A dog in a purple dress, taken in El Dorado, Arkansas, December 2016. The dapper dogs in clothes are back with a second series, and they’re feeling festive. (Photo by Tammy Swarek/Barcroft Images)

A Kevo smart lock is demonstrated during the 2015 International Consumer Electronics Show (CES) in Las Vegas, Nevada January 4, 2015. The lock, which opens with a smart phone App and a touch, is smart enough to know what side of the door you are on and won't accidentally unlock the door when you are inside. A new subscription service offers unlimited e-keys and other benefits, a representative said. (Photo by Steve Marcus/Reuters)

(L-R) Michael Kasrpowicz, Jason Gillespie, Brett Lee and Glenn McGrath of Australia re-enact the famous Beatles album cover at Abbey Road on July 19, 2005 in London, United Kingdom (Photo by Hamish Blair/Getty Images)

Mr. Grindell Matthews with his latest invention, the new photographic gun which is the latest development in sky signs. 1933. It can throw a beam of light 15 miles into the sky. (Photo by Fox Photos)

A girl jumps over a campfire while celebrating Ivan Kupala Night, a traditional Slavic holiday not far from Kiev on July 6, 2013. During the celebration, originating in pagan times, people plait wreaths, jump over fires, and swim naked. (Photo by Sergei Supinsky/AFP Photo)

Thousands of species of amphibians are endangered and hundreds have already disappeared, but in recent years, a team of scientists and conservationists have re-discovered some of these “lost” species and uncovered previously unknown varieties. Here: Miniature glass frog. (Photo by Robin Moore)

Members of a teenage girl gang convincing an unwilling recruit to join the gang, circa 1955. (Photo by Vecchio/Three Lions)

Runner-up. “The heavens opened and the streets around Shibuya, Tokyo, were suddenly drenched in even more colour and movement. I was taking photos (my friend was holding the umbrella) when I noticed this woman at the crossing. I’m pleased with the futuristic feel of the image”. (Photo by Katherine Bridgestock/The Guardian)