Participants gather in the Union Square subway station during the annual No Pants Subway Ride on January 8, 2012 in New York City. The annual event is staged by the group Improv Everywhere which encourages people in dozens of cities worldwide to discard their pants while riding the subway. (Photo by Mario Tama/Getty Images)

Commuters walk up the redesigned subway stairs at the Tanjong Pagar subway station on August 23, 2011 in Singapore. The subway stairs have been repainted in bright colours and slogans encouraging people to take the stairs, by way of promoting fitness in the city. (Photo by Chris McGrath/Getty Images)

Paramedics carry an injured woman out from a subway station after a rush-hour subway train derailment, to be transported by a medical helicopter in Moscow, Russia, on Tuesday, July 15, 2014. A rush-hour subway train derailed in Moscow Tuesday, killing 20 people and injuring at least 150, emergency officials said. Several cars left the track in the tunnel after a power surge triggered an alarm, which caused the train to stop abruptly. (Photo by Ivan Sekretarev/AP Photo)

Daisuke Nagasawa, 49, has spent the past few years taking his two faithful cats, Daikichi and Fuku-Chan, around the world with him. Here: Daisuke Nagasawa travels nationally and internationally with his beautiful kitties Fuku-Chan and Daikichi. The two pose under the iconic Japanese cherry blossoms. (Photo by Daisuke Nagasawa/Caters News Agency)

If Kim Kardashian was a feline shed be purr-fect for this new book which features a collection the worlds best cat “selfies”. The furry frames have been compiled by cat owner Charlie Ellis who has scoured the globe for the perfect puss pictures. In his book “Cat Selfies” moggies try their hand at the craze most of their humans have become addicted to posting on social media. And it turns out cats might be better at taking photos than their owners with a variety of poses captioned in the book. (Photo by Charlie Ellis/Caters News)

This photo provided by Running Press and Quarto, Inc. shows Feline Fox from the book, “Cats in Hats”, published by Running Press. The book released on March 24, 2015. (Photo by Liz Coleman/Running Press/Quarto, Inc. via AP Photo)

These adorable cats – which are twins – showcase their contrasting blue and green eyes. The cats have a condition called heterochromia iridis, which causes each eye to vary in color. (Photo by @sis.twins/Caters News Agency)