The giant inflatable Rubber Duck installation by Dutch artist Florentijn Hofman floats on the Parramatta River, as part of the 2014 Sydney Festival, in Western Sydney, January 10, 2014. The creation is five stories tall and five stories wide and has been seen floating in various cities around the world since 2007. (Photo by Jason Reed/Reuters)

An Amur tiger walks across a passageway after a news conference at the Philadelphia Zoo, Wednesday, May 7, 2014, in Philadelphia. The see-through mesh pathway called Big Cat Crossing is part of a national trend called animal rotation that zoos use to enrich the experience of both creatures and guests. (Photo by Matt Slocum/AP Photo)

A view of the spectacular colour of clouds at sunset on January 17, 2005 in Beijing, China. (Photo by China Photos/Getty Images)

Philadelphia Phillies Ben Francisco reacts after being hit in the head with a pitch by Cincinnati Reds Logan Ondrusek during the MLB National League Division Series baseball playoffs in Philadelphia, Pennsylvania, United States in this October 8, 2010 file photo. (Photo by Tim Shaffer/Reuters)

Alice Cooke at the Sydney Women’s Reformatory in 1922. By the time she was 24 Alice Cooke had created an impressive number of aliases and at least two husbands, and was convicted of bigamy and theft. (Photo by My Colorful Past/Mediadrumworld)

Clouds gather as walkers pause atop a ridge in Mountain View, California January 7, 2016. (Photo by Noah Berger/Reuters)

An ethnic Armenian fighter carries Kalashnikov machine guns to his comrade-in-arms at Martakert province in the separatist region of Nagorno-Karabakh, Azerbaijan, Monday, April 4, 2016. (Photo by Vahan Stepanyan/PAN Photo via AP Photo)

A participant covered in coloured powder gestures as she stands near a Syrian army soldier during “I Love Damascus” marathon at Umayyad Square in Damascus, Syria October 7, 2016. (Photo by Omar Sanadiki/Reuters)