In this photo taken on Thursday, July 23, 2015 migrants enter a train to Serbia at the railway station in the southern Macedonian town of Gevgelija. The country has become a major transit route for thousands of Middle Eastern and African refugees and migrants who cross over from Greece and then continue into Serbia. (Photo by Boris Grdanoski/AP Photo)

Houthi followers perform the traditional Baraa dance ahead of a demonstration against the Saudi-led air strikes in Yemen's capital Sanaa August 24, 2015. The nothern-based Houthis, a Shi'ite Muslim group, took control of Sanaa last September. Arab countries intervened in the conflict in March to halt a Houthi advance into the south which caused the Saudi-backed government to flee to Riyadh from its refuge in the southern port of Aden. (Photo by Khaled Abdullah/Reuters)

A Thai veterinarian takes a picture of a 2-year-old orangutan during a health examination at Kao Pratubchang Conservation Centre in Ratchaburi, Thailand, August 27, 2015. Thai veterinarians from the Department of National Park Wildlife, and Plant Conservation conducted a health check of 14 orangutans for preparation for the repatriation to their country of origin, Indonesia. (Photo by Athit Perawongmetha/Reuters)

A firefighter recovers after climbing the 1800 steps of the Costanera Centre Tower as part of the “Race for Life” aimed at encouraging organ donation in Chile, in Santiago, on October 16, 2016. More than 500 volunteer firefighters are expected to climb the 1800 steps of the tallest building in South America to promote and encourage organ donation in the country. (Photo by Claudio Reyes/AFP Photo)

Afghanistan, published by Taschen later July, is a retrospective portfolio of the Magnum photographer Steve McCurry’s most striking images of the country, from 1979 to 2016. Here: Kunar province, 1980. Armed mujahideen carry animal skins to use as inflatable buoys to cross rapids. (Photo by Steve McCurry/Taschen/Magnum Photos/The Guardian)

As an American in 1990s Cuba, Tria Giovan risked being branded a traitor. But the photographer continued to visit and, from the dance hall to the hair salon, she captured the resilient spirit of the Cuban people. The 120 images in Tria Giovan’s “The Cuba Archive” are from the period in the 90s when, as an American, travel to Cuba could have seen her branded a traitor, as the country was subject to a US trade embargo. Her trip required lots of planning – and patience. (Photo by Tria Giovan/The Guardian)

A competition, now in its 43rd year, dedicated to showcasing the beautiful and bizarre as seen under a light microscope attracted over 2,000 entries from 88 countries. Here: Honorable Mention by Emre Can Alagöz, Istanbul, Turkey: The eyes of a jumping spider, magnified 6x. (Photo by Emre Can Alagöz/2017 Nikon Small World Photomicrography Competition)

Nguyen Thi Vui paddles her boat in the flooded streets of Hoi An, Vietnam, Monday, November 6, 2017. A powerful typhoon that rocked Vietnam has killed dozens of people and caused extensive damage to the country's south-central region ahead of the APEC summit that will draw leaders from around the world, the government said Monday. (Photo by Hau Dinh/AP Photo)