Merit Prize Winner: “A Well Earned Rest in the Sahara”. This photo of Moussa Macher, our Tuareg guide, was taken at the summit of Tin-Merzouga, the largest dune (or erg) in the Tadrat region of the Sahara desert in southern Algeria. Moussa rested while waiting for us to finish our 45-minute struggle to the top. It only took ten minutes of rolling, running, and jumping to get back down. The Tadrat is part of the Tassili N'Ajjer National Park World Heritage area, famous for its red sand and engravings and rock paintings of cattle, elephants, giraffes, and rhinos that lived there when the climate was milder. Photo location: Summit of Tin-Merzouga, Tadrat, Tassili N'Ajjer National Park, Algeria. (Photo and caption by Evan Cole/National Geographic Photo Contest)

Masked participants stand in St.Mark's Square during the Carnival on February 10, 2007 in Venice, Italy. (Photo by Marco Di Lauro). P.S. All pictures are presented in high resolution.

Two young boys kneel on stools on either side of a round table as one uses a match to this the other's cigarette, November 12, 1928. (Photo by FPG/Getty Images)

A frog appears to have a big smile for the camera, Russia. Things are heating up at the Comedy Wildlife Photography Awards as the shortlisted final 40 entries are revealed. This year's competition has featured over 2200 hilarious entries from around the world with photos including a fox face planting in the snow, a dancing brown bear and a pair of seemingly headless penguins – all beautifully photographed with perfect comedy timing and a strong conservation message. (Photo by Artyom Krivosheev/Barcroft Images/Comedy Wildlife Photography Awards 2016)

Catherine Hollis of Chester, Pa., and Izzy Weintraub of Atlantic City eat Cherrystone clams at Atlantic City's annual clam-eating contest September 16, 1946. They finished 96 and 66 clams respectively in 20 minutes. (Photo by Sam Myers/AP Photo)