A Hawaiian cleaner wrasse provides its cleaning services to a yellowfin goatfish in a reef community off the Big Island in Hawaii. Cleaner species help rid their hosts of ectoparasites, dead tissue, bacteria and fungi. Studies have shown cleaning to play a vital role in keeping many reef ecosystems healthy. (Photo by Marty Snyderman/Caters News Agency)

Japanese chorus girls appear to be drilling in military tactics atop their theater building as they perform salutes, June 30, 1937. The officer is from the Japanese regular army and says the girls display more rhythm in their drills than do the regular troops. (Photo by AP Photo)

Russian artist Maria Gazanova (L) works on her "The Alive Painting" art work during the Art Krasnoyarsk annual festival in Siberian city of Krasnoyarsk, Russia November 4, 2015. (Photo by Ilya Naymushin/Reuters)

A jockey falls off during a traditional Barapan Kebo or buffalo races, in Taliwang, on the island of Sumbawa, West Nusa Tenggara, Indonesia November 22, 2015. Around 250 pairs of water buffalo took part in the Barapan Kebo ahead of the planting season, for prizes which included a top prize of a pilgrimage to Mecca. (Photo by Sigit Pamungkas/Reuters)

A picture made available on 21 July 2016 shows a visitor having a meal from a toilet bowl at “Jamban Cafe” (lit. Toilet Cafe) in Semarang, Central Java, Indonesia, 16 July 2016. The cafe was created by a sanitation expert for education purposes to stress the importance of using a dedicated toilet and keeping it clean to prevent disease. (Photo by EPA/Purwanto)

Aegean airlines air hostesses take selfies after a news conference in Athens, Wednesday, March 28, 2018. In a deal worth up to $5 billion, Greek airline Aegean says it will buy 30 new Airbus aircraft, with the option of an additional 12, to upgrade its fleet as the country expects to break tourism records. The signing of the final purchase agreement is expected in June. (Photo by Petros Giannakouris/AP Photo)

A grey heron is seen at the Sempione park, after Lombardy was downgraded from a red to an orange zone, loosening the coronavirus disease (COVID-19) restrictions including allowing non-essential shops to re-open, in Milan, Italy, April 13, 2021. (Photo by Flavio Lo Scalzo/Reuters)

Syrian Internal Security Forces dance in celebration during their graduation ceremony, at Ain Issa desert base, in Raqqa province, northeast Syria, Thursday, July 20, 2017. Some 250 residents of Syria's Raqqa province are the latest batch to graduate from a brief U.S-training course that is preparing an internal security force to hold and secure areas as they are captured from Islamic State militants. (Photo by Hussein Malla/AP Photo)