Protesters wearing masks perform during anti-austerity and anti-graft protests in Ljubljana, Slovenia, on January 11, 2013. More than 5,000 Slovenians gathered in the center of Ljubljana on Friday to protest against a corruption scandal that threatens to bring down the government. Slovenia's anti-corruption commission said earlier this week that Prime Minister Janez Jansa had been unable to explain the source of some of his income in recent years. (Photo by Srdjan Zivulovic/Reuters via The Atlantic)

Rubber masks depicting U.S. President-elect Donald Trump are seen at the Ogawa Studios, a mask making company, in Saitama, Japan, November 21, 2016. (Photo by Toru Hanai/Reuters)

A masked reveller poses during the Venice Carnival in Venice, Italy February 12, 2017. (Photo by Tony Gentile/Reuters)

Ucil, a trained monkey, takes part in a street performance on June 1, 2011 in Jakarta, Indonesia. The street performances usually involve the monkeys wearing masks, such as dolls' heads or attire to mimic humans, with the monkeys trained to act out human activities such as shopping, riding bicycles or other simulations of human behaviour. Poverty drives the handlers to exploit the monkeys in the hope of earning small change, but the effect and cruelty to the monkeys is a cause that charities such as the Jakarta Animal Aid Network are increasingly taking up. (Photo by Ulet Ifansasti/Getty Images)

A seven-week-old Persian kitten peers into a goldfish bowl, 9th October 1972. (Photo by William Vanderson/Fox Photos/Hulton Archive/Getty Images)