Competitors line up their boats for some formalities during the Aberdeen Dragon Boat Races. (Photo by Jessica Hromas)

In this photo provided by Skydive Chicago, escape artist Anthony Martin falls while handcuffed and locked inside a box after being dropped from an airplane over Ottawa, Ill., Tuesday, August 6, 2013. (Photo by Joe Silva/AP Photo/Courtesy of Skydive Chicago)

A window cleaner passes a lighter to his colleague while rappelling from a new building in Tianjin March 23, 2007. (Photo by Reuters/Stringer)

Handout photo issued by Easyart of an experimental motorcycle as an archive of weird and wacky innovations has been unearthed by an amateur historian as he trawled through a collection of images spanning the last 100 years. (Photo by Easyart/PA Wire)

Children guarded by Hungarian police play on the ground after being detained along with other migrants who illegally crossed from Serbia to Hungary near the village of Asotthalom, Hungary, September 16, 2015. (Photo by Dado Ruvic/Reuters)

Hot air balloons fly during the Irish hot air ballooning championships in Galway, Ireland September 26, 2016. (Photo by Clodagh Kilcoyne/Reuters)

During the spring harvest season, a group of traditional Malaysian honey hunters travel to the rainforest near the Thai border to collect honeycombs from giant bees – and risk their lives climbing 200ft trees. Here: Bees are sensitive to light, which makes them follow the glowing embers down to the ground. (Photo by Hasnoor Hussain/The Guardian)

Kaw-Claa, a Tlingit native woman in full potlatch dancing costume, 1906. (Photo by Case & Draper/Buyenlarge/Getty Images)