Two three-month-old female white Bengal tiger cubs play with a zoo keeper in their enclosure at the Buenos Aires' Zoo, in Argentina, on April 17, 2014. Captive white Bengal tiger Cloe, gave birth to three cubs – two females and one male – on January 14, 2014. (Photo by Juan Mabromata/AFP Photo)

A “Maya” girl sits in an altar during the traditional celebration of “Las Mayas” on the streets in Colmenar Viejo, near Madrid, Spain, Friday, May 2, 2014. The festivity of the Maya comes from pagan rites and dates from the medieval age, appearing in ancient documents, it takes place every year in the beginning of May and celebrates the beginning off the spring. A girl between 7 and 11years is chosen as “Maya” and should sit still, serious, and quiet for a couple of hours in an altar on the street decorated with flowers and plants, afterwards they walk to the church with their family where they attend a ceremony. (Photo by Daniel Ochoa de Olza/AP Photo)

The Pied Piper of Hamelin, actually city tourism employee Michael Boyer, leads local children dressed as rats through a quiet street on November 19, 2012 in Hameln, Germany. The Pied Piper (in German: Der Rattenfaenger), is one of the many stories featured in the collection of fairy tales collected by the Grimm brothers, and the 200th anniversary of the first publication of the stories will take place this coming December 20th. Boyer, a U.S. citizen who has lived in Hameln for 15 years, and city children regularly perform a reenactment of the Pied Piper tale throughout the summer months. The Grimm brothers collected their stories from oral traditions in the region between Frankfurt and Bremen in the early 19th century, and the works include such global classics as Sleeping Beauty, Little Red Riding Hood, Rapunzel, Cinderella and Hansel and Gretel. (Photo by Sean Gallup)

Emma Watson attends the Elle Style Awards 2014 at one Embankment on February 18, 2014 in London, England. (Photo by Tim P. Whitby/Getty Images)

Cat lounges and makes itself at home at the new Cat Café by Purina ONE on Wednesday, April 23, 2014 in New York. (Photo by Amy Sussman/Invision for Purina ONE/AP Images)

The Invasion. A quiet street in Macau. Modernization around is quickly changing the city, as documented by Paul Tsui. (Photo by Paul Tsui/National Geographic Travel Photographer of the Year Contest)

A one and a half months old baby elephant stands close to its mother at Chitwan National Park in Chitwan, south of Kathmandu December 30, 2014. (Photo by Navesh Chitrakar/Reuters)

The image of President George Washington is seen on an engraving plate for a one dollar bill at the Bureau of Engraving and Printing in Washington November 14, 2014. (Photo by Gary Cameron/Reuters)