Akram Abu al-Foz places a painted empty shell on top of a Christmas tree he decorated from empty shells he collected in the rebel held besieged city of Douma, in the eastern Damascus suburb of Ghouta, Syria December 23, 2016. (Photo by Bassam Khabieh/Reuters)

Two attendees compete in the biggest vape cloud competition at the Vape Summit 3 in Las Vegas, Nevada May 2, 2015. According to new research provided to Reuters, youngsters say that performing tricks is one of the top two reasons they began using e-cigs. (Photo by David Becker/Reuters)

A Muslim pilgrim makes his way to Hera cave, where Muslims believe Prophet Mohammad received the first words of the Koran through Gabriel, at the top of Mount Al-Noor during the annual haj pilgrimage in the holy city of Mecca, September 21, 2015. (Photo by Ahmad Masood/Reuters)

Yenny Mamani "Marta la Altena", top, grabs Leonor Cordova "Angela la Simpatica" in a hold during a Bolivian wrestling Cholitas fight in Madrid, Spain, Thursday October 8, 2015. (Photo by Paul White/AP Photo)

Hikers walk to reach the top of Naqba Rum area in South Sinai, Egypt, November 20, 2015. Bedouins in the "Sinai is Safe" group guided more than 100 hikers over a 25 km (15 mile) trek over the trails of the White Canyon and the Closed Canyon. The NGO aims to challenge mainstream perceptions of the area by encouraging Nile Valley residents to explore the untamed wilderness with the Bedouin tribes. (Photo by Asmaa Waguih/Reuters)

A handout picture provided by Global newsroom of Czech Martin Sonka (C) leading Nigel Lamb (top) of Great Britain and Yoshihide Muroya of Japan (down) along the Mount Fuji prior the third stage of the Red Bull Air Race World Championship in Chiba, Japan on June 1, 2016. (Photo by Predrag Vockovic/EPA/Global Newsroom)

Migrants ride on top of a northern bound train toward the US-Mexico border in Juchitan, southern Mexico, Monday, April 29, 2013. Migrants crossing Mexico to get to the U.S. have increasingly become targets of criminal gangs who kidnap them to obtain ransom money. (Photo by Eduardo Verdugo/AP Photo)

Four-man bicycle is powered by five chains and has brakes on both its wheels, 1948. The bike was built by Art Rothschild (top position) who broke three ribs while learning how to ride it. (Photo by Wallace Kirkland/Time & Life Pictures)