The CBRE Urban Photographer of the Year competition – now in its ninth year – encourages professional and amateur photographers to capture cities at work. Here: Dog Walker – 15:00. The competition allows photographers to enter up to 24 images, one representing each hour of the day. (Photo by Johanna Siegmann)

“The Skeleton Krewe was founded in 1999 by Christopher Kirsch. Inspired by the early days of Carnival before tractors and floats replaced walking processions, the Krewe has become one of New Orleans' premier marching clubs. The Krewe began actively marching as a small group of friends, but has grown to 40 active members”. – The Skeleton Krewe. Photo: “The Skeleton Krewe 2013 – Manning”. (Photo by Kevin O'Mara)

Mr. Zhong Hua, of Johns Hopkins University School of Medicine, took this image of the peripheral nerves (those outside of the brain) in an 11.5-day-old mouse embryo, magnified five times. (Photo by Zhong Hua)

A visitor passes behind the sculpture “Puma-Dentist” made with plastic, wax and original heads of a puma and a hind by Austrian artist Deborah Sengl during an exhibition at the art gallery Deschler in Berlin April 15, 2008. (Photo by Fabrizio Bensch/Reuters)

Mounted cop in action on Tremont Street in Boston, Massachusetts, 1920 – 1929 (approximate). (Photo by Leslie Jones)

Clouds float over an open field January 3, 2007 in Shirley Heights, Antigua. (Photo by Joe Raedle/Getty Images)

A selection of winning images from the Life in Another Light photo contest 2020, from Kolari Vision. Here: Lights and Shadows in the Dolomites, in the landscape infrared category. (Photo by Tomasz Grzyb/Kolari Vision)