A member of the “Morenada Los Cocanis” group dances during the Carnival parade in Oruro February 14, 2015. Thousands of dancers and tourists attend the carnival celebrations in Oruro, south of La Paz. (Photo by David Mercado/Reuters)

A masked reveller poses near Saint Mark's Square during the Venetian Carnival in Venice January 31, 2015. (Photo by Stefano Rellandini/Reuters)

A trader weighs tobacco at a market in el-Fasher, in North Darfur February 5, 2015. Tobacco is one of the North Darfur war zone's main cash crops. (Photo by Mohamed Nureldin Abdallah/Reuters)

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)

Dancers perform during the annual Tbilisoba festival, celebrating Tbilisi City Day in Tbilisi, Georgia, October 17, 2015. Tbilisoba is an annual October festival, celebrating the diversity and history of Tbilisi, the capital of Georgia. (Photo by David Mdzinarishvili/Reuters)

A picture taken with slow shutter speed shows Emily Vaca performing in the finals of the Tenth World Salsa Festival in Cali, Colombia, 04 October 2015. (Photo by Christian Escobar Mora/EPA)

Fighters of the Popular Resistance Committees stand during a graduation ceremony of the affiliate special forces of the Popular Resistance, in Yemen's southwestern city of Taiz October 8, 2015. (Photo by Reuters/Stringer)

People in an illuminated cycle rickshaw look at a light installation at the Old Royal Library during the opening day of the "Festival of Light" show in Berlin, Germany, October 9, 2015. (Photo by Hannibal Hanschke/Reuters)