Young U.S. visitors pose for a photograph next to a vintage car in Havana March 16, 2016. (Photo by Ueslei Marcelino/Reuters)

A boy sits on the back of a crocodile on May 19, 2018 at a pond in Bazoule in Burkina Faso, a village which happily shares its local pond with “sacred” crocodiles. Crocodiles may be one of the deadliest hunters in the animal kingdom, but in a small village in Burkina Faso it is not unusual to see someone sitting atop one of the fearsome reptiles. According to local legend, the startling relationship with the predators dates back to at least the 15 th century. The village was in the grip of an agonising drought until the crocodiles led women to a hidden pond where the population could slake their thirst. (Photo by Olympia de Maismont/AFP Photo)

Aldi SugandaRizal (2 years-old) smoking a cigarette while playing at the family home in Sekayu district, South Sumatera, Indonesia on May 23, 2010. (Photo by Ardiles Rante/Barcroft Media)

Soldiers of People's Liberation Army (PLA) Lanzhou Military Region jump through a burning obstacle during a training session at a military base in Tianshui, Gansu province, China, January 6, 2016. (Photo by Reuters/Stringer)

US freestyler, gold medalist Mcrae Williams competes during the men' s SlopeStyle (SS) finals at the FIS Snowboard and Freestyle Ski World Championships 2017 in Sierra Nevada on March 19, 2017. (Photo by Albert Gea/Reuters)

Model Joanna Krupa poses during a protest against animals in circuses, in front of the Houses of Parliament in London, Britain, September 11, 2017. (Photo by Hannah McKay/Reuters)

A photo taken on August 29, 2014, shows Mount Tavurvur erupting in eastern Papua New Guinea, spewing rocks and ash into the air, forcing the evacuation of local communities and international flights to be re-routed. Mount Tavurvur, which destroyed the town of Rabaul when it erupted simultaneously with nearby Mount Vulcan in 1994, rumbled to life early in the morning on the tip of the remote island of New Britain. (Photo by Oliver Bluett/AFP Photo)

Participants in traditional dress ride on horseback as they enjoy the atmosphere at the Feria de Abril (April's Fair) on April 12, 2016 in Seville, Spain. The Feria de Abril has a history that dates back to 1857 and takes place a fortnight after Easter each year. The origin of the fair was a cattle market but the event quickly turned its goal from commerce to having fun. More than 1 million local and international participants are expected to attend the Feria de Abril. (Photo by David Ramos/Getty Images)