Afghan children have ice cream during the Afghan New Year (Newroz) celebration in Kabul March 21, 2014. Afghanistan uses the Persian calendar which runs from the vernal equinox. The calendar takes as its start date the time when the Prophet Mohammad moved from Mecca to Medina in 621 AD. The current Persian year is 1393. (Photo by Ahmad Masood/Reuters)

A stunt rider jumps over spectators after the final stage of the annual ABSA Cape Epic mountain bike stage race, Cape Town, South Africa, 30 March 2014. The multi day stage race is know as the “Tour de France” of mountain biking and sees 1,200 riders riding 720km in seven days. The race includes the worlds leading professional racers along with amateur cyclists. (Photo by Kim Ludbrook/EPA)

Curator Anna Reynolds with a doll called Pamela and a toy horse on wheels at the launch of the summer exhibition Royal Childhood at Buckingham Palace, London, which celebrates royal childhood with toys and family gifts belonging to the royal children when they were growing up, on April 2, 2014. (Photo by Sean Dempsey/PA Wire)

Residents observe a police officer take up position during an operation at the Mare slums complex in Rio de Janeiro March 25, 2014. The federal troops have taken control of security operations in Mare slums complex to help quell a surge in violent crime following attacks by drug traffickers on police posts in three slums on the north side of the city, government officials said. (Photo by Ricardo Moraes/Reuters)

Polar bear twins make their first public appearance with their mother “Freedom” at Ouwehands Zoo Rhenen, in Rhenen, The Netherlands, 19 February 2015. The twins, who were born in November 2014, have not been named because their gender has not yet been determined. (Photo by Bart Maat/EPA)

A surfer drops in on a large wave at Praia do Norte, in Nazare December 11, 2014. Praia do Norte beach has gained popularity with big wave surfers since Hawaiian surfer Garrett McNamara broke a world record for the largest wave surfed here in 2011. (Photo by Rafael Marchante/Reuters)

A woman rolls a marijuana cigarette during the first “Expo Cannabis” fair in Montevideo December 14, 2014. Expo Cannabis offers conferences about different topics such as the medicinal use of cannabis and cultivation techniques as well as displaying hemp goods, cannabis cultivation items and seeds. (Photo by Andres Stapff/Reuters)