A view of an installation as part of the “S.A.C.R.E.D” exhibition by Chinese artist Ai Weiwei during the 55th La Biennale of Venice, in the church of Sant'Antonin in Venice May 28, 2013. (Photo by Stefano Rellandini/Reuters)

Alpacas peek out of their box in Kielnarowa, Poland, June 11, 2014. A total of 35 female and 3 male alpacas were imported from Chile by the Rzeszow University of Information Technology and Management Center Zoo to be used for the therapy of children. Alpacas also provide one of the most expensive wools. (Photo by Darek Demanowicz/EPA)

A man holds his umbrella during snowfall on the Areopagitou pedestrian street beneath the Acropolis hill during snowfall in Athens, Greece, January 10, 2017. (Photo by Alkis Konstantinidis/Reuters)

Sheep walk as they are herded to summer pastures in Serra da Estrela, near Seia, Portugal June 27, 2015. In late June, shepherds young and old in the Seia region of central Portugal start guiding sheep, goats and cattle to the Serra da Estrela, the country’s highest mountains, in search of better pastures. There they stay until the end of September. Modern-day shepherds may have mobile phones to keep in touch with family and friends, but their lifestyle has changed little for centuries. The sound of cowbells and the bark of longhaired mastiffs starts early in the morning as the animals – often decorated with traditional woollen balls on their horns – are herded up steep, narrow paths. (Photo by Rafael Marchante/Reuters)

The view at night from the Shanghai Tower in Shanghai, China on August 7, 2015. The tower is technically smaller than the Burj Khalifa in Dubai but, while the observation deck of Dubai’s mega-structure is at 556m, the Shanghai Tower’s is at 561m, meaning the view is a little higher. (Photo by Paul Reiffer/REX Shutterstock)

Members of the Times Square Alliance snow clearing team take a photo on a snowbank at Times Square in the Manhattan borough of New York January 23, 2016. A winter storm dumped nearly 2 feet (58 cm) of snow on the suburbs of Washington, D.C., on Saturday before moving on to Philadelphia and New York, paralyzing road, rail and airline travel along the U.S. East Coast. (Photo by Shannon Stapleton/Reuters)

Self-employed pedicab driver Danilo Guerra, 25, uses his mobile phone as he waits for clients in downtown Havana April 12, 2016. (Photo by Alexandre Meneghini/Reuters)

Kurdish gunmen hold their rifles in front of the burning house of a Shi'ite militiaman during clashes in Tuz Khurmato, Iraq, April 24, 2016. (Photo by Goran Tomasevic/Reuters)