These two young siblings appear to cling on to a tree for dear life and even hold hands as they learn the ropes of climbing, on June 25, 2013. (Photo by Tim Fitzharris/Minden/Solent)

A jockey drives a buffalo in the annual water buffalo race, part of a week-long festival in homage to the animals and in celebration of the rice harvest in Chonburi, Thailand on April 1, 2016. (Photo by Vichaya Pop/Barcroft Media)

A woman takes a picture of a Maserati's SUV model Levante during the Auto China 2016 show in Beijing, China April 25, 2016. (Photo by Kim Kyung-Hoon/Reuters)

Two Bulgarian tourists pose in front of the Eiffel Tower in Paris on their last day in the capital on March 24, 2014. (Photo by Franck Fife/AFP Photo)

A soldier poses with a Hythe Mk III Gun Camera during training activities at Ellington Field, Houston, Texas in April of 1918. The Mk III, built to match the size, handling, and weight of a Lewis Gun, was used to train aerial gunners, recording a photograph when the trigger was pulled, for later review, when an instructor could coach trainees on better aiming strategies. (Photo by Harry Kidd/WWI Army Signal Corps Photograph Collection via The Atlantic)

Thailand's King Bhumibol Adulyadej in serious portrait January 01, 1960. Thailand's Royal Palace said on Thursday, October 13, 2016, that Thailand's King Bhumibol Adulyadej, the world's longest-reigning monarch, has died at age 88. (Photo by John Dominis/The LIFE Picture Collection/Getty Images)

Tennis star Maria Sharapova poses with a Porsche 911 RSR race car at the 2016 Los Angeles Auto Show in Los Angeles, California, U.S November 16, 2016. (Photo by Mike Blake/Reuters)

An anti-Gaddafi fighter tests an anti-aircraft gun southwest of Sirte, Libya one of Muammar Gaddafi's last remaining strongholds, September 16, 2011. A timeline of images dating from 2010 from Sirte, Libya, the home town of deposed Libyan leader Muammar Gaddafi. Libyan forces battling Islamic State in the city of Sirte say they have defeated the militant group after months of street to street fighting backed by U.S. air strikes. Islamic State took control of the city more than a year ago and set up its main base outside Syria and Iraq. (Photo by Goran Tomasevic/Reuters)