Riot police stood by the gates of parliament in Nairobi, Kenya, Tuesday, May 14, 2013, during a demonstration against members of parliament who demanded higher wages. Demonstrators released two dozen piglets and poured blood on the pavement to protest the demands for a wage hike. (Photo by Carl de Souza/AFP Photo)

Devotees attend the annual voodoo festival in Ouidah January 10, 2016. The national voodoo holiday in the West African country of Benin had a distinctively political accent this year as practitioners from Africa and the Americas gathered on Sunday to offer prayers and sacrifices for peace. Hundreds of followers of the traditional religion gathered in the Atlantic coast town of Ouidah, once an important port in the slave trade, to pray for calm during the tiny country's presidential election scheduled for February. (Photo by Akintunde Akinleye/Reuters)

Skiers and snow boarders descend from a slope as they attempt to break the record for mass skiing in swimming suits at Rosa Khutor resort near Sochi, Russia, April 9, 2016. (Photo by Kazbek Basayev/Reuters)

A girl dressed up as a emissary of the Three Wise Men poses for a photo as she waits for their arrival in a helicopter to take part in the traditional Epiphany parade in Ronda, Spain, January 5, 2018. (Photo by Jon Nazca/Reuters)

Rock and roll musician Elvis Presley during a press conference after his first performance at the International Hotel in Las vegas, Nevada on August 1, 1969. (Photo by Michael Ochs Archives/Getty Images)

A cosplayer uses moving stairs during the first public day of the world's largest computer games fair Gamescom in Cologne, Germany August 23, 2017. (Photo by Wolfgang Rattay/Reuters)

Competitors warm up backstage during the Arnold Classic Europe bodybuilding event in Madrid, Spain, September 25, 2015. (Photo by Susana Vera/Reuters)

Bonbibi, Treehouse Point, Fall City, WA. The Bonbibi is balanced on two steel yokes. The yokes spread out the load and allow for tree growth and movement in the wind. A small deck hangs from the beams below and uses the treehouse itself to shelter guests. (Photo by Pete Nelson)