German flying ace Baron Manfred von Richthofen (1892–1918) also known as The Red Baron with his dog Moritz, circa 1916.

An alert-looking Maine Coon during the Grand Prix Royal Canin cat exhibition in Moscow, Russia on December 4, 2016. The breed’s origin is unknown, but one legend claims it is descended from cats brought to the US by an English seafarer called Captain Coon. (Photo by Dmitry Serebryakov/TASS)

Beneath the Swedish capital lies an intricate web of underground train lines. More than 90 of the 100 stations in the 110km tunnel system, sometimes referred to as “the world’s longest art gallery”, have been decorated with paintings, installations, mosaics and sculptures by 150 artists since the 1950s. After spending a couple of weeks exploring arctic Norway and Sweden, London-based travel photographer Conor MacNeill headed underground to capture images of the metro stations. Here: A rainbow arcs over a girl on the platform of Stadion station. (Photo by Conor MacNeill/The Observer)

An elephant decorated with a cloth walk in the annual Perahera (street pageant) at Rajamaha viharaya Buddhist temple in Colombo, Sri Lanka September 10, 2016. (Photo by Dinuka Liyanawatte/Reuters)

Participants of the Sarenza High Heel Race 2015 warm up prior to the race during a party of the online shoe store, in Paris, Thursday, October 15, 2015. Competitors in teams of three girls race wearing shoes with more than 8 cm-high heels. (Photo by Francois Mori/AP Photo)

An employee of German car manufacturer Mercedes Benz adjusts the brand's characteristic star on a GLA model at their production line at the factory in Rastatt, Germany, January 22, 2016. (Photo by Kai Pfaffenbach/Reuters)

A Green Crowned Brilliant is pictured at a Hummingbird feeding station on January 15, 2016 in Alajuela Costa Rica. Of the 338 known species of Hummingbird worldwide there are around 50 in Costa Rica. Hummingbirds are named for the distinctive sound made by their tiny beating wings, and are admired for their vibrantly coloured iridescent plumage. Their ability to hover, with wings beating between 12 and 90 times a second, and to fly backwards makes them different from all other birds. (Photo by Dan Kitwood/Getty Images)

These stunning images document the everyday lives of the men, women and children of the Mentawai tribe. The Mentawai people, a native population in Indonesia, are famous for their decorative tattoos and for living a semi-nomadic life on the Mentawai Islands in West Sumatra. Shot by professional photographer Mohammed Saleh Bin Dollah, the series captures a glimpse of life on the island as the Mentawai men smoke and hunt for food and the children play in the river. Here: A young boy helps a woman to prepare food taken on July 19, 2014 on the Mentawai Islands, Indonesia. (Photo by Muhamad Saleh Dollah/Barcroft Media)