Brett Throckmorten of Barnes Bullets shows Logan Wingo how to sight down an electronic rifle in the trade booth area during the National Rifle Association's annual meeting in Nashville, Tennessee, April 11, 2015. (Photo by Harrison McClary/Reuters)

Animal rights activists covered with fake blood sit on the floor during a protest against the use of animals in research to mark World Day for Animals in Laboratories in central Madrid April 24, 2014. The sign reads, “How many rabbits do your shampoo kill?”. (Photo by Andrea Comas/Reuters)

Camera trapper Xavier Hubert-Brierre put this large mirror on the side of a road through the jungle in Gabon and left a camera there to record how the animals would respond to their own reflections. A silverback gorilla thought it was seeing another silverback and responded by trying to scare off the potential challenger… (Photo by Xavier Hubert-Brierre/Johns Hopkins University Press)

Tibetan pilgrims walk outside the Sera Monastery in Lhasa, Tibet Autonomous Region, China, 11 September 2016. Sera Monastery is known as one of the “great three” Gelug university monasteries of Tibet founded in 1419. (Photo by How Hwee Young/EPA)

A woman instructs a boy on how to pose for pictures in front of a mural depicting Soviet pilot Valery Chkalov – who took a non-stop flight over the Arctic and landed in the US state of Washington in 1937 – at Chkalovskaya metro station in Moscow on August 14, 2019. (Photo by Yuri Kadobnov/AFP Photo)

Models show creations by Chinese graduates from the China Academy of Art School of Design during the Show Town China Graduate Fashion Week in Beijing, China, 13 May 2018. (Photo by How Hwee Young/EPA/EFE)

Dead leaf or almost by Guilhem Duvot. Taken in Nován Stráž, Slovakia. Describe what is pictured? A dead leaf grasshopper. How does this image fit with the theme of the competition? The perfect camouflage – nature is amazing. I saw the grasshopper only because it jumped. (Photo by Guilhem Duvot/Royal Society of Biology)

Elvis Presley tribute artist Bruce Stewart (L) of Georgian Bay, Ontario passes Lorenz Francke of Scarborough, Ontario during the four-day Collingwood Elvis Festival in Collingwood, Ontario July 25, 2015. Featuring over 120 Elvis tribute artists, it is the world's largest Elvis festival and last year hosted 30,000 visitors. (Photo by Chris Helgren/Reuters)