A participant of the sled dogs race in action with the dogs in Stroehen (Lower Saxony), Germany, 18 October 2015. It is the first round of the North German Championship. (Photo by Peter Steffen/EPA)

An art installation formed with milk churns, made by land art artist Gerard Benoit a la Guillaume, is seen at the Chenau de Mayen in the resort of Leysin, Switzerland August 7, 2015. More than 80 milk churns were placed between the Tour d'Ai and the Tour de Mayen summits at an altitude of 2,000 meters (6,561 feet) above sea level under the direction of the artist, to be photographed for his ongoing art project entitled “Milk churns without borders”. (Photo by Denis Balibouse/Reuters)

“Dubai is sometimes called the “City of Gold” because of its stunning growth from a sleepy Gulf port to a world-famous business crossroads in the space of a single generation. Its nickname has a literal meaning for traders in the precious metal. The city is building itself up as a center for the gold trade, between sources in Africa and consumers in the rising economies of China and India”. – Kamran Jebreili via Associated Press

Photo: A gold press operator collects 10 gram gold blanks to press them with the logo of the Emirates Gold company in Dubai, United Arab Emirates. Gold prices remained relatively steady in 2012, close to $1,700 an ounce. (Photo by Kamran Jebreili/AP Photo)

“I have been photographing this group of urban foxes in Bristol for over 12 months; what started off as a chance encounter has become an obsession for me and has changed my feelings and attitudes towards urban foxes forever...”. – Ian Wade. (Photo by Ian Wade)

Long-tailed mayflies (Palingenia longicauda) at Tisza river near Tiszainoka 135km (84 miles) southeast of Budapest, June 23, 2013. Millions of these short-lived mayflies engage in a frantic rush to mate and reproduce before they perish in just a few hours during “Tiszaviragzas” or Tisza blooming season from late spring to early summer every year. (Photo by Laszlo Balogh/Reuters)

Maratus is a spider genus of the Salticidae family (jumping spiders). These spiders are commonly referred to as peacock spiders due to their colorful abdominal flaps that they display during courtship. In at least one species, Maratus vespertilio, the expansion of the flaps also occurs during ritualised contests between males. All described species, except M. furvus, are endemic to Australia. (Photo by Jurgen Otto)

A baby rhesus macaque (Macaca mulatta) looks up as it plays with a tiger cub at a zoo in Hefei, Anhui province, August 2, 2012. (Photo by Jianan Yu/Reuters)

A woman travels on a train stopping at a subway station visited by foreign reporters in central Pyongyang, North Korea on April 14, 2017. (Photo by Damir Sagolj/Reuters)