opening ceremony and the “Grace of Monaco” Premiere during the 67th Annual Cannes Film Festival on May 14, 2014 in Cannes, France. (Photo by Pascal Le Segretain/Getty Images)

Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)

NASA's DHC-3 Otter plane flies in Operation IceBridge-Alaska surveys of mountain glaciers in Alaska in this image released on September 18, 2014. Over the past few decades, average global temperatures have been on the rise, and this warming is happening two to three times faster in the Arctic. (Photo by Chris Larsen/Reuters/NASA/University of Alaska-Fairbanks)

Festival goers dance during Glastonbury Festival at Worthy Farm, near Pilton, Somerset, Britain, 23 June 2017. The outdoor festival runs from 21 to 25 June. (Photo by Nigel Roddis/EPA)

The Sugar Plum Fairy, Katherine Free, left, dances with the dog, Pig, during the Birmingham's Ballet “Mutt-cracker”, a rendition of the famous ballet “The Nutcracker”, in Birmingham, Alabama, December 8, 2016. (Photo by Brynn Anderson/AP Photo)