A combination picture shows participants in costume at a Halloween parade in Kawasaki, south of Tokyo, October 25, 2015. More than 100,000 spectators turned up to watch the parade, where 2,500 participants dressed up in costumes, according to the organiser. (Photo by Yuya Shino/Reuters)

Suspension artist and LUSH Cosmetics employee Alice Newstead inspects shark hooks that she had pierced into her skin during a demonstration against the shark fin trade at a LUSH Cosmetic store on August 24, 2011 in San Francisco, California.

A rat being trained by the Cambodian Mine Action Centre (CMAC) is pictured on an inactive landmine field in Siem Reap province July 9, 2015. Gambian pouched rats were deployed to Cambodia from Tanzania in April by a Belgian non-profit organization, APOPO, to help clear mines. They've been trained since they were 4 weeks old. Cambodia is still littered with landmines after emerging from decades of civil war, including the 1970s Khmer Rough “Killing Fields” genocide, leaving it with one of the world's highest disability rates. APOPO has used the rodents for mine-clearing projects in several countries, including Angola, Mozambique, Thailand, Laos, and Vietnam. (Photo by Samrang Pring/Reuters)

A soup for the students is pictured during an activity for the end of the school year at the Padre Jose Maria Velaz school in Caracas, Venezuela July 12, 2016. Due to the faltering socialist economy and the plunge in global oil prices, Venezuela has been in recession since early 2014. Due to the faltering socialist economy and the plunge in global oil prices, Venezuela has been in recession since early 2014. It suffers from the world's highest inflation and is experiencing shortages of basic goods, from milk to medicines. (Photo by Carlos Jasso/Reuters)

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.

The fourth annual BigPicture Natural World Photography Competition aims to celebrate the diversity of life on Earth, and encourages people to protect and conserve it. Here: “The Salmon Catchers”. Terrestrial Wildlife. To capture this view of a mother grizzly bear and her cub, photographer Peter Mather set up a camera trap on a log that he knew the bears tended to traverse while fishing for salmon, in the Yukon River watershed in Canada. (Photo by Peter Mather/BigPicture Natural World Photography Competition 2017)

An old woman looks from inside a car with bullet holes and shattered windows as she flees fighting in the eastern Ukrainian town of Slaviansk June 9, 2014. REUTERS/Gleb Garanich.

Bob Steele, of Jefferson, Texas, positions his bears during The Great Bear Show at the Dubuque (Iowa) County Fair on July 25, 2012. (Photo by Jessica Reilly/Telegraph Herald)