A Filipino flagellant crawls along a street on Maundy Thursday, in San Fernando city, Pampanga Province, north of Manila, Philippines, 24 March 2016. Many Filipino Catholic penitents mark the Holy Week by submitting to different forms of physical penance in the hopes of being forgiven for their sins. (Photo by Francis R. Malasig/EPA)

Fighters of the pro-government Popular Resistance Committees militia carry a cannon as they transport it in parts to Yemen's southwestern war-torn city of Taiz December 26, 2015. (Photo by Reuters/Stringer)

People crowd together in an attempt to buy chickens at a Mega-Mercal, a subsidized state-run street market, in Caracas January 24, 2015. President Nicolas Maduro shook up complex currency controls on Wednesday and also prepared Venezuelans for a rise in the world's cheapest fuel prices in response to a recession worsened by plunging oil revenue. The socialist-run OPEC member's economy shrank 2.8 percent in 2014 while inflation topped 64 percent, the socialist leader announced in a speech to parliament, in what is almost certainly the worst performance in Latin America. (Photo by Carlos Garcia Rawlins/Reuters)

Activists protesting cuts in subsidies to solar power in Germany protest outside the building where Vice Chancellor and Economy Minister Philipp Roesler and Environment Minister Norbert Roettgen were announcing the cuts on February 23, 2012 in Berlin, Germany. (Photo by Sean Gallup/Getty Images)

A male puma, named Bordo arrives for an examination and tests at a veterinary in Brasilia, Brazil, 31 October 2017 (issued 01 November 2017). Bordo, a young male puma, captured when he was a cub, will become the first animal of his species to be released in a sanctuary in the Brazilian savannah in Goias State close to Brasilia. The sanctuary, a preserve for wild cats, is in the first phase and is located on private lands but state funded. (Photo by Joedson Alves/EPA/EFE)

The Spanish photographer Xavi Bou digitally combines sequential pictures of birds to create a single image, or chronophotograph, that reveals the shapes of their flight paths against Catalonian skies. His work shows the variety and beauty to be found in the daily activities of the local birds, including spiralling storks, swooping starlings and giddy swifts. Here: European herring gulls at Llobregat Delta. (Photo by Xavi Bou/Rex Features/Shutterstock)

Mr. Zhong Hua, of Johns Hopkins University School of Medicine, took this image of the peripheral nerves (those outside of the brain) in an 11.5-day-old mouse embryo, magnified five times. (Photo by Zhong Hua)

A performer dressed as Empress Huang of the China's Forbidden City takes part in a musical performance at a shopping mall in Kuala Lumpur on January 22, 2017 as part of the upcoming Lunar New Year celebrations marking the Year of the Rooster. (Photo by Manan Vatsyayana/AFP Photo)