Two people wearing animal costumes join others as people gather to celebrate the Winter Solstice at Stonehenge in England Tuesday December 22, 2015. The winter solstice is celebrated by many people around the world as the beginning of the return of the sun. (Photo by Ben Birchall/PA Wire via AP Photo)

An explosion at a petrochemical plant is seen in Rizhao, Shandong province, July 16, 2015. According to Xinhua News Agency, a fire broke out after the explosion, which was caused by a liquified hydrocarbon leak at the plant, on Thursday morning. There was no report of casualties yet. (Photo by Reuters/China Daily)

A member of the “Exit Point” amateur rope-jumping group jumps from a 44-metre high (144-feet high) waterpipe bridge in the Siberian Taiga area outside Krasnoyarsk, September 28, 2014. Fans of rope-jumping, a kind of extreme sport involving a jump from a high point using an advanced system of amortization including mountaineering and rope safety equipment, attended the Golden Autumn group's jumping season. (Photo by Ilya Naymushin/Reuters)

Syrian refugees sit behind barbed wire as they wait to cross into Macedonia at the Greek-Macedonian border, near the village of Idomeni, August 21, 2015. (Photo by Yannis Behrakis/Reuters)

A demonstrator throw a firebomb during clashes with Turkish riot police officers in Istanbul, Turkey, Friday, May 1, 2015. The government assigned 30,000 police officers backed by helicopters as workers and demonstrators determined to defy a government ban, tried to march to iconic Taksim Square, where 35 people were killed during May Day celebration in 1977. (Photo by Emrah Gurel/AP Photo)

Children react as a carnivorous theropod known as the Australovenator dinosaur walks through crowds along the Southbank, in London, Monday, February 18, 2013. The dinosaur is one of many that can be visited at the Erth's Dinosaur Petting Zoo, visiting from Australia, the creatures can be touched and fed at the Southbank Centre. (Photo by Kirsty Wigglesworth/AP Photo)

Reuters photographer Siegfried Modola gained access to a circumcision ceremony in rural Kenya for young girls of the Pokot tribe, in Baringo County. Here: a Pokot girl, covered in animal skins, walks to a place where she will rest after being circumcised in a tribal ritual in a village about 80 kilometres from the town of Marigat in Baringo County, October 16, 2014. (Photo by Siegfried Modola/Reuters)

Robert The Bruce's army from The Clanranald Trust during a rehearsal for the Battle of Bannockburn re-enactment performance which will be staged at the Bannockburn Live Event in Bannockburn, the 700th anniversary of the battle, on June 27, 2014. (Photo by Andrew Milligan/PA Wire)