A fox pounces on a mouse in the snowy hills on the border of the Czech Republic and Slovakia. (Photo by Johnny Krüger/Mediadrumimages)

American free climber Dean Potter walks on a 41-meter-long and two-centimeter-wide slackline over Enshi Grand Canyon at an altitude of 1,800m on April 22, 2012 in Enshi, Hubei Province of China. Potter successfully finished the lone slackline walk in about three minutes without taking any protective measures. (Photo by ChinaFotoPress/ChinaFotoPress)

Pakistani youths cool off in a stream during hot weather on the outskirts of Islamabad on April 29, 2016. Pakistan's Meteorological Department has forecast hot and dry weather in most parts of the country with the highest temperatures recorded at 41 celsius in the southern Sindh province. (Photo by Aamir Qureshi/AFP Photo)

South Korean prostitutes hide their identities as they participate in a rally on September 22, 2005 in Seoul, South Korea. Prostitutes rallied against government law aimed at the s*x industry. (Photo by Chung Sung-Jun/Getty Images)

A model poses at the Le Silla Spring/Summer 2012 presentation as part Milan Womenswear Fashion Week on September 23, 2011 in Milan, Italy. (Photo by Vincenzo Lombardo/Getty Images for Le Silla)

Singer Taylor Swift poses at the 2016 iHeartRadio Music Awards in Inglewood, California, April 3, 2016. (Photo by Danny Moloshok/Reuters)

Rugby Union, Hong Kong Sevens, Hong Kong Stadium on April 9, 2016: A fan wearing a mask is hugged. (Photo by Bobby Yip/Reuters)

A woman gets a pedicure in Port-au-Prince, Haiti, on October 13, 2017. (Photo by Andres Martinez Casares/AP Photo)