A police officer gives instructions to migrants rushing to board a train that would take them towards Serbia, at the railway station in the southern Macedonian town of Gevgelija, Wednesday, August 20, 2015. Macedonian police stepped up the security at the border with Greece apparently trying to stem recent surge of migrants who are coming from Greece. (Photo by Darko Vojinovic/AP Photo)

Alex Plunkett, left, and Sean Hart, both of Arlington, Va., join hundreds participating in the annual International Pillow Fight Day on April 5. Massive pillow fights broke out on the Mall in Washington and in cities around the world. (Photo by Marvin Joseph/The Washington Post)

A love story with two log choppers. “In 1993, I was working on a project about life in the Olomouc region of Czechoslovakia. One day, I came to the village of Dlouhá Loučka-Křivá and went into a courtyard where I saw two old people, a husband and wife, sawing firewood for winter. They were working quietly, concentrating. I watched them fetch a beam from a wrecked barn, but they didn’t discuss how they planned to carry it to the saw. The woman faced one way, the man the other. When they realised, the woman eventually turned and followed her husband. The picture I took is the picture of many relationships – when each partner wants something different, but they have to come to an agreement, pull together eventually”. (Photo by Jindrich Streit)

A boy and a woman run across a railway track as a train approaches in Chengdu, Sichuan province, China, October 8, 2015. Many residents disregard sign prohibiting this kind of illegal crossing and choose to do so to save time, local media reported. (Photo by Hao Fei/Reuters/Western China Metropolis Daily)

“Tasty Nature” by Dipesh Bhatt. “The blue banded bee (Amegilla cingulata) is pointing this sheath towards the flowers in preparation for sipping nectar”. Taken in Gujarat, India. (Photo by Dipesh Bhatt/2016 Royal Society of Biology Photographer of the Year competition)

Bikini-clad women ski as they are led by a car during a performance on the frozen Yenisei River outside Krasnoyarsk, Siberia, Russia, March 20, 2016. The performance, entitled “Siberian Spring's Strings” and created with the participation of artist Vasily Slonov, marked the day of spring equinox (vernal equinox), according to organizers. (Photo by Ilya Naymushin/Reuters)

Galapagos – Rocking the Cradle: Four major ocean currents converge along the Galapagos archipelago, creating the conditions for an extraordinary diversity of animal life, April 25, 2016. The islands are home to at least 7,000 flora and fauna species, of which 97 percent of the reptiles, 80 percent of the land birds, 50 percent of the insects and 30 percent of the plants are endemic. (Photo by Thomas P. Peschak for National Geographic/World Press Photo)

Islamic female students practice the ancient Thai art of “Krabi Krabong” taught as a sport at the Darunsat Wittaya school on August 16, 2011 in Saraburi, Thailand. (Photo by Paula Bronstein/Getty Images)