An environmental activist adjusts his mask while taking part in “The Dead Sea Swim Challenge”, swimming from the Jordanian to Israeli shore, to draw attention to the ecological threats facing the Dead Sea, in Kibbutz Ein Gedi, Israel November 15, 2016. Swimmers from around the world plunged into the salty waters of the Dead Sea on Tuesday to attempt a seven-hour swim across the fabled lake in a bid to draw attention to its environmental degradation. Wearing protective masks and snorkels, 25 swimmers paddled through the muddy water to attempt the 9-mile (15-kilometer) swim from Jordan to Israel. (Photo by Nir Elias/Reuters)

Live octopus is a delicacy in South Korea but is a known choking hazard, since the still-moving suction cups can cause tentacle pieces to stick in a person's throat. A baby octopus is often consumed whole, while larger varieties are cut up and the still-wriggling tentacles eaten with a splash of sesame oil. Photo: A South Korean man and a woman eat a live octopus during an event to promote a local food festival in Seoul on September 12, 2013. (Photo by Jung Yeon-Je/AFP Photo)

Executive producer Dave Alpert attends the season five premiere of “The Walking Dead” at AMC Universal Citywalk on Thursday, October 2, 2014, in Universal City, Calif. (Photo by John Shearer/Invision for AMC/AP Images)

Three prostitutes lean out of a window in Santiago, Chile, in an attempt to entice customers inside, circa 1950. (Photo by Three Lions/Getty Images)

Damaged buildings stand in the rebel-controlled area of Maaret al-Numan in Idlib province, Syria September 6, 2016. (Photo by Ammar Abdullah/Reuters)

A Beija-Flor samba school member performs during the second night of the Carnival parade at the Sambadrome in Rio de Janeiro, Brazil on February 25, 2020. (Photo by Sergio Moraes/Reuters)

Star trails are pictured from a road in Singapore. These astonishing images of night sky are captured by Singapore based photographer Justin Ng. The pictures were taken between November 2013 to January 2014. It show's star trail caused by the earth's rotation and also can be achieved by zooming the DSLR lens inward or outward in small steps using a dedicated motorized zooming device. (Photo by Justin Ng/Barcroft Media)

Thomas Thwaites, a 34-year-old researcher from London, has spent the past year creating prosthetics that allow him to roam around on all fours like goat.