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)

Russia's Maria Stavitskaia performs during the ladies short program at the Rostelecom Cup ISU Grand Prix of Figure Skating in Moscow November 14, 2014. (Photo by Grigory Dukor/Reuters)

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)

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)

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)

A young man “painting” the Eiffel Tower. (Photo by Keystone/Getty Images). 9th May 1970