People walk through crop circles in a cornfield near Raisting, Germany, on July 28, 2014. According to media reports, a balloonist had discovered the circle some days ago. Since then, hundreds of people came to the field to watch it, however it is unclear who did create the pattern. (Photo by Karl-Josef Hildenbrand/DPA)

Robot couple Xiaolan (L) and Xiaotao carry trays of food at a restaurant in Jinhua, Zhejiang province, China, May 18, 2015. The restaurant, which opened on Monday, has two robots delivering food for customers. The robots were designed as a couple, Xiaolan and Xiaotao, according to local media. (Photo by Reuters/Stringer)

The Facebook website is displayed on a laptop computer on May 9, 2011 in San Anselmo, California. An investigation by The Pew Research Center found that Facebook has become a player in the news industry as the popular social media site is driving an increasing amount of traffic to news web sites. (Photo Illustration by Justin Sullivan/Getty Images)

A police officer jump ropes with a police dog at a police dog training base on July 11, 2011 in Beijing, China. The Police Dog Training Base was opened to a media visit to show the dogs skills to the public. (Photo by ChinaFotoPress/Getty Images)

Egyptian President Hosni Mubarak speaks to the media after talks with German Chancellor Angela Merkel at the Chancellery on April 23, 2008 in Berlin, Germany. (Photo by Sean Gallup/Getty Images)

Spanish artist Romulo Celdran (b. 1973) brings exquisite technical skill, a fastidious eye, and a scientific attention to detail to both his mixed-media drawings on board and his larger-than-life sculptures of quotidian objects.

Nekama, a baby North Chinese leopard, emerges from a basket at her official presentation to the media at Tierpark zoo on March 15, 2011 in Berlin, Germany. Nekama was born on January 7, 2011 and currently weighs 4.5 kg.

A member of the Fuerza Civil (Civil Force) police unit takes part in a simulated crime situation during a media presentation to show the police model that the federal government wants for the rest of the country, at the police academy in Monterrey December 17, 2014. Fuerza Civil, a tactical team of the police unit trained by the army, was created by the Nuevo Leon government in 2011 to curb down corruption and infiltration by drug gangs in the police corps, local media reported. Promising a new law to stop the infiltration of local governments by organized crime, President Enrique Pena Nieto pledged to reform the penal system and send an proposal to Congress to unify multi-layered police forces in Mexico's 31 states. (Photo by Daniel Becerril/Reuters)