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)

Israeli fashion design student from the Shenkar College of Engineering and Design Danit Peleg (R) assists a fashion blogger to wear an outfit from her graduate collection during a conference on 3-D printing in Tel Aviv, Israel September 3, 2015. Peleg, 27, says she spent over 2000 hours to create her graduate collection which is made solely from home 3-D printers. International fashion bloggers, taking part in a project supported by “Stand With Us Israel fellowship”, a non-profit organisation, attended the conference and tried on Peleg's clothing before listening to her talk about her collection. (Photo by Nir Elias/Reuters)

A traffic police woman whistles at a pedestrian, Monday, July 27, 2015, in Pyongyang, North Korea where its citizens are having a one-day national holiday to celebrate the country's 62nd anniversary of the armistice that ended the Korean War. (Photo by Wong Maye-E/AP Photo)

The British Breitling Wingwalkers, Danielle Hughes and Emily Guilding, soar above the Palm Jumeirah in Dubai at 1,500 feet (460 meters) in excess of 100mp/h, ahead of their Dubai debut performance at the 2014 UIM Skydive Dubai XCAT World Powerboating Series, on Saturday, 13th December 2014. The British team is the only aerobatic formation display team who employ full time wingwalkers and fly their two Breitling-liveried 1930's Boeing Stearman bi-planes at Air Shows and major sporting events around the world. (Photo by Katsuhiko Tokunaga/Breitling via AP Images)

An injured fan is helped by a riot policeman during clashes between Red Star Belgrade and Partizan Belgrade fans in the stadium before the teams' Serbian Superliga soccer match in Belgrade, April 25, 2015. Serbian league leaders Partizan Belgrade held champions and bitter city foes Red Star to a 0-0 draw in a derby match marred by bad crowd trouble before kickoff on Saturday. The start was delayed for 45 minutes after home Red Star supporters pelted riot police with seats and flares, forcing officers to retreat from the north tier that houses the club's diehard fans. (Photo by Marko Djurica/Reuters)

Attendees look at Volkswagen's BUDD-e, a long distance electric vehicle, displayed during a press event at CES 2016 at The Chelsea at The Cosmopolitan of Las Vegas on January 5, 2016 in Las Vegas, Nevada. CES, the world's largest annual consumer technology trade show, runs from January 6-9 and is expected to feature 3,600 exhibitors showing off their latest products and services to more than 150,000 attendees. (Photo by David Becker/Getty Images)

PALEMBANG, SUMATRA, INDONESIA - NOVEMBER 14: Fitriyani Fitriyani (L) of Indonesia and Janice Ng (R) of Singapore compete in the Sport Climbing Womens Speed Track Finals on day four of the 2011 Southeast Asian Games at Jakabaring Sports Complex on November 14, 2011 in Palembang, Sumatra, Indonesia. (Photo by Matt King/Getty Images)