Medic James E. Callahan of Pittsfield, Mass., gives mouth-to-mouth resuscitation to a dying soldier in war zone D, about 50 miles northeast of Saigon, June 17, 1967. Thirty-one men of the 1st Infantry Division were reported killed in the guerrilla ambush, with more than 100 wounded. (Photo by Henri Huet/AP Photo)

Joseph Ford is a 39-year-old photographer from Brighton, UK. He creates images seamlessly camouflaging people into backgrounds using knitwear made by Nina Dodd. It can take Dodd, 51, up to 40 hours to knit one item of clothing. This image of a man posing in knitwear, camouflaging into tiles of the steps and wall, is a personal favourite of Joseph’s. (Photo by Joseph Ford/South West News Service)

Women dancing at the disco club Xenon in New York City, USA in 1978. Xenon was a popular disco in Manhattan in the late 1970s and early 1980s. It was the only nightclub popular enough to compete with Studio 54. (Photo by Waring Abbott/Getty Images)

A racegoer flashes her undies in front of the racing crowd during Caulfield Cup Day at Caulfield Racecourse on October 21, 2017 in Melbourne, Australia. (Photo by Splash News and Pictures)

Villager search for a place for the roasted pigs in Dalem Temple at Timbrah Village on February 27, 2014 in Karangasem, Bali, Indonesia. Usaba Dalem is an annual ritual held by the people of Timbrah Village, during this ritual all the villagers will cook roasted pigs and carry them to Dalem Temple as an offering to God and an expression of gratitude for a successful harvest. (Photo by Putu Sayoga/Getty Images)

Snorkellers approach an adult manatee at Three Sisters Spring, Crystal River, Florida. You might imagine that coming face to face with one of these enormous underwater mammals would cause some concern. However, the likelihood is that the rotund creature just wants you to scratch its belly while it floats around happily, as world-renowned underwater photographer Alex Mustard discovered. (Photo by Alexander Mustard/Barcroft Media)

Sophie and Sarah, old English sheepdogs, watch the sea from their plastic chairs. Amateur photographer Cees Bol, from the Netherlands, documents the lives of his beloved pooches Sophie and Sarah by taking pictures of them every day. (Photo by Cees Bol/Caters News Agency/Mercury Press)