A photograph released to Reuters on August 22, 2014 shows the remains of an ancient Mayan city in Lagunita May 30, 2014. Archaeologists have found two ancient Mayan cities hidden in the jungle of southeastern Mexico, and lead researcher Ivan Sprajc, an associate professor at the Research Center of the Slovenian Academy of Sciences and Arts, says he believes there are “dozens” more to be found in the region. (Photo by Reuters/Research Center of the Slovenian Academy of Sciences and Arts)

Ukraine's Leonid Stadnyk, who stands at a height of 2.53 metres (eight feet four inches) and may be considered the world's tallest living man, near his house in the village of Podolyantsi in Ukraine's Zhytomyr region, about 200 km (124 miles) from the capital Kiev, 2005. (Photo by Reuters/Stringer)

In this Thursday, May 8, 2014 photo, Iranian coal miners push metal carts to be loaded with coal at a mine near the city of Zirab 212 kilometers (132 miles) northeast of the capital Tehran, on a mountain in Mazandaran province, Iran. International sanctions linked to the decade-long dispute over Iran's nuclear program have hindered the import of heavy machinery and modern technology in all sectors, and coal mining is no exception. (Photo by Ebrahim Noroozi/AP Photo)

A young performer cries as she parades during the Bun Festival on Cheung Chau island in Hong Kong Tuesday, May 6, 2014. Bun Festival, the Taoist God of the Sea, is worshipped and evil spirits are believed to be scared away by loud gongs and drums during the procession. The celebration includes bun scrambling, parades, opera performances, and children dressed in colorful costumes. (Photo by Kin Cheung/AP Photo)

Yasothon resident look on as huge, handmade rockets are launched into the air during the Bun Bang Fai festival on May 11, 2014 in Yasothon, Thailand. During the Bun Bang Fai rocket festival, Thai residents launch enormous home-made rockets into the air to gain Buddhist merit and to celebrate the beginning of the rainy season. (Photo by Taylor Weidman/Getty Images)

A man stands at a passenger train damaged in a collision with a freight train in Moscow region May 20, 2014. The passenger train on its way to Moldova collided with a freight train near Moscow on Tuesday, killing at least four people and injuring 15, a spokeswoman for Russia's Emergencies Ministry said. The reason for the collision, near the town of Naro-Fominsk 55 km (34 miles) southwest of Moscow, was not immediately clear. (Photo by Grigory Dukor/Reuters)

Employees conduct a final check to fix any cavities in the seams of balls inside the soccer ball factory that produces official match balls for the 2014 World Cup in Brazil, in Sialkot, Punjab province May 16, 2014. It was when he felt the roar of the crowd at the 2006 World Cup in Germany that Pakistani factory owner Khawaja Akhtar first dreamt up a goal of his own: to manufacture the ball for the biggest soccer tournament on the planet. Last year he finally got his chance – but only 33 days to make it happen. (Photo by Sara Farid/Reuters)

Elaborately dressed monks costumed as wrathful guardian spirits perform ceremonial dances during the Tenchi Festival on May 25, 2014 in Lo Manthang, Nepal. The Tenchi Festival takes place annually in Lo Manthang, the capital of Upper Mustang and the former Tibetan Kingdom of Lo. Each spring, monks perform ceremonies, rites, and dances during the Tenchi Festival to dispel evils and demons from the former kingdom. (Photo by Taylor Weidman/Getty Images)