A line of soldiers firing handguns during a training session, circa 1920. (Photo by Keystone). P.S. All pictures are presented in high resolution.

Glamorous strongwoman Joan Rhodes exercises her strength whilst tackling housework in her flat in Hampstead, north London, March 1958. (Photo by Ken Harding/BIPs). P.S. All pictures are presented in high resolution.

A man from the Dani tribe cuts the head of a pig after cooked by traditional way which is use burned hot stones at Obia Village on August 9, 2014 in Wamena, Papua, Indonesia. The stone-age Dani tribe live a traditional existence in the Baliem Valley, which is situated 1600 metres above sea level in the heart of the Cyclops Mountains. (Photo by Agung Parameswara/Getty Images)

The sun rises over the north sea as The Couple by artist Sean Henery sits just of the coast at Newbiggin-by-the-Sea, England, Wednesday October 8, 2014. (Photo by Owen Humphreys/AP Photo/PA Wire)

Christian pilgrims from Brazil embrace after they are baptized in the water of the Jordan River during a ceremony at the Yardenit baptismal site near the northern Israeli city of Tiberias October 15, 2014. (Photo by Finbarr O'Reilly/Reuters)

The annual Sculpture by the Sea exhibition in Sydney features dozens of sculptures on Bondi and Tamarama beaches and along the coastal path between them. The free outdoor exhibition, now in its 18th year, stretches for 2km along the coastline and includes work by artists from 16 countries. It runs from 23 October to 9 November 2014. Here: “Breaching” by Michael Greve is displayed during the 2014 Sculptures by the Sea exhibition at Marks Park on October 23, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Participants dressed in Heroic Fantasy costumes pose for a picture as they wait backstage during the first edition of the HeroFestival in Marseille, November 9, 2014. The festival is dedicated to American superhero comics, Japanese mangas, Heroic Fantasy characters and video games universes. (Photo by Jean-Paul Pelissier/Reuters)

Galapagos – Rocking the Cradle: Four major ocean currents converge along the Galapagos archipelago, creating the conditions for an extraordinary diversity of animal life, April 25, 2016. The islands are home to at least 7,000 flora and fauna species, of which 97 percent of the reptiles, 80 percent of the land birds, 50 percent of the insects and 30 percent of the plants are endemic. (Photo by Thomas P. Peschak for National Geographic/World Press Photo)