Two male African mantis Pseudempusa pinnapavonis (Peacock Mantis) show their colours in Igor's home studio in Munich, Germany. (Photo by Igor Siwanowicz/Barcroft Media)

An alligator is pictured stuck in the mud of the dry Pilcomayo river, which is facing its worst drought in almost two decades, on the border between Paraguay and Argentina, in Boqueron, July 3, 2016. (Photo by Jorge Adorno/Reuters)

In this May 17, 2015, photo, two men walk past pagodas at Ngwe Saung beach, Pathein township, about 145 miles from Yangon, Myanmar. (Photo by Khin Maung Win/AP Photo)

Two and a half year-old Jennifer Martin in tears during a visit to Santa at Harrods department store in London, 10th December 1949. (Photo by William Vanderson/Fox Photos/Hulton Archive/Getty Images)

Two students in Birmingham, United Kingdom dressed as policewomen enjoy a takeaway on October 31, 2018. Halloween party-goers enjoyed one hell of a night for the annual fright-fest. (Photo by Caters News Agency)

A two-horse team street cleaner, with sprayer, squeegee, and roller at rear. New York, between ca. 1910 and ca. 1915. (Photo by NYC Municipal Archives)

Members of the Raskol gang “Dirty Dons 585”, 9 Mile Settlement, Port Moresby. All of these young men committed a set of rapes and armed robberies. The gang members admit that two thirds of their victims are women. (Photo by Vlad Sokhin)