A woman looks at photographs of dogs to choose a pet to rent at Puppy The World on January 24, 2009 in Tokyo, Japan. Rent-a-dog is becoming increasingly popular amongst people who love dogs but are unable to look after a pet full time due to limited living space or long working hours. Customers pay the dog-rental outlet around 2500 yen (32.5 USD) for an hour, and usually take their rented pet for a walk along the nearby beach. (Photo by Junko Kimura/Getty Images)

A visitor to the New Museum walks through the “Carsten Holler: Experience”, exhibition at the museum on December 14, 2011 in New York City. The show, which has been called an art world amusement park, includes a 102-foot slide that corkscrews down from the fourth floor to the second; an installation of flashing lights that is supposed to make you hallucinate and a sensory-deprivation tank that is meant to resemble the Dead Sea. (Photo by Spencer Platt/Getty Images)

Eight-year-old handicapped Chinese girl Qian Hongyan crawls with two home-made props and part of a basketball at Zhuangxia Village on January 5, 2005 in Luliang County of Qujing City, Yunnan Province, China. The girl who lost both of her legs in a traffic accident in 2000 at the age of three, struggles to live her life with a basketball as an underprop, “walking” between school and home by herself. The girl's story is widely reported in the country, and experts from China Rehabilitation Research Center has come to Qian's home to help her for rehabilitative treatment early 2005. (Photo by China Photos/Getty Images)

Stefan Dobrovolny of Austria and Inigo Munoz Elorza of Spain (R) stand in front of a quad bike during a simulated Mars mission on Tyrolean glaciers in Kaunertal, Austria, August 7, 2015. The Austrian Space Forum is sending some of its researchers to practice weight-less walking in spacesuits on a glacier which resembles the terrain on Mars. (Photo by Dominic Ebenbichler/Reuters)

Pooh, a one-year-old cat, who lost his hind legs in an accident and has been given bionic paws, walks in a vet clinic in Sofia on January 31, 2017. Pooh, who is thought to have lost his legs in a car or train accident last April, is back on the prowl thanks to Bulgarian veterinary surgeon Vladislav Zlatinov. He is the first vet in Europe to successfully apply the pioneering method of Irish neuro-orthopaedic surgeon Noel Fitzpatrick, who shot to fame in 2009 when making Oscar the first bionic cat by fitting him with new hind legs in Britain. (Photo by Nikolay Doychinov/AFP Photo)

A man walks in the early morning to start his day picking tea leaves at a plantation in Nandi Hills, in Kenya's highlands region west of capital Nairobi, November 5, 2014. Emerald-coloured tea bushes blanketing the rolling hills of Nandi County have long provided a livelihood for small-scale farmers, helping make Kenya one of the world's biggest tea exporters. But ideal weather and bigger harvests, instead of producing bumper earnings, have led to a glut of Kenya's speciality black tea. (Photo by Noor Khamis/Reuters)

Canadian slackliner Mia Noblet walks on a slackline (25mm wide, 3mm thick and 60m long) during “Tianmen Mountain Female High-Heeled Highline Challenge” at Zhangjiajie National Forest Park on May 27, 2018 in Zhangjiajie, Hunan Province of China. 23-year-old Canadian slackliner Mia Noblet became the first one who finished the challenge in 22 minutes and 36 seconds while 32-year-old French slackliner Mini Guesdon broke the record in 9 minutes and 24 seconds during her second attempt on Sunday. (Photo by VCG/VCG via Getty Images)