Shepherds walk with sheep through the village on their way home during autumn redyk in Gron, Tatra Mountains region of southern Poland, October 6, 2015. Redyk is a traditional, kilometres-long march of highlanders with flocks of sheep, which takes place twice a year: in the spring at the start of the grazing season, and in the autumn at season's end. (Photo by Kacper Pempel/Reuters)

In this May 14, 2016 photo, children wearing their school backpacks climb on a cliff using a bamboo ladder on their way home from school in Zhaojue county, southwest China's Sichuan province. A village in China's mountainous west where schoolchildren must climb an 800-meter (2,625-foot)-high bamboo ladder secured to a sheer cliff face may get a set of steel stairs to improve it's safety. (Photo by Chinatopix via AP Photo)

A man driving a vintage car reacts as he passes by crabs crossing a highway on their way to spawn in the sea in Playa Giron, Cuba on April 25, 2017. Each year, after the first spring rains, millions of red, yellow and black landcrabs march for days from the surrounding forests to the bay on Cuba's southern coast to spawn in the sea. (Photo by Alexandre Meneghini/Reuters)

A group of Japanese schoolgirls marching in formation during a school visit to the third regiment to experience the soldier's way of life. (Photo by Fox Photos/Getty Images). Circa 1938

Wai Ching Jason Poon of Hong Kong competes in the Men's 1m Springboard preliminary round during Day One of the 14th FINA World Championships at the Oriental Sports Center on July 16, 2011 in Shanghai, China. (Photo by Feng Li/Getty Images)

Onati Basque dancers go airborne as they perform Basque traditional dances while making their way to the front of Saint Mark's Catholic Church, Saturday, August 1, 2015, in Boise, Idaho. The annual Mass, conducted in English and Basque, was held at the church for the first time. (Photo by Kyle Green/Idaho Statesman via AP Photo)

“Artist Paula Swisher has come up with a quirky way of lessening the stress of household bills - by doodling highly intricate birds on each one. Swisher, 37, has drawn hundreds of birds in her lifetime and puts her love of ornithology down to the nature walks she went on as a youngster. Looking for work during the recession, she began sketching birds on the inside of books, seeing the practice as a creative way to mutate the pages into something fresh. But now she's made the transition from books to bills – while admittedly making a playful commentary on the predatory banking businesses”. – Caters News. (Photo by Paula Swisher/Caters News)

Militants loyal to Yemen's exiled government ride on the back of a pick-up truck in the country's central city of Taiz August 19, 2015. Militia forces loyal to Yemen's exiled government fought their way deep into the central city of Taiz this week, local officials said, largely pushing out Houthi militiamen from the country's third largest city. (Photo by Reuters/Stringer)